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97L growing more organized, will bring heavy rain to the Lesser Antilles

By: Dr. Jeff Masters, 3:55 PM GMT on July 19, 2009

The tropical wave near 12N 52W, about 600 miles east of the Lesser Antilles Islands (97 L), has grown more organized this morning as it tracks west at about 20 mph. This wave is surrounded by an area of very dry air from the Sahara Desert, but 97L has been able to steadily moisten a large region of the atmosphere over the past day, insulating itself from the dry air. This moistening process has been aided by sea surface temperatures (SSTs) that have steadily increased from 26.5°C to 27.5°C, plus the presence of only 10 knots of wind shear. The system now has a small area of intense thunderstorms near its center, with some rotation of the cloud pattern evident at mid-levels of the atmosphere. An upper-level outflow channel has opened to the north, and there is evidence that surface spiral bands are beginning to form. This morning's QuikSCAT pass missed 97L, so we don't know what is happening at the surface.

Wind shear is a modest 10 knots over the disturbance, and is forecast to remain in the moderate 10 - 15 knot range through Monday morning. This should allow further development to occur today, and 97L could be approaching tropical depression strength on Monday as it moves through the central Lesser Antilles Islands. Monday night, shear is expected to rise to 20 - 30 knots, thanks to the presence of a trough of low pressure at upper levels of the atmosphere over the eastern Caribbean. Since 97L is a relatively small system, it is very vulnerable to wind shear. This shear may be able to drive some of the dry air west of 97L deep into its interior, significantly disrupting the disturbance. Shear will remain high along 97L's path through Thursday, when the storm should be in the western Caribbean near Cuba. If there is anything left of 97L by then, some development is possible. The National Hurricane Center gave 97L a low (less than 30% chance) of developing into a tropical depression in the next 48 hours in their 8am Tropical Weather Outlook. However, I'd say the odds are now in the medium range (30 - 50%).

None of the computer models are forecasting tropical storm development over the next seven days.


Figure 1. Current satellite image of African wave 97L.

I'll have an update Monday morning. As 97L approaches the islands, you may want to follow local observations there using our wundermap for 97L.

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

17 mins till CIMSS update

LOL any one home

Quoting Tazmanian:

LOL any one home


Lol. I'm waiting until CIMSS
burned after posting, u must have missed my wonderful description about how all that is a haircut!! The heart is farther south. That is what i meant where convection was blowing up. u see i dont know jack about how a hurricane developes, but i do see how 97 invest is rolling like a bowling ball towards the carrib, and its going to take more than a puff of wind to blow it out!!! LOL
say good bye too 97L all it was a good little fighter but has you can see wind shear has rip it a part
Quoting Tazmanian:
say good bye too 97L all it was a good little fighter but has you can see wind shear has rip it a part


You have said that each of the last 3 nights too and well its still around
Taz ripped apart now?
this time its rip up for good by the wind shear
Quoting moonlightcowboy:
History Channel "That's Impossible" - Tuesday at 9:00 pm cst.

Episode - "Weather Warfare"

The power to use tornados, hurricanes and the deadliest weather as weapons of war may now be possible. We'll investigate reports that weather weapons are in development and reveal the technology that--in the future--could turn hurricanes, earthquakes, even tsunamis into some of the most powerful and plausibly deniable weapons of mass destruction the world has ever seen.


Sigh. :( Why don't they use all that intellect and power and money for peace. Add plausible deniability and whoever uses it can never be blamed. Sorry. Just caught my eye. Back to Mother Nature's weather. Is this shear the end of the little storm that could?
Taz have u been hittin the sauce, it isnt dead.
Even though wind shear has now begun to clearly impact the system, I'm not going to count it out. Been a fighter all throughout its lifetime, so I can't underestimate it. Just going to sit back and watch...starting tomorrow AM. Have a good night y'all and be civil.
whats take this time too say a few words too are be loveing dead 97L it put up a good fight and the wind shear has won the fight
Quoting Tazmanian:
whats take this time too say a few words too are be loveing dead 97L it put up a good fight and the wind shear has won the fight


you tend to write things off before they are actually gone, seems you do it a lot as well
New Map
taz your trying to rile up these 97ivest lovers? arent u lol
The vorticity continues to get stronger-
remember it tricked us that we thought it would be dead and then this am it surpised us and taz should of look but wasn't able to get on here
Quoting BurnedAfterPosting:


you tend to write things off before they are actually gone, seems you do it a lot as well



you no am this massing with evere one


LOL
2020. Patrap
97 just got wacked upside its lil head..LOL




Floater - RGB Color Infrared Loop
2021. ackee
this hurricane seasons shear rule Iam thinking we have less than ten name storms this seasons
why do we love hurricanes?
Quoting Tazmanian:
this time its rip up for good by the wind shear


You said that not to long ago..
2024. Patrap
On a serious note,..one has to wary of any intact CV circulation,..as 1995 and 2008 showed us,certain CV waves are tenacious and can survive the Trek to a more Favorable environment.

Jeff Masters will be the first to convey that lil bit o wisdom.

Never discount a CV circ till its inland or dissipated.

Nighty.

Dont try to act like you just dont love em!!! lol
Quoting Patrap:
On a serious note,..one has to wary of any intact CV circulation,..as 1995 and 2008 showed us,certain CV waves are tenacious and can survive the Trek to a more Favorable environment.

Jeff Masters will be the first to convey that lil bit o wisdom.

Never discount a CV circ till its inland or dissipated.

Nighty.



Well said
Quoting cchsweatherman:


I understand since they are the real experts and the people in charge. What my purpose is when creating those graphics and explanations is to try and offer people an easier perspective as to whats going on and try my best to provide easy-to-understand explanations since I know that some people who access this site don't have a deep meteorological background. In no way and shape do I intend to overrule the government-run agencies like the NHC and NWS.


Don't worry about it CCHS, you were asked by several of us to do this type of graphic last year, and we find it very helpful.

The information on this blog is the opinion of those who write it, and does not have to be only what nhc, etc say. That's why its a blog.

Quoting ackee:
this hurricane seasons shear rule Iam thinking we have less than ten name storms this seasons



i think will see less then 5 too 7 name storms that is if we can get there
It's still firing up convection:
View Comments (2008)

lool irony. anyway i dont think 97l will be athreat unless it somehow survives into the gulf. which it wont. this season is a bust. NEXT
Quoting Tazmanian:



i think will see less then 5 too 7 name storms that is if we can get there


It is only July 19th and El Nino is still not projected to be very strong

I think we will get closer to 10-12 named storms; in the heart of the season we can rattle off 4 or 5 storms in a short amount of time. Based on what we have seen mostly favorable conditions will exist in August.
Quoting winter123:
View Comments (2008)

lool irony. anyway i dont think 97l will be athreat unless it somehow survives into the gulf. which it wont. this season is a bust. NEXT


you are a bust; POOF!! lol
that anticyclone over Panama has expanded
will take one name storm at a time and see how many we get at the end
Quoting BurnedAfterPosting:
that anticyclone over Panama has expanded

Could you post a map. I'd like to see.
Quoting weatherwatcher12:

Could you post a map. I'd like to see.


nevermind that isnt an anticylcone I dont think lol
Quoting BurnedAfterPosting:


nevermind that isnt an anticylcone I dont think lol

lol
I see one forming in the Bahamas though
Quoting winter123:
View Comments (2008)

lool irony. anyway i dont think 97l will be athreat unless it somehow survives into the gulf. which it wont. this season is a bust. NEXT

wt i thought u said this a gonna be when it came off africa
Just checking back in and it looks like 97L's central convection is getting sheared pretty nicely.
Quoting Stormchaser2007:
Just checking back in and it looks like 97L's central convection is getting sheared pretty nicely.


yea but it has maintained its structure nicely so far, I even think the circulation has become even more defined despite the shear.
Quoting Stormchaser2007:
Just checking back in and it looks like 97L's central convection is getting sheared pretty nicely.



yup
Quoting BurnedAfterPosting:
I see one forming in the Bahamas though

I think that black spot clearing out in the central Caribbean could be a developing anticyclone
Quoting Stormchaser2007:
Just checking back in and it looks like 97L's central convection is getting sheared pretty nicely.

sure is lol
Quoting BurnedAfterPosting:


yea but it has maintained its structure nicely so far, I even think the circulation has become even more defined despite the shear.

