Tropical Depression Seven forms

By: Dr. Jeff Masters , 2:25 PM GMT on August 14, 2011

Share this Blog
14
+

The latest in our unusual number of weak tropical cyclones this season, Tropical Depression Seven, has formed to the southeast of Bermuda. Unless you live in Bermuda, TD 7 is not going to be a concern. Radar out of Bermuda shows an area of rain on the northern side of TD 7 beginning to approach the island, and rain from the storm will likely affect the island tonight and on Monday. TD 7 is not well-organized, and has only limited heavy thunderstorms, as seen on visible satellite images. While wind shear is a low 5 - 10 knots, dry air surrounds TD 7, and is keeping the storm from intensifying. None of the computer models foresee that TD 7 will ever become more than a weak tropical storm.


Figure 1. Morning satellite image of TD 7.

92L
TD 7 isn't the only system Bermuda needs to watch, Invest 92L is a day behind it, and will follow a path very similar to TD 7's. The disturbance will pass close to Bermuda on Tuesday, bringing the island a second round of tropical rains. However, Invest 92L is very disorganized, as seen on recent visible satellite loops. Dry air and close proximity to TD 7 will likely keep 92L from showing significant development over the next two days, with NHC giving the system just a 30% chance of developing into a tropical depression by Tuesday morning.

Elsewhere in the tropics
The disturbance midway between the Lesser Antilles Islands and the coast of Africa we've been tracking over the past few days, Invest 93L, has fallen apart and is no longer a threat to develop. This system will need to be watched once it enters the Caribbean later this week, though. None of the reliable models for predicting tropical cyclone formation predict development of this system or any new disturbances over the coming week.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 875 - 825

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

Quoting Vincent4989:

that's also made up information.


No, it isn't. We do have 96L.
Member Since: Posts: Comments:
Quoting Tropicsweatherpr:


At 18z surface analysis,they put the wave axis at 50W.



Ah, okay. I couldn't find the 18z, or I would have posted it.
Member Since: March 7, 2007 Posts: 597 Comments: 21094
Vincent4989: you will find 96L at 67N, 638W
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting washingtonian115:
Mmmm Gert reminds me of Shary from last year.The NHC forecasted Shary to only get up to a marginal or strong tropical storm.But it happen to reach hurricane intensity.I wouldn't be surprised if it happen in Gert's case.


If I'm not mistaken, the environment surrounding Shary was a bit more conducive, as there was no real semblance of dry air. Her satellite presentation definitely wasn't one indicative of dry air intrusion.
Member Since: March 7, 2007 Posts: 597 Comments: 21094
871. j2008
Quoting Vincent4989:

that's also made up information.

Need the link to see for yourself??
Member Since: Posts: Comments:
Quoting Vincent4989:

that's also made up information.





NO its not we really do have 96L
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting MiamiHurricanes09:
North of HispaƱola btw.


Ohhhhh, Emily's granddaughter. Thank you :)
Member Since: Posts: Comments:
Quoting hunkerdown:
so is your brain
Oh nice come back!
Member Since: Posts: Comments:
866. j2008
Quoting Vincent4989:

It really doesn't exist. Its just made up by you and other wunderbloggers here.

AL, 96, 2011081418, , BEST, 0, 367N, 638W, 25, 0, DB. Oh yea Its real. LOL.
Member Since: Posts: Comments:
Quoting Vincent4989:


does not exist i checked out at navy site




yes it dos we do have 96L your not even looking
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting KoritheMan:


The actual wave axis is actually closer to 45W, as seen here:



At 18z surface analysis,they put the wave axis at 50W.

Member Since: Posts: Comments:
Quoting Hurricanes101:



AL, 96, 2011081418, , BEST, 0, 367N, 638W, 25, 0, DB, 0, , 0, 0, 0, 0,

You were saying?




lol
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting Tazmanian:




we do have 96L am not jokeing


does not exist i checked out at navy site
Member Since: Posts: Comments:
Quoting Tropicsweatherpr:
I am making an album blog of past famous and infamous hurricanes and typhoons.If any of you want to add pics,go ahead.

Link


Sweet. I didn't even know about this. Thanks for the enlightenment!
Member Since: March 7, 2007 Posts: 597 Comments: 21094
Quoting Vincent4989:

It really doesn't exist. Its just made up by you and other wunderbloggers here.