The 850mb vorticity has increased
Quoting winter123:
View Comments (2008)

lool irony. anyway i dont think 97l will be athreat unless it somehow survives into the gulf. which it wont. this season is a bust. NEXT


-facepalm- 2004.. 2004..2004..2004..2004..2004..El Nino..Cold Fronts.. pat, I need some 70's or 80's music that would be proper for this.
well I am going to bed, neat thing for me is that my cellphone rocks so much I can check the 2am TWO on it and not have to be on here to do so

I did that last night too lol

see you all tomorrow, when many tropical weather lovers will run to their computers in the morning to see what has become of 97L, I compare it to a kid coming down the stairs on Christmas morning to see what presents are under the tree LOL
That convection won't give up. It just keeps re-firing
97l, new wave?, carlos reforming?? New blog entry, now i'm going to bed. :)

http://www.wunderground.com/blog/winter123/show.html
Looks like it's trying to rally against the shear and get that convection together.
New model runs are out for 0z
Quoting BurnedAfterPosting:


nevermind that isnt an anticylcone I dont think lol


It sure is, this is the one I've been mentioning.. see the anticyclonic turning? It's an Anticyclone.

http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8shr.html
2054. islagal
is the blob behind 97L looking a little interesting?
Quoting islagal:
is the blob behind 97L looking a little interesting?

Yeah. It's in the ITCZ, but if it can escape it could get interesting
Quoting reedzone:


It sure is, this is the one I've been mentioning.. see the anticyclonic turning? It's an Anticyclone.

http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8shr.html

On the satellite I'm seeing something that looks life a subtropical ridge. I could be wrong though.
Reed if I read that right. This lil storm is under 30kts of shear. And its still firing up convection. With that and the increased vorticity it sure is trying hard to hang on. I don't know what the shear is coming from. Or if it will get worse but is it ever going to get into a favorale environment? I think if it makes it to a good environment it will rapidly intensify. I know it's July. But this storm has been tenacious.
Quoting homelesswanderer:
Reed if I read that right. This lil storm is under 30kts of shear. And its still firing up convection. With that and the increased vorticity it sure is trying hard to hang on. I don't know what the shear is coming from. Or if it will get worse but is it ever going to get into a favorale environment? I think if it makes it to a good environment it will rapidly intensify. I know it's July. But this storm has been tenacious.

Shear is predicted to lift in 2-3 days. Maybe even less.
NHC taking a long time to update
If that Anticyclone strengthens, shear should lessen more quicker then the forecast. One model shows shear subsiding and moving northwest by tomorrow, Can't count on that model run though.
Quoting weatherwatcher12:
NHC taking a long time to update


Yeah. I'm wondering if they'll deactivate it again.
Good Morning everyone......Looks like 97L is getting hit with the higher shear i thought it would....
Quoting reedzone:
If that Anticyclone strengthens, shear should lessen more quicker then the forecast. One model shows shear subsiding and moving northwest by tomorrow, Can't count on that model run though.

I think it was the NOGAPS
Quoting homelesswanderer:


Yeah. I'm wondering if they'll deactivate it again.

Unlikely. The 850mb vorticity continues to increase. The convection may be gone but the circulation is still there.
97L is currently under 25kts of shear.
The blob at 5N 30W is the one to watch...as the Azore and Beremuda High strengthens and Shear subsides this week.....Ana will be coming from this blob!
Quoting BenBIogger:
97L is currently under 25kts of shear.

Don't write it off. Remember if the circulation survives the axis will move west and meet up with the anti cyclone
000
ABNT20 KNHC 200546
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT MON JUL 20 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND SHOWERS ASSOCIATED WITH A TROPICAL WAVE LOCATED A
COUPLE HUNDRED MILES EAST OF THE WINDWARD ISLANDS HAVE BECOME LESS
ORGANIZED OVER THE PAST SEVERAL HOURS. UPPER-LEVEL WINDS ARE
EXPECTED TO BECOME LESS FAVORABLE FOR THE DEVELOPMENT OF THIS
SYSTEM OVER THE NEXT 24 TO 48 HOURS. REGARDLESS OF DEVELOPMENT...
LOCALLY HEAVY RAINFALL AND GUSTY WINDS COULD AFFECT THE WINDWARD
ISLANDS DURING THE NEXT DAY OR SO AS THE WAVE MOVES WESTWARD AT 15
TO 20 MPH. THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS
SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER PASCH

Quoting weatherwatcher12:

Unlikely. The 850mb vorticity continues to increase. The convection may be gone but the circulation is still there.


Yeah. Looks pretty good on the RGB. And it kinda looks like its starting to go a little more northerly. or that could be because of the convection flaring up.
Wow, 97L is ragged.
Quoting TampaSpin:
Good Morning everyone......Looks like 97L is getting hit with the higher shear i thought it would....


Both of us knew it was going to hit the brick wall of shear.
And theres my answer. Lol.
Quoting BenBIogger:


Both of us knew it was going to hit the brick wall of shear.


There was believers and wishcasters.........LOL
Quoting weatherwatcher12:

Don't write it off. Remember if the circulation survives the axis will move west and meet up with the anti cyclone


I ain't writing it off. still has a slim chance imo
I have to say that the wave at the bottom right is looking good
Good night y'all. We'll see if it survives the night.
Quoting TampaSpin:


There was believers and wishcasters.........LOL


lol
I would not write if off either.....it still has a nice circulation intake but, in 6-12hrs the naked spin will wind down also....
Quoting weatherwatcher12:
I have to say that the wave at the bottom right is looking good


Just some itcz flare ups.
Quoting TampaSpin:
Good Morning everyone......Looks like 97L is getting hit with the higher shear i thought it would....

yeah a couuple days late lol
Shear is actually closer to 30-35kts imo....maybe even higher...
Quoting TampaSpin:


There was believers and wishcasters.........LOL


It's still got great shape considering the shear... D-max is approaching and convection is building once again. Just imagine if this thing had no shear to deal with:. We would have a problem
Quoting Funkadelic:


It's still got great shape considering the shear... D-max is approaching and convection is building once again. Just imagine if this thing had no shear to deal with:. We would have a problem


agree
Quoting btwntx08:

yeah a couuple days late lol


Your so wrong......go back and look at my quotes...i said it was under 10-15kts of shear..even last nite and it would increase....today and tonite....ROFLMAO.....Wishcaster!
don't quote ben blogger just ingore him i did a long way back imo
Quoting Funkadelic:


It's still got great shape considering the shear... D-max is approaching and convection is building once again. Just imagine if this thing had no shear to deal with:. We would have a problem


I strongly agree with you....if the Shear would not have been present 2 days ago along with the dry conditions and cooler waters...we could have had Ana already present.
Quoting btwntx08:
don't quote ben blogger just ingore him i did a long way back imo


Many probably did the same to you!
rightnow its in 20-25 kts of shear may go a bit higher to 30 but should lessen in a few days
Quoting TampaSpin:


Your so wrong......go back and look at my quotes...i said it was under 10-15kts of shear..even last nite and it would increase....today and tonite....ROFLMAO.....Wishcaster!

what the i was not wishcasting and yes i saw the quotes....and i barely came on and didn't it till now! lol
btw that wave at 5n 30w is still in the itcz it needs to break away from that then its something to watch but not right now
Quoting btwntx08:

what the i was not wishcasting and yes i saw the quotes....and i barely came on and didn't it till now! lol


Ok....whatever along with your buddies.....its all good!
Quoting btwntx08:
btw that wave at 5n 30w is still in the itcz it needs to break away from that then its something to watch but not right now


And yes i think i know that....hahaha
Definitely ragged, but definitely still some mid-level rotation and convective bursts. 97L is trying to hang despite the shear - heckuva fighter.
Quoting TampaSpin:


Ok....whatever along with your buddies.....its all good!

but now i agree with u on the near 30 kts shear on 97L and it is still to watch after it gets though the shear so its just wait and see game for a couple of days
Convection looks like it's trying to merge
Just looked at Data.....97L is vertually dead....it will be poof in 12hrs.....Shear will be ripping it apart!
this soon to be storm doesnt care about shear.
Quoting TampaSpin:
Just looked at Data.....97L is vertually dead....it will be poof in 12hrs.....Shear will be ripping it apart!

Look at the vorticity. Increasing every 3 hours. The pressure has dropped 3 millibars in the past 24 hours
97L is finally showing some lower level convergence as well.
Quoting TampaSpin:


Many
probably did the same to you!


Wow Tampa, serious whats your problem this year? Calling wishcasters, insulting people, ect. You weren't anything like that last year.
Quoting btwntx08:

but now i agree with u on the near 30 kts shear on 97L and it is still to watch after it gets though the shear so its just wait and see game for a couple of days


Honestly the shear was 15kts the other nite.....out of the NW.....if you would have zoomed in you could see the cloud tops blowing off.......5kts of shear does not cause that.....Yes it still bears some watching but, not much....LOOK East and watch the GOM and off the Atlantic seaboard the next few days.
Quoting TampaSpin:
Just looked at Data.....97L is vertually dead....it will be poof in 12hrs.....Shear will be ripping it apart!


You said the same thing last night.
I'm sorry to rain on some people's parade. But 97L is about to head into 40 Knots of Vertical Wind Shear. You can already see the shear's effect on satellite. Also, to the people denying Tampaspin you shouldn't be, He has been right all along with 97L. So quit saying he is wrong and wishcasting because you are only putting whatever you think your reputation is here in jeopardy.

Some of y'all need to relax and look at a WV Loop and have fun on here and learn. That's what needs to happen here. But I can't force some of you to do it.

Wxman504
weatherwatcher12
hmmm i see what u mean intersting
Quoting moonlightcowboy:
97L is finally showing some lower level convergence as well.

very true
SOI still positive

The divergence is also increasing
Quoting TampaSpin:
Just looked at Data.....97L is vertually dead....it will be poof in 12hrs.....Shear will be ripping it apart!


You do have to admit pressure is falling and getting convection again... Maybe 97l won't be destroyed after all
It can still make it, TS - maybe not tomorrow, but maybe past the islands if it can keep some circulation intact...it's doing that so far. With some low level convergence it may be able to keep creating some good lift through dmax to maintain its spin and convection, despite the shear blowing tops off. There is no shear with 97L at the mid-levels. Additionally, the anti-cyclone is growing off the northern SA coast into the Caribbean.
Convection is converging and exploding. It's defying the shear, but for how long.
Quoting CybrTeddy:


Wow Tampa, serious whats your problem this year? Calling wishcasters, insulting people, ect. You weren't anything like that last year.


Cybr know you for a long time......if i came across that to everyone i apologize...it was only intended to just a hand full..
Quoting moonlightcowboy:
It can still make it, TS - maybe not tomorrow, but maybe past the islands if it can keep some circulation intact...it's doing that so far. With some low level convergence it may be able to keep creating some good lift through dmax to maintain its spin and convection, despite the shear blowing tops off. There is no shear with 97L at the mid-levels. Additionally, the anti-cyclone is growing off the northern SA coast into the Caribbean.


agree
2113. Relix
97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?
Quoting TampaSpin:


Honestly the shear was 15kts the other nite.....out of the NW.....if you would have zoomed in you could see the cloud tops blowing off.......5kts of shear does not cause that.....Yes it still bears some watching but, not much....LOOK East and watch the GOM and off the Atlantic seaboard the next few days.

yup will just need to watch and see how it plays out
Pressure (MSLP): 1011 mb (29.85 inHg | 1011 hPa)
Sustained wind speed (1 min. avg.): 25 knots (29 mph | 13 m/s)
Quoting Relix:
97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?

It could be the convection expanding
Quoting Relix:
97L is like the brave little toaster!! Haha, holding out against shear. Is it me or is there more of a noticeable WNW component right now, or is it the mess of convection messing with my eyes?

I think it's an illusion from the upper level shear blowing the tops off 97L. I believe it's still holding basically true to the westerly steering patterns. And, unless mine are deceiving me, there may actually be a small swesterly movement.
Quoting Funkadelic:


You do have to admit pressure is falling and getting convection again... Maybe 97l won't be destroyed after all


10% chance maybe....I don't see it making it.
Pressure dropping at a buoy just east of the invest:
Wind Direction (WDIR): E ( 80 deg true )
5-day plot - Wind Speed Wind Speed (WSPD): 19.4 kts
5-day plot - Wind Gust Wind Gust (GST): 23.3 kts
5-day plot - Wave Height Wave Height (WVHT): 9.2 ft
5-day plot - Dominant Wave Period Dominant Wave Period (DPD): 8 sec
5-day plot - Average Period Average Period (APD): 5.8 sec
5-day plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.91 in
5-day plot - Pressure Tendency Pressure Tendency (PTDY): -0.05 in ( Falling )
5-day plot - Air Temperature Air Temperature (ATMP): 81.3 °F
5-day plot - Water Temperature Water Temperature (WTMP): 81.9 °F
5-day plot - Dew Point Dew Point (DEWP): 76.8 °F
5-day plot - Heat Index Heat Index (HEAT): 88.5 °F
Buoy to the west also reporting falling pressure:
Wind Direction (WDIR): E ( 80 deg true )
24-hour plot - Wind Speed Wind Speed (WSPD): 22.0 kts
24-hour plot - Wave Height Wave Height (WVHT): 7.2 ft
24-hour plot - Dominant Wave Period Dominant Wave Period (DPD): 8 sec
24-hour plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.90 in
24-hour plot - Pressure Tendency Pressure Tendency (PTDY): -0.05 in ( Falling )
24-hour plot - Air Temperature Air Temperature (ATMP): 81.7 F
24-hour plot - Water Temperature Water Temperature (WTMP): 81.5 F
24-hour plot - Dew Point Dew Point (DEWP): 75.7 F
24-hour plot - Heat Index Heat Index (HEAT): 88.5 F
the shear doesnt look as bad
The ULL to the North is causing alot of the Shear.....it too is moving nearly due West and might start moving more WSW......Shear won't be relaxing anytime in the next couple of days.
Quoting TampaSpin:


Cybr know you for a long time......if i came across that to everyone i apologize...it was only intended to just a hand full..


I know man, its not your forecasting though thats off (pretty darn accurate) its the little end comments that tend to well.. rall up the blog.
Couldnt sleep and finished my book. :( The CMC takes this smack into central Louisiana. Yea I know, I know. IF it survives, too early, etc. Just found that a little too close for comfort.
Looks to be trying to fire some heavy convection
Approaching Dmax.
The other little guy at 30W flaring up pretty good too.
Quoting homelesswanderer:
The other little guy at 30W flaring up pretty good too.
Quoting FloridaTigers:
Approaching Dmax.

Yes to both of these
Has some SAL to get through
looks to me like a big part of the convection flare up is more from DMAX and divergence created by the ULL that anything else.
Quoting SouthALWX:
looks to me like a big part of the convection flare up is more from DMAX and divergence created by the ULL that anything else.

That's the whole point of DMAX. To flare up and there is also improved convergence. It's taking advantage of DMAX.
Quoting weatherwatcher12:

That's the whole point of DMAX. To flare up and there is also improved convergence


The flare up is from the ULL causing uplift...
Yeah it does have to get through the SAL. I don't know if either of these will survive. But if this is any indication of what the actual CV season will be like I think it may be a lot busier than people think. This is my first season tracking the storms. But the SOI looks like its not doing what was expected of it either.
Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob .I think it was over haiti for a few days you guys may remember I don't remember who but there was a detailed explanation concerning the divergent factors given that I found to be spot on.. Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.
Agree with TS on this, though dmax will play a role, this is a case of divergence.
Quoting SouthALWX:
Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob ... Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.


Dido.....well said!
Quoting SouthALWX:
Have to disagree, convergence may be increasing but if you look at the divergent upper air pattern it's clear to see the culprit is the ULL. Reminds of a month or so ago when divergent upper flow created a "blob" that was talked about on here for two nights ... Once the divergence shut down so did the blob ... Nothing to really look at now imo until a few days out when 97 emerges (if) in the western to central carribean.

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.
Quoting weatherwatcher12:

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.