AL, 96, 2011081418, , BEST, 0, 367N, 638W, 25, 0, DB, 0, , 0, 0, 0, 0,

You were saying?
Member Since: Posts: Comments:
BEGIN
NHC_ATCF
invest_al962011.invest
FSTDA
R
U
040
010
0000
201108142020
NONE
NOTIFY=ATRP
END
INVEST, AL, L, , , , , 96, 2011, DB, O, 2011081418, 9999999999, , , , , , METWATCH, , AL962011
AL, 96, 2011081418, , BEST, 0, 367N, 638W, 25, 0, DB, 0, , 0, 0, 0, 0,
Member Since: Posts: Comments:
Quoting Vincent4989:

It really doesn't exist. Its just made up by you and other wunderbloggers here.


It exists, it's on the navy site. I just can't figure out where it is lol.
Member Since: Posts: Comments:
Quoting bappit:
I see it said often that:

"Tropical systems are mother nature's way of transporting heat from the tropics towards the poles."

I think that was in my Golden Nature Guide to Weather back in 1964? Some similar book if not there. I think it is a lot of balogna.

Baroclinic systems are the go-to guys for transporting heat poleward. They aren't limited to oceans with high SST's, they don't occur only in certain times of the year--though the most intense mid-latitude systems do occur in winter--and they often are a lot larger than tropical cyclones. Tropical cyclones in fact are rare events compared to mid-latitude cyclones. Barotropic systems primarily transport heat vertically--but I'll bet that the vertical transport of heat by baroclinic systems still dominates over barotropic systems.

Perhaps the rationale behind this kind of statement is that people want to assign some higher purpose to a force that can be so destructive. If things did work that way, then what is the purpose of drought?


But hurricanes are gigantic heat engines that cool the tropics and do go poleward.
Member Since: August 19, 2008 Posts: 0 Comments: 825
Mmmm Gert reminds me of Shary from last year.The NHC forecasted Shary to only get up to a marginal or strong tropical storm.But it happen to reach hurricane intensity.I wouldn't be surprised if it happen in Gert's case.
Member Since: Posts: Comments:
Quoting deaddude21:

Or a big spin/more well defined spin...

There is nothing above Hispaniola other than a thunderstorm.


North of HispaƱola btw.
Member Since: Posts: Comments:
916
WFUS52 KRAH 142224
TORRAH
NCC067-142315-
/O.NEW.KRAH.TO.W.0043.110814T2224Z-110814T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
624 PM EDT SUN AUG 14 2011

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* TORNADO WARNING FOR...
FORSYTH COUNTY IN CENTRAL NORTH CAROLINA

* UNTIL 715 PM EDT

* AT 623 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
TORNADO OVER DONNAHA...OR OVER KING...MOVING SOUTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
RURAL HALL...
PFAFFTOWN...STANLEYVILLE...
WINSTON-SALEM...
SEDGE GARDEN...

Member Since: Posts: Comments:
Quoting ncstorm:
From our local TV Weather..

STORMTRACK 3: A cell capable of producing a tornado is moving east at 15 mph over Holly Shelter Game Land.

hunker down good luck
Member Since: Posts: Comments:
Quoting Vincent4989:

It really doesn't exist. Its just made up by you and other wunderbloggers here.




we do have 96L am not jokeing
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting ackee:
EX 93L nearing 60 W still not organize give it currenT state I am gviing up on EX 93L


The actual wave axis is actually closer to 45W, as seen here:

Member Since: March 7, 2007 Posts: 597 Comments: 21094
Quoting ncstorm:


Stay Safe!


Oh, I am. If there is any type of rotation or tornado, it is to the north of here. In fact, it isn't even raining here.
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:


Tornado Warning here, tornado reported on the ground.


wtf are you doing on the computer then?
Member Since: March 7, 2007 Posts: 597 Comments: 21094
Quoting hunkerdown:
so is your brain


+2

1 for each week lol
Member Since: Posts: Comments:
Quoting MississippiWx:


It's already being absorbed into Gert...check out the 850mb vort maps.



you cant tell by looking at 850 vort 92L is still there
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting bappit:
I see it said often that:

"Tropical systems are mother nature's way of transporting heat from the tropics towards the poles."

I think that was in my Golden Nature Guide to Weather back in 1964? Some similar book if not there. I think it is a lot of balogna.

Baroclinic systems are the go-to guys for transporting heat poleward. They aren't limited to oceans with high SST's, they don't occur only in certain times of the year--though the most intense mid-latitude systems do occur in winter--and they often are a lot larger than tropical cyclones. Tropical cyclones in fact are rare events compared to mid-latitude cyclones. Barotropic systems primarily transport heat vertically--but I'll bet that the vertical transport of heat by baroclinic systems still dominates over barotropic systems.

Perhaps the rationale behind this kind of statement is that people want to assign some higher purpose to a force that can be so destructive. If things did work that way, then what is the purpose of drought?