So if it can detach itself from the divergence and fire it's own convection it has a fair chance.
Quoting weatherwatcher12:

Even if the convection is just ULL there is still a high 850mb vorticity associated with it.


correct, and that vorticity is what will be watched in the carribean should it be maintained to any extent.
I think I see what could be an anti-cyclone forming in the central Caribbean
a key here is to follow the shape of convection .. it's following the divergence as it fans out forming a left facing "V" shape.
India Meteorological Department
Tropical Cyclone Bulletin Number ONE
DEPRESSION BOB03-2009
8:30 AM IST July 20 2009
=====================================

Sub: Depression over northwest Bay of Bengal

At 3:00 AM UTC, Latest satellite imageries and coastal observation indicate that a depression has formed over northwest Bay of Bengal and lays centered near 21.0N 88.5E or about 120 kms southeast of Digha, 160 kms east-southeast of Balasore, and 200 kms southwest of Khepupara.

Satellite imagery indicates gradual organization of convection during past 12 hours. The Dvorak intensity of the system is T1.5. Associated broken intense to very intense convection lies over Bay of Bengal between 18.5N and 21.5N and to the west of 89.5E. The lowest cloud top temperature due to convection is around -70C.

Maximum 3 minute sustained winds near the center is 25 knots with a central pressure of 992 hPa. The state of the sea is rough to very rough around the system's center.

Vertical wind shear of horizontal wind over the region is low to moderate (around 10-20 knots). Sea surface temperature is about 29C. The system is supported by upper level divergence and lower level convergence. Strong east-southeasterly winds prevail over the region in the upper tropospheric level. As observed at 3:00am UTC, the 24 hours pressure fall is higher in the west-northwesterly direction and is maximum (-3.6 hPa) over Digha.

Considering all the above, the system is likely to intensify further and move in a west-northwesterly direction and cross north Orissa-West Bengal coast between Balasore and Digha around 1200 PM UTC.
well im out guys, we'll know more of 97s future very soon no reason to jump to RIP/apoco-cane yet =] Vorticity is consolidated and I've seen waves survive worse so we'll see. Of course I've seen waves die in what seemed perfect conditions too. It remains to be seen, what we do know is that the convection tonight is of little consequence to 97's future. I could be wrong, but that's my take =]
New shear map. Any thoughts.
Another view. On this it doesn't appear to be pulling to the north.

Link
Quoting weatherwatcher12:
New shear map. Any thoughts.


NO surprises.....you can see the shear increasing the past 24hours.....i won't change too much the next 24 either.
Look the divergence flow has been cut off from the ULL
The convergence has increased too
Quoting weatherwatcher12:
The convergence has increased too


The increase in convergence is likely diurnal.
Quoting TheWeatherMan504:


The increase in convergence is likely diurnal.

Probably, but last time we had none so it must be improving
We got a buoy dropping like a rock just wnw of our invest:
Wind Direction (WDIR): ENE ( 70 deg true )
24-hour plot - Wind Speed Wind Speed (WSPD): 22.9 kts
24-hour plot - Wave Height Wave Height (WVHT): 7.9 ft
24-hour plot - Dominant Wave Period Dominant Wave Period (DPD): 8 sec
24-hour plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.88 in
24-hour plot - Pressure Tendency Pressure Tendency (PTDY): -0.04 in ( Falling )
24-hour plot - Air Temperature Air Temperature (ATMP): 80.8 F
24-hour plot - Water Temperature Water Temperature (WTMP): 81.1 F
24-hour plot - Dew Point Dew Point (DEWP): 75.7 F
24-hour plot - Heat Index Heat Index (HEAT): 86.7 F
A ship just reported a pressure of 1010 millibars near the invest
its pouring at the house
Quoting TampaSpin:
its pouring at the house

That was a pretty big shower
Approaching DMAX
Sheap Lol. I mean shear. Comparisons. Depending on which you choose. It may get better or worse. Lol. Didn't realize they were so different.

http://www.meteo.psu.edu/~gadomski/COMPSHEARATL_0z/comploop.html

That wind/pressure chart sre shows that pressure tanking. Kinda hard to deny that.
Quoting homelesswanderer:
Sheap Comparisons. Depending on which you choose. It may get better or worse. Lol. Didn't realize they were so different.

http://www.meteo.psu.edu/~gadomski/COMPSHEARATL_0z/comploop.html

That wind/pressure chart sre shows that pressure tanking. Kinda hard to deny that.

Yeah, and so does that ship report
Quoting weatherwatcher12:

Yeah, and so does that ship report


yep.
Good night. We will see what is happening with our invest in the morning.
Quoting weatherwatcher12:
Approaching DMAX


What is DMAX?
Quoting natrwalkn:


What is DMAX?

When cloud tops cool and convection explodes. Strongest just before suunrise
Now I could be completely wrong about this. And I know its dmax. But it looks like 97L is pulling the clouds/convection from the NW trying to wrap them around itself. Anyway its interesting. :)
Is shear suppose to be high in the carib.? If it's as high as they say it's suppose to be then this is the final hoorah for 97L and the wave out behind it could maybe become 98L.
Quoting weatherwatcher12:

When cloud tops cool and convection explodes. Strongest just before suunrise
DMAX is this Dirunal Maximum ?
Quoting willdunc79:
Is shear suppose to be high in the carib.? If it's as high as they say it's suppose to be then this is the final hoorah for 97L and the wave out behind it could maybe become 98L.
Looks like the upper level feature to the north is slightly pulling away,in which 97l might enter a area of favorable conditions???
Quoting weatherwatcher12:
I think I see what could be an anti-cyclone forming in the central Caribbean
Looks like this is true,after 97L goes by the upper air feature it might make it into a anticyclone,which may at 1st be detrimental then more positive for growth..I post at this time of the morning in case Im wrong ,not many viewers..LOL
good morning from Barbados

It's raining very heavily here now along with occasional gusty winds. Will get worse as the day goes on....
The NHC says 97L is becoming less organised. What are they talking about? Convection seems to have flared up in just the last two hours.
India Meteorological Department
Tropical Cyclone Bulletin Number TWO
DEPRESSION BOB03-2009
11:30 AM IST July 20 2009
===================================

Subject: Depression over northwest Bay of Bengal

At 6:00 AM UTC, Depression BOB03-2009 over northwest Bay of Bengal remained practically stationary and lay centered near 21.0N 88.5E, about 120 km southeast of Digha, 160 km east-southeast of Balasore and 200 km southwest of Khepupara (Bangladesh).

The system is likely to intensify further and move in a west-northwesterly direction and cross north Orissa-West Bengal coast between Balasore and Digha today

2175. MahFL
Dr M says conditions will improve then get a lot worse, 30 kts of shear will kill 97.
don't think it is going to become a deep depression with the way it looks now.
Quoting AstroHurricane001:
The NHC says 97L is becoming less organised. What are they talking about? Convection seems to have flared up in just the last two hours.


That convection is induced by diurnal maximum and upper level diffluence. If it can make it through today, then we have something to watch.
The storm is currently under about 20 to 25kt shear about 10kt more than i expected it to be tonight.Shear has reached its max for the enxt 3 to 4 days over this system.SShear will begin lifting today from the latest runs of wrf model.
morning
convection is once again on the increase with 97L. this morning"s infra red pics are showing that 97L was able to fight off the high shear and retain it"s structure. water vapour loops show that the system is now at the base of the trough which is giving it some breathing space. last night 97L moved southwest for awhile but has resumed a west course shear is still 20 knots over the system and that will prevent much organisation. deveopment or not the system will bring heavy rains to barbados and the central windwards with gusts near storm force, most of today and a portion of tomorrow
Good Morning Barbados, our system seems to have slowed a bit and convection is firing again as we hit DMAX. Rotation is still evident and she's in the sweet spot now, should be an interesting morning.

Current conditions are cloudy with light winds ENE with periods of heavy rain.

Info taken from Station 41101

Wind Direction (WDIR): E ( 80 deg true )
Wind Speed (WSPD): 22.9 kts
Wave Height (WVHT): 6.6 ft
Dominant Wave Period (DPD): 7 sec
Atmospheric Pressure (PRES): 29.90 in
Pressure Tendency (PTDY): +0.02 in ( Rising )
Air Temperature (ATMP): 81.3 °F
Water Temperature (WTMP): 81.5 °F
Dew Point (DEWP): 75.6 °F
Heat Index (HEAT): 87.8 °F
Combined plot of Wind Speed, Gust, and Air Pressure
raining here with strong wind gusts...
remember old rule if tw does not develop before the islands it wont
the wave @ 32w 7n could/should become 98L sometime today if it sticks to the trend of how it's doing now.
true but Leftovers not def. written in stone
only thing written in stone around here is storm top. your right will need west winds for the next step.
2188. beell
Tropical Update:
Quiet.
Quoting leftovers:
remember old rule if tw does not develop before the islands it wont


rgr that.


eastern carrib is the dead zone...
Whew! Looks like 97L is walking headlong into a gale in November. Look at her hair fly!
hey there jeff how update that wundermap love this addition but its only good if it is up to date
bright and sunny with winds of 15 mph this carnival monday. few are are inform about 97L and the impending weather. it will be a total surprise when the weather starts to go down hill
2194. WxLogic
Good Morning...
Hi Wx,
After more rambling about shear in a day the end result is that 97L is still there effected by shear but there.
I think we may get a little surprise from 97L. It's still holding on fairly well in my opinion.
2197. SLU


No closed surface low but unflagged tropical storm force winds! Plus it appears to be getting better organised on satellite pictures.

Morning guys
Quoting Weather456:
Good Morning;

Tropical Invest 97L heads for the Windward Islands



Good update W456, Have to say I follow your post closely.
group question. How can you tell when a tropical wave/system has convection that is from shear versus building it's own convection?
2200. crownwx
Crown Weather Tropical Weather Discussion: Link
2201. WxLogic
Seems 97L has finally hit the trough.

Now one interesting thing to note is that the time and location of this meeting point should prove interesting... since in my point of view 97L is in the eastern side of the trough which at this time is the worst part and later today it should a not so head on position with the shear... so should be interesting to see if the DMAX/Diffluence induced convection can stick around while it enters the E/C Carib. Of course not saying conditions are favorable in the CARIB as there's still shear left in there...

Also just in case... I've combined the latest 850MB through 500MB level VORT MAX charts and you can see the mid level shear has been displaced from the low shear VORT MAX due to shear.

Quoting willdunc79:
group question. How can you tell when a tropical wave/system has convection that is from shear versus building it's own convection?


Upper diffluence enhanced convection has little surface convergence and plenty upper divergence

Self-induce convection is surrface based hence surface convergence is often high or exceeds upper divergence.

2204. MahFL
"The storm is currently under about 20 to 25k..."

What storm ? It's a tropical wave right now. Not even a depression.....
Save the word "Storm" for the correct meteologial entity.
2205. WxLogic
Quoting sporteguy03:
Hi Wx,
After more rambling about shear in a day the end result is that 97L is still there effected by shear but there.


Hehe... Hi.

Yeah... but it is good that shear conflicts rise since that's the only way to clear up misconceptions about it, so people can be in the same page in regards certain topics. :)
so in layman terms wxlogic what are you saying?
So whats the guess on the NHC at 8. Its currently pouring with rain here in Barbados. I am in the south of the island
2208. SLU


Anyone living in Barbados, St. Lucia, St, Vincent & Martinique may want to treat this system with respect. Interesting to hear the NHC's comments in a few minutes.

13N/57W, quite a few 35-40mph winds .
2210. crownwx
Crown Weather Tropical Weather Discussion: Link
2211. Mikla
97L with latest SSTs, Water Vapor image, and some 00Z models...
2212. IKE
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON JUL 20 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND SHOWERS CONTINUE IN ASSOCIATION WITH A TROPICAL WAVE
LOCATED A COUPLE HUNDRED MILES EAST OF THE WINDWARD ISLANDS.
UPPER-LEVEL WINDS ARE EXPECTED TO REMAIN UNFAVORABLE FOR
DEVELOPMENT OF THIS SYSTEM FOR THE NEXT COUPLE OF DAYS. REGARDLESS
OF DEVELOPMENT...LOCALLY HEAVY RAINFALL AND GUSTY WINDS WILL AFFECT
THE WINDWARD ISLANDS DURING THE NEXT DAY OR SO AS THE WAVE MOVES
WESTWARD AT 15 TO 20 MPH. THERE IS A LOW CHANCE...LESS THAN 30
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
Quoting SLU:


Anyone living in Barbados, St. Lucia, St, Vincent & Martinique may want to treat this system with respect. Interesting to hear the NHC's comments in a few minutes.

Wow!! We must have posted quikscat at same time basically.
2214. WxLogic
Quoting willdunc79:
so in layman terms wxlogic what are you saying?


Shear has decouple the once coupled Vorticity engines that where helping the tropical system get organized. If they're not stacked together then you won't see organization needed for a TD to even develop.

Of course there are other ingredients... but this one should over one of them.
2215. SLU
000
ABNT20 KNHC 201140
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON JUL 20 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND SHOWERS CONTINUE IN ASSOCIATION WITH A TROPICAL WAVE
LOCATED A COUPLE HUNDRED MILES EAST OF THE WINDWARD ISLANDS.
UPPER-LEVEL WINDS ARE EXPECTED TO REMAIN UNFAVORABLE FOR
DEVELOPMENT OF THIS SYSTEM FOR THE NEXT COUPLE OF DAYS. REGARDLESS
OF DEVELOPMENT...LOCALLY HEAVY RAINFALL AND GUSTY WINDS WILL AFFECT
THE WINDWARD ISLANDS DURING THE NEXT DAY OR SO AS THE WAVE MOVES
WESTWARD AT 15 TO 20 MPH. THERE IS A LOW CHANCE...LESS THAN 30
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BRENNAN


oh well ..
2216. SLU
Quoting stormpetrol:

Wow!! We must have posted quikscat at same time basically.


lol .. yeh .. pretty good wind huh?
No the vorcity is deffinly still there
Morning all!
Quoting IKE:
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON JUL 20 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND SHOWERS CONTINUE IN ASSOCIATION WITH A TROPICAL WAVE
LOCATED A COUPLE HUNDRED MILES EAST OF THE WINDWARD ISLANDS.
UPPER-LEVEL WINDS ARE EXPECTED TO REMAIN UNFAVORABLE FOR
DEVELOPMENT OF THIS SYSTEM FOR THE NEXT COUPLE OF DAYS. REGARDLESS
OF DEVELOPMENT...LOCALLY HEAVY RAINFALL AND GUSTY WINDS WILL AFFECT
THE WINDWARD ISLANDS DURING THE NEXT DAY OR SO AS THE WAVE MOVES
WESTWARD AT 15 TO 20 MPH. THERE IS A LOW CHANCE...LESS THAN 30
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.


Another long day of shear debate ahead
Shear will begin to weaken today starting 12z to 18z.
good morning everyone
WHAT THE HELL IS GOING ON WITH 97L!!!!!!!!!!!!!!
Quoting Acemmett90:
No the vorcity is deffinly still there

the vortcity goes from 850 all the way down to 500
Quoting wunderkidcayman:
good morning everyone
WHAT THE HELL IS GOING ON WITH 97L!!!!!!!!!!!!!!

No Clue
2224. Mikla
Plot with Upper Shear and 850 mB Vorticity. Tear Drop marke is approx location of 97L...
2225. SLU
Quoting alaina1085:
Morning all!


morning alaina .. where are you from?
Good morning from south Texas!

You know a drought is pretty bad when you find yourself hoping that a tropical system heads your way just so you get any sort of rain at all!

We've only had 3 inches of rain since last August...driving down the roads you only see dead grass and brown trees with no greenery for miles and miles and miles when normally it is lush and green. Even the prickly pear cactus is a wilted sickly tan/yellow color.

Oh, and hello to those that remember me from last year!
NHC has continue to keep this as a wave with little development . one thing i am sure we here in St L ucia will be in for some very terrible weather later today into tomorrow.
hope carnival revellers are tuned to this developing situation
Quoting SLU:


morning alaina .. where are you from?


Southeast Louisiana. Gonzales to be exact. A small town between Baton Rouge and New Orleans. :)
Quoting stoormfury:
NHC has continue to keep this as a wave with little development . one thing i am sure we here in St L ucia will be in for some very terrible weather later today into tomorrow.
hope carnival revellers are tuned to this developing situation
Is this a Invest anymore?Do they drop it when they dont update the graphics?
Quoting WildHorseDesertTx:
Good morning from south Texas!

You know a drought is pretty bad when you find yourself hoping that a tropical system heads your way just so you get any sort of rain at all!

We've only had 3 inches of rain since last August...driving down the roads you only see dead grass and brown trees with no greenery for miles and miles and miles when normally it is lush and green. Even the prickly pear cactus is a wilted sickly tan/yellow color.

Oh, and hello to those that remember me from last year!