Tropical cyclones are much more effective in this endeavor, because they derive their vigor from the latent heat energy of the world's tropical oceans. On the contrary, baroclinic systems derive their energy from temperature and pressure differences, which doesn't make for an effective heat transfer.
Member Since: March 7, 2007 Posts: 597 Comments: 21094
I am making an album blog of past famous and infamous hurricanes and typhoons.If any of you want to add pics,go ahead.

Link
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:


Tornado Warning here, tornado reported on the ground.


Stay Safe!
Member Since: Posts: Comments:
Quoting extreme236:
92L is gonna need some distance from Gert if its going to develop.




yup but it may not be has close has you think it may be
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Quoting extreme236:
92L is gonna need some distance from Gert if its going to develop.


It's already being absorbed into Gert...check out the 850mb vort maps.
Member Since: Posts: Comments:
Quoting deaddude21:
The wave coming off Africa...is two weeks away.
so is your brain
Member Since: Posts: Comments:
Quoting AtHomeInTX:


Oh no. Hope it doesn't get too bad.


thanks!!
Member Since: Posts: Comments:
.

Member Since: May 21, 2006 Posts: 5091 Comments: 115357
92L is gonna need some distance from Gert if its going to develop.
Member Since: Posts: Comments:
836. j2008
Quoting Hurricanes101:


and yet you are complaining, kind of ironic to me ;)

Haha Yea I know, just felt like getting my point out. Lets get back to tropics, I think Gert will be an issue only for bermuda. 93L will probably become an issue for Mexico and possibly the US (need to watch out for that one) JMO, feedback is welcomed.
Member Since: Posts: Comments:
Quoting ncstorm:
From our local TV Weather..

STORMTRACK 3: A cell capable of producing a tornado is moving east at 15 mph over Holly Shelter Game Land.



Tornado Warning here, tornado reported on the ground.
Member Since: Posts: Comments:
Completely lost here. What's 96L?
Member Since: Posts: Comments:
Guys, wheres that 96L thingy you mentioning? it even doesn't exist.
Member Since: Posts: Comments:
Quoting ackee:
EX 93L nearing 60 W still not organize give it currenT state I am gviing up on EX 93L



nevere give up on a storm it will come back this give it time
Member Since: May 21, 2006 Posts: 5091 Comments: 115357
Given the fact that the environmental conditions are super-conducive for development over Gert - at least for the next day or so, due to the positioning of that trough - I wonder what her chances of rapid strengthening are? Judging by her satellite presentation, she's looking much better with each frame. And I think 92L is done, and is helping Gert be a much more formidable threat to Bermuda. I always thought 92L wouldn't survive a proximity that close unless Gert remained extraordinarily weak and puilled far enough away... but now it looks as if her strengthening is enough to unravel the Invest into her circulation.

Should be interesting to see how strong she gets once she hits Bermuda. She'll be no Fabian... not even close... but she has a very small chance to become a minimal hurricane, should she continue taking full advantage of the environmental conditions.
Member Since: Posts: Comments:
I see it said often that:

"Tropical systems are mother nature's way of transporting heat from the tropics towards the poles."

I think that was in my Golden Nature Guide to Weather back in 1964? Some similar book if not there. I think it is a lot of balogna.

Baroclinic systems are the go-to guys for transporting heat poleward. They aren't limited to oceans with high SST's, they don't occur only in certain times of the year--though the most intense mid-latitude systems do occur in winter--and they often are a lot larger than tropical cyclones. Tropical cyclones in fact are rare events compared to mid-latitude cyclones. Barotropic systems primarily transport heat vertically--but I'll bet that the vertical transport of heat by baroclinic systems still dominates over barotropic systems.

Perhaps the rationale behind this kind of statement is that people want to assign some higher purpose to a force that can be so destructive. If things did work that way, then what is the purpose of drought?
Member Since: Posts: Comments:
827. ackee
Quoting Tazmanian:
t-storms with ex 93L seem too be weaking some tonight but sould re fire later
EX 93L nearing 60 W still not organize give it currenT state I am gviing up on EX 93L
Member Since: Posts: Comments:
Quoting j2008:

People need to stop wishcasting for hurricanes, they will come, probably very soon in fact. The thing is, I've seen this happen so many times, people will wish for a hurricane so many times, and then a Cat 5 slams into the US and everybody complains about hurricanes. Its a sad fact of life, people love to complain. Dont want it to seem like I'm getting mad at anyone but I dont appriciate how people have been complaining last week. The hurricanes will come, please be safe everyone :).


Nobody is complaining. We are merely baffled.
Member Since: March 7, 2007 Posts: 597 Comments: 21094
that wave coming off Africa is very impressive
Member Since: Posts: Comments:

Viewing: 875 - 825

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.