3 inches of rain since LAST august?? Thats crazy... sorry to hear that.
2231. IKE
Quoting sporteguy03:


Another long day of shear debate ahead


Fortunately I won't be here all day to read it...lol....

System isn't going to form anytime soon. Watch out for heavy rains and gusty winds though.

50 days down.
133 to go.
The sun is shining here in Barbados again :(
Quoting IKE:


Fortunately I won't be here all day to read it...lol....

System isn't going to form anytime soon. Watch out for heavy rains and gusty winds.

50 days down.
133 to go.

wait a second doesn't this thing have winds 25mph or higher thsi is a depression
IT is still an invest but in the met terms and to descibe it on the surface maps it is a trpical wave
the rain is starting to fall here again...very overcast outside
2236. IKE
Quoting Acemmett90:

wait a second doesn't this thing have winds 25mph or higher thsi is a depression


It's a tropical wave...
2237. SLU
Quoting alaina1085:


Southeast Louisiana. Gonzales to be exact. A small town between Baton Rouge and New Orleans. :)


That's good .. how's the weather over in Gonzales this morning?
Quoting IKE:


It's a tropical wave...
Quoting Acemmett90:

wait a second doesn't this thing have winds 25mph or higher thsi is a depression


If that was the only criteria for a tropical depression we would have one in florida most days during the summer. There is a lot more to a tropical depression than 25 mph winds.
Quoting SLU:


That's good .. how's the weather over in Gonzales this morning?

Sun seems to be rising as we speak, should be another pleasent day... definite lay out weather! LOL

Quoting StormW:
Good morning alaina.


Good Morning Storm! How are you?
Quoting DaytonaBeachWatcher:


If that was the only criteria for a tropical depression we would have one in florida most days during the summer. There is a lot more to a tropical depression than 25 mph winds.

yah its has the vorcity
Good Morning Folks....."Ralph" is fighting an uphill battle this morning against the sheer (good call NHC) and that ULL that is sucking the life blood out of it right now but who knows what will happen down the road after it gets into the Caribbean....In the short term however, and regardless of short-term development issues, our friends in the Lesser Antilles need to batten down so to speak....A rain soaked/windy tropical wave is nothing to laugh at and will cause some flooding and mudslides down there.......
Has anyone noticed the fact that it's gaining latitude? That's really not good for it since shear increases as you head north.

Also from looking at early visible images it aappears as though the shear has killed the mid level low. All that's left at the moment is a fairly well organized highly sheared wave. Shear runs from 20kts south side of the wave to 30kts on the north side.
2245. SLU
Quoting stoormfury:
NHC has continue to keep this as a wave with little development . one thing i am sure we here in St L ucia will be in for some very terrible weather later today into tomorrow.
hope carnival revellers are tuned to this developing situation


Well development looks unlikely for today but the quikscat shows 30 - 40kt winds in the thunderstorms so it deserves a little more respect. It's one of the strongest invests of the entire season so far.
Quoting StormW:


It lacks a closed, low level circulation.

that was my reason for it not bieg reconised
Quoting weathermanwannabe:
Good Morning Folks....."Ralph" is fighting an uphill battle this morning against the sheer (good call NHC) and that ULL that is sucking the life blood out of it right now but who knows what will happen down the road after it gets into the Caribbean....In the short term however, and regardless of short-term development issues, our friends in the Lesser Antilles need to batten down so to speak....A rain soaked/windy tropical wave is nothing to laugh at and will cause some flooding and mudslides down there.......


Ralph?? ROFL...
Our 97L doesn't look that bad this morning it looks to have taken advantage of the Diurnal phase but the cloud pattern looks to be sheared one this will mostly likely have a hard time making it through the day
Quoting wunderkidcayman:
good morning everyone
WHAT THE HELL IS GOING ON WITH 97L!!!!!!!!!!!!!!
NOTHING! Feel Sorry For Those That Hang On Like This Is Some Kind Of Relationship; Counseling Would Be in Order For Some, I Think!
Good Morning, Looking at 97L now and winds are up on the quikscat and convection is definitely up on the DMAX even though its in a unfavorable area lets wait and see this just might surprise us.
2252. SLU
Quoting victoria780:
Is this a Invest anymore?Do they drop it when they dont update the graphics?


Yeh it will be reclassified at 12Z. Don't be surprised if the winds are increased to at least 30kts.
Quoting StormW:


I'm good! How about you and that cute little guy?


Oh he is good now, we had a rough night tho :/
2254. SLU
Quoting alaina1085:

Sun seems to be rising as we speak, should be another pleasent day... definite lay out weather! LOL



Good Morning Storm! How are you?


lol ok. it's sunny over here for now... waiting to see what 97L has to offer.
SLU what time is 12Z in EST?
Quoting SLU:


lol ok. it's sunny over here for now... waiting to see what 97L has to offer.


Where are you located?
Quoting canesrule1:
Good Morning, Looking at 97L now and winds are up on the quikscat and convection is definitely up on the DMAX even though its in a unfavorable area lets wait and see this just might surprise us.

you got a point
033

WHXX04 KWBC 200523

CHGQLM

ATTENTION...NATIONAL HURRICANE CENTER



NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR



TROPICAL DEPRESSION INVEST 97L



INITIAL TIME 0Z JUL 20



DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT

REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD

NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC

OFFICIAL FORECAST.





FORECAST STORM POSITION



HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)



0 12.1 54.2 280./17.1

6 11.2 56.6 250./25.8



STORM DISSIPATED AT 6 HRS AT THE ABOVE PSN.
It looks like its leaving shear behind?
2261. SLU
I am in St. Lucia. 12z is 8:00am EST
What does 12z mean?
Quoting stormsurge39:
It looks like its leaving shear behind?
no it's not, this is heading WNW (well at least the latitude is increasing northward) its only going to get itself in even more shear.
Quoting StormW:


Rough night...weatherwise?


No LOL.. I wish. Julian had an upset stomach, just put it at that..LOL.
the mid level circulation is now under the heaviest convection. leadind edge of 97L about 4 hrs away from SLU
Quoting SLU:
I am in St. Lucia. 12z is 8:00am EST


Ugh, your so lucky. You get to live in paradise everyday...
Shear does't look to be favorable for a good while and i see no evidence of an anticyclone developing so this thing would need a prayer don't get me wrong i've seen it happen before (We all remember Barry lol) It is pretty much a wait and see game...how is everyone this morning
It also looks like the whole system is still turning with alot of convection! Does its chances get any better if it survives today? someone please enlighten me.
How far away is the leading edge from Barbados? When should we start to see the effect? Right now it is a bit overcast but i can still see the sun here. It was pouring earlier but that has stopped.
Quoting StormW:


Hope he feels better.

Thanks Storm, me too.

Quoting louisianaboy444:
Shear does't look to be favorable for a good while and i see no evidence of an anticyclone developing so this thing would need a prayer don't get me wrong i've seen it happen before (We all remember Barry lol) It is pretty much a wait and see game...how is everyone this morning


Im doing fabulous, how about yourself :)
2272. SLU
Quoting alaina1085:


Ugh, your so lucky. You get to live in paradise everyday...


lol .... ever been to St. Lucia before?
I think Just east of bahamas looks interesting; if I was in Carolinas I'd keep an eye on this area moving your way.
Quoting SLU:


lol .... ever been to St. Lucia before?


Sadly no, I havent been out of the country yet. Something on my to do list in life. But I hear its beautiful.
2275. beell
2258. KOG,

Quite the model run. 97L last seen moving SW at 26 knots!



0 12.1 54.2 280./17.1

6 11.2 56.6 250./25.8

STORM DISSIPATED AT 6 HRS AT THE ABOVE PSN.
2276. SLU
The "z" in 12Z stands for Zulu time, its the same as GMT and UTC (Universal Time Coordinated)

Julie

Barbados should get some heavy wind and rains shortly.

The leading edge of the heavy convection is a few hours away from the rest of the islands.
Hanging around in SRQ, not fishing.
its call X97L NOW..
Does the GFS do anything with this system because the one i'm looking at drops the system immediately
2280. IKE
Quoting louisianaboy444:
Does the GFS do anything with this system because the one i'm looking at drops the system immediately


Nope.

Shows nothing through the rest of July...tropically.
Quoting sebastianflorida:
I think Just east of bahamas looks interesting; if I was in Carolinas I'd keep an eye on this area moving your way.

Yeah, I was looking at that also. A lot of moisture in that area.
Quoting IKE:


Nope.

Shows nothing through the rest of July...tropically.

Ike, so far your prediction for the season is coming true..lol.


Shear is having fun with 97
2284. SLU
Quoting alaina1085:


Sadly no, I havent been out of the country yet. Something on my to do list in life. But I hear its beautiful.


Ok. try a Caribbean cruise. You'll love it.
2285. IKE
Quoting alaina1085:

Ike, so far your prediction for the season is coming true..lol.


It'll ramp up in August. Mid-August through mid-October is when the action is...
Quoting SLU:


Ok. try a Caribbean cruise. You'll love it.


I plan on it, thanks.
who live in conn?? look at this rain storm..
Quoting weathermanwannabe:
Good Morning Folks....."Ralph" is fighting an uphill battle this morning against the sheer (good call NHC) and that ULL that is sucking the life blood out of it right now but who knows what will happen down the road after it gets into the Caribbean....In the short term however, and regardless of short-term development issues, our friends in the Lesser Antilles need to batten down so to speak....A rain soaked/windy tropical wave is nothing to laugh at and will cause some flooding and mudslides down there.......
not that bad it will fill up the cisterns
Quoting stormsurge39:
It also looks like the whole system is still turning with alot of convection! Does its chances get any better if it survives today? someone please enlighten me.

97L is not in an environment conducive to tropical development because the shear is just too high. You can expect rain, some gusty winds, but nothing tropical force IMHO.
Quoting Orcasystems:


Shear is having fun with 97


lol
This could possibly be 97L's last day of existence we will have to see! I'm out like a fat kid in dodgeball see you guys at noonish!
97L has proven to be real sneaky, you have to watch anything thats sneaky.
One possible path takes 97L right towards Southeast Florida.
Quoting leftovers:
not that bad it will fill up the cisterns


Thanks......I did not know if you Folks down there needed more rain or not....Hope it's not too bumpy for you however.
Quoting hurricaneben:
One possible path takes 97L right towards Southeast Florida.


The present early Tracks go from as far as south of Cancun to missing Florida to the east... so basically... pick a spot.
AL, 97, 2009072012, , BEST, 0, 131N, 576W, 25, 1010,
Quoting Orcasystems:


The present early Tracks go from as far as south of Cancun to missing Florida to the east... so basically... pick a spot.


I'm thinking missing Florida to the east as it will probably get snatched into the pooling energy over the Bahamas.
TAFB, GR, VI, 5, 1515 /////, , , GOES12, CSC, T, DT = 1.5 BASED ON 0.3 BANDING
this 97L is driveing us all nuts


1st its gos poof



then it comes back then it gos poof so on so on so on
00Z GFS shear forecast showed low to moderate shear in 97L's path...even though thats not what it looks like right now...
2302. SLU
Quoting extreme236:
AL, 97, 2009072012, , BEST, 0, 131N, 576W, 25, 1010,


thanks. 120 miles east of Barbados.
Blog Update
Reflector site for those at work, which includes Weather456, daily update.


AOI

AOI

AOI
we haven't been driven this crazy since pre Dolly didn't form
Quoting Orcasystems:


The present early Tracks go from as far as south of Cancun to missing Florida to the east... so basically... pick a spot.


This got my attention...I know. I know. Get out the dart board. LOL. :)

CMC strait to Louisiana.



Link
yeay! texas finally getting some rain...
Link

it's going to be a wet day in Central Fla too.
Quoting stormsurge39:
What does 12z mean?


One of the problems of collecting Weather observations is that it is always changing and weather observation sites are spread across 24 major different "local times" around the globe. ( Believe it or not there are some local time zones that are 30 and even 15 minutes different than the one next to it)

To get a "Snap shot" of the world's weather, the powers that be agreed a long time ago that weather observers would take observations at "Synoptic Times" That is at the same point in time around the world. The agreed upon times for standard observations (no pending major weather activity) are 0000, 0600, 1200, 1800 UTC This standard is called Coordinated Universal Time, abbreviated UTC. This was formerly known as Greenwich Mean Time (GMT). Other terms used to refer to it include "Zulu time" (Z), "universal time," and "world time."

All of these are based on the (local)time it at Greenwich, England, which is located on the zero degree meridian (longitude)(from when the British Navy ruled the seas)

see http://www.dxing.com/utcgmt.htm
Good morning everyone! I am currently in La Romana, Dominican Republic, and glad to see that 97l isn't anything to worry about since it's moving in my direction... but I am looking forward to its arrival (as an open wave I believe) to my area sometime tomorrow evening. These tropical waves can actually bring very high winds and extremely heavy rain to the islands... nice to see in a place that doesn't get many interesting storms.
2309. SLU
Quoting extreme236:
TAFB, GR, VI, 5, 1515 /////, , , GOES12, CSC, T, DT = 1.5 BASED ON 0.3 BANDING


more evidence that it's better organised than the hurricane center believes.
Quoting extreme236:
TAFB, GR, VI, 5, 1515 /////, , , GOES12, CSC, T, DT = 1.5 BASED ON 0.3 BANDING


What does that mean? TAFB is a new one to me. :)
Quoting FLWeatherFreak91:
Good morning everyone! I am currently in La Romana, Dominican Republic, and glad to see that 97l isn't anything to worry about since it's moving in my direction... but I am looking forward to its arrival (as an open wave I believe) to my area sometime tomorrow evening. These tropical waves can actually bring very high winds and extremely heavy rain to the islands... nice to see in a place that doesn't get many interesting storms.

Don't rely on this site for weather information. Check with the NHC and your local weather authorities. Most of us, including me, just speculate and are often wrong!

Dr. Masters is usually right though. You should check back later to see what he has to say. I think he'll update his blog today.
DT=2.0 and we have TD2
Quoting Chicklit:

Don't rely on this site for weather information. Check with the NHC and your local weather authorities. Most of us, including me, just speculate and are often wrong!

Dr. Masters is usually right though. You should check back later to see what he has to say. I think he'll update his blog today.
The Dominican weather service is no help to me. Their office "onamet" lacks detail and is often very outdated and horribly inaccurate.
the wind shear is getting to high for this storm i see 40knots wind shear up north of the storm..
Quoting SLU:


more evidence that it's better organised than the hurricane center believes.


That data is from the hurricane center.
Quoting stoormfury:
DT=2.0 and we have TD2


Not without an organized llc. Which is not there. The mid level low doesn't even look like it's there anymore.
2317. SLU
Quoting nrtiwlnvragn:


That data is from the hurricane center.


yeh it goes back to 456's point yesterday about the lack of consistency
Quoting HurricaneKing:


Not without an organized llc. Which is not there. The mid level low doesn't even look like it's there anymore.
no more mid level low anymore.
Quoting SLU:


yeh it goes back to 456's point yesterday about the lack of consistency


Which I respectfully disagree with.
Quoting homelesswanderer:


What does that mean? TAFB is a new one to me. :)


TAFB is an organization that is basically the NHC, but it is a Dvorak Satellite Intensity estimate to determine the organization and strength of a disturbance or tropical cyclone.
Quoting stoormfury:
DT=2.0 and we have TD2


Fay formed last year when her estimates were up to 2.5 and higher, so those dont mean anything without an LLC.
example of why the Dominican Weather Service fails:

http://www.onamet.gov.do/pronostico.php?n=1392
Quoting extreme236:


TAFB is an organization that is basically the NHC, but it is a Dvorak Satellite Intensity estimate to determine the organization and strength of a disturbance or tropical cyclone.


Oh. Ok. TYVM. :)
I thought nothing was suppose to remain with 97L after reading the 2000 posts yesterday maybe later in the day??
Quoting sporteguy03:
I thought nothing was suppose to remain with 97L after reading the 2000 posts yesterday maybe later in the day??


you know how it works on this site, most dont know how to just go with the flow, instead they jump to conclusions, assume way too much and in the end make themselves look like idiots

Quoting sporteguy03:
I thought nothing was suppose to remain with 97L after reading the 2000 posts yesterday maybe later in the day??
That's when the convection was down and everyone thought it was all over, the reason the convection wasn't there was the DMIN, now that it has passed the DMAX stage the convection is back, its just one of those ordinary stages a wave goes through.
most of the convection from 97L is shear induced today, it is a way for weak disturbances like this to survive shear like this

it has happened many many times before, if this were a naked system than you could be about to pull the plug, that is clearly not happening
Good Morning folks
Quoting sporteguy03:
I thought nothing was suppose to remain with 97L after reading the 2000 posts yesterday maybe later in the day??


That is exactly why anyone worth their salt on here, all the regulars, all the folks with the experience to make an educated guess or opinion, will tell you that it's not over until it's over, that we have to wait and see and that none of them are psychic and nobody is infallible.
wow looks like 97L had the same fate as the wave before it. whatever circulation it had must be gone now with that shear. shear is just too high for anything to form at all, and it's already late july. typical of an el nino year. many more invests to come will also be ripped apart by shear.

EDIT: however just because it met the same fate doesnt mean shear wont lessen up and it wont get started again in the central caribbean.. shear doesnt harm tropical waves it just prevents them from forming. it'll still be around here for a while and people should keep an eye on it
Did anyone happen to look at TWC tropical updates last night? Anyway, they spent 3 min having people write in to decide when is it too cold for the pool and when is it too cold for ice cream. Maybe it's me, but what the hell dose that have to do with the tropics? I mean it's stupid, and then she rushed through the tropical update.
Quoting HurricaneSwirl:
wow looks like 97L had the same fate as the wave before it. whatever circulation it had must be gone now with that shear. shear is just too high for anything to form at all, and it's already late july. typical of an el nino year. many more invests to come will also be ripped apart by shear.

EDIT: however just because it met the same fate doesnt mean shear wont lessen up and it wont get started again in the central caribbean.. shear doesnt harm tropical waves it just prevents them from forming. it'll still be around here for a while and people should keep an eye on it


It didnt meet any fate yet, 97L is still slive and kicking

there is that "assuming" that I was talking about before
Quoting InTheConeOIO:
Did anyone happen to look at TWC tropical updates last night? Anyway, they spent 3 min having people write in to decide when is it too cold for the pool and when is it too cold for ice cream. Maybe it's me, but what the hell dose that have to do with the tropics? I mean it's stupid, and then she rushed through the tropical update.


LOL... i dont watch it. theres really no point in the weather channel, its boring and you can just look at your radar on the internet... and no commercials!
those models keep on getting closer to S-FL, scaring me a bit now.
2336. Grothar
I know that the attention is on 97L, but does anyone have an opinion on the blob which moved off the African Coast yesterday? While it is at a low altitude and not well formed, it appears to have maintained a consistent moisture field. Perhaps my observation is premature; just interested.
Quoting leftovers:
remember old rule if tw does not develop before the islands it wont


actually the old rule is if a TW doesnt develop before the islands it wont develop before it gets to the Western Caribbean

doesnt mean it wont develop at all
Quoting BurnedAfterPosting:


It didnt meet any fate yet, 97L is still slive and kicking


remember the wave before it tho? it ran into the exact same spot except a bit higher latitude and had the exact same thing happen.. shear. alive and kicking? it lost whatever circulation it had and all of its convection is either from dmax or being shear induced.

im not necessarily saying its over... like I wrote in my edit, shear doesnt harm waves it just prevents a cyclone from forming.. if shear does decide to lessen up it'll still be there, but it might get deactivated and then reactivated again lol.
Quoting InTheConeOIO:
Did anyone happen to look at TWC tropical updates last night? Anyway, they spent 3 min having people write in to decide when is it too cold for the pool and when is it too cold for ice cream. Maybe it's me, but what the hell dose that have to do with the tropics? I mean it's stupid, and then she rushed through the tropical update.

The Weather Channel is becoming more stupid each day.It is becoming of a more reality/entertainment show then a weather news channel.
2340. surfmom
97L ain't over till the fat lady sings..... though she seems to be choking a bit now...

memories of Dolly --some of the most beautiful groundswell I have ever surfed on the Gulf

Good rainstorm this AM in SRQ/FL -- hiding out at the house b/4 I head out East and work the horses. going to a MUD FEST, MOSQUITO BANQUET day for sure....but it beats sitting in an office, under fluorescent light --least for me.

All water holes/ponds are FULL to the top -- haven't seen that in several years......well... the year of Charlie,Frances & Jeanne --so I wonder if that's a ....clue

CHICKLIT -- GOOD to see you.....
I found a SHIP around Barbados showing only 2 knot winds but pressure was at 29.83, something is going on there.
2342. surfmom
Quoting StormFreakyisher:

The Weather Channel is becoming more stupid each day.It is becoming of a more reality/entertainment show then a weather news channel.


the continued dumbing down of America -- distraction & diversion..............people don't wanna think anymore.... 'cept those of us here -- we may fight, but at least we're thinking LOL
97 is not going to die, once it gets thru today lookout!!!! The last wave that was in that area looked like it was taking on more shear than 97 is. Also no other wave coming off africa this year has done this good.Dont let your guard down.
Quoting StormFreakyisher:

The Weather Channel is becoming more stupid each day.It is becoming of a more reality/entertainment show then a weather news channel.


And now they add Al Roker, the Ed McMahon of weather...jeez.

Does anybody know why all of the HiDef radar sites are down?
2346. Drakoen
Not much change with 97L. The reason for the convection you are seeing is is because of the systems location at the base of the trough producing upper level diffluence as well being near the northeastern coast of South America. Some of the models indicate that shear may become more favorable for development in 2 days.
Quoting StormW:


TAFB= Tropical Analysis Forecast Branch


morning StormW, can you please shed some light on 97L

It is being called dead as a doornail by so many people lol, thought maybe you could help us out and give us a more enlightened opinion


I feel the convection that is being induced by the shear will help 97L to survive somehow
Quoting StormW:


TAFB= Tropical Analysis Forecast Branch
Hey there Storm, how you doing?
Quoting Drakoen:
Not much change with 97L. The reason for the convection you are seeing is is because of the systems location at the base of the trough producing upper level diffluence as well being near the northeastern coast of South America. Some of the models indicate that shear may become more favorable for development in 2 days.


morning Drak, yea I agree, seems to me that it is fighting fairly well though, not just dying out
Quoting StormW:


TAFB= Tropical Analysis Forecast Branch


Thanks Storm. :)

Quoting canesrule1:
those models keep on getting closer to S-FL, scaring me a bit now.


No need to worry; this is not going to make it to South Florida.......Don't take my word for it...You only have to worry down the road when NHC officially declares a tropical storm or hurricane watch for your area.......On a related note, if you have a hurricane plan in place and have bought supplies in case, there is no need to worry....Take care of these items during this "lull" if you have not already done so...........Dont' Worry...Be Happy...... :)
1010 pressure was the last one that was posted and its the lowest yet.
Okay I have two questions.Is all that rain and cloudiness east of the Bahamas the remnants of the tropical wave that was sheared apart and is interacting now with a frontal boundary that will make it form into somethin?And what will happen with the tropical wave in the mid atlantic that is still holding a pouch of thunderstorms?
2355. Drakoen
Quoting BurnedAfterPosting:


morning Drak, yea I agree, seems to me that it is fighting fairly well though, not just dying out


I don't think it's done yet.
i will
Quoting stormsurge39:
1010 pressure was the last one that was posted and its the lowest yet.
i posted a 29.83
NEW BLOG!!
Quoting StormW:


Good...you?
im doing good, following those models, just wondering do you believe we might have our first named system of the season with 97L or is this just going to die?
Ghotar- From now on anything that come out of Africa should be interesting, since we are approaching rapidly Cape VERDE season.
Good morning. I see 97L survived the night with the "dreaded" shear.

GFDL does not do cyclcogenesis, folks. 97L maintained despite the shear, still moving with steering mostly westerly, big convection there with dmax from all the lift. LLC? Can't see it. MLC, difficult too; but, I imagine it's still there - it's just grappling with how to manage all that convection now. ;)

2363. Grothar
I agree with the comments on The Weather Channel. One must infer from their format that they believe they are the focus of the show, when in fact the weather is secondary. Weather, in itself is dynamic. They interject themselves in front of the maps so you cannot see the "massive storms and fronts, etc". It should be more informative and precise.
2364. Mikla
97L with some models and mid & upper shear...
2365. msphar
Burned - you still believe in your Westward thesis or was it SW? Looks to me like it gained a degree Northwards overnight while it moved West 7.5 degrees.