97L fizzles; new Bahamas disturbance develops

By: Dr. Jeff Masters , 2:17 PM GMT on July 21, 2009

Share this Blog
2
+

A strong tropical wave (97L), now located just south of Puerto Rico, has grown disorganized today. Sustained winds as high as 26 mph were observed on Barbados, and 35 mph winds were observed on St. Lucia yesterday when 97L passed through the Lesser Antilles Islands. Wind gusts to 45 mph and heavy rain can be expected in the Dominican Republic and Puerto Rico this afternoon, and in Haiti and the southeastern Bahama Islands on Wednesday. However, 97L is under too much wind shear to develop, and shear will remain in the high 25 - 35 knot range over the disturbance over the next two days.


Figure 1. Today's disturbances to watch.

A new tropical disturbance has formed north of the central Bahama Islands, about 600 miles east of Miami. The thunderstorm activity is not yet very intense, but does cover a moderately large area. This morning's QuikSCAT pass showed winds of 20 - 25 mph, and no evidence of a circulation trying to form. This region is under about 20 - 25 knots of wind shear, and has the potential for some slow development over the next few days as it moves slowly northwards. The GFS and ECMWF models hint at the possibility that this system may attempt to organize into a tropical depression by Friday, off the coast of North Carolina.

I'll have an update Wednesday.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Sign In or Register Sign In or Register

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: 307 - 257

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 | 38Blog Index

Quoting Weather456:
the CFS/GFS model map is showing some good conditions for August 2009. Interesting month adhead. MJO also returning.


I put out there last night that we will get 5 named storms in August
Quoting jurakantaino:
folks,,here in South and west Puerto Rico winds 45mps gusting to 50 in squalls, it feels like a tropical storm. FAlling trees every where and electric failures.
wow, please stay safe, please keep us informed with the situation as it unfolds, thanks.
Member Since: Posts: Comments:
the CFS/GFS model map is showing some good conditions for August 2009. Interesting month adhead. MJO also returning.
Member Since: Posts: Comments:
Quoting reedzone:


not tonight, I meant eventually, must you always start an argument with me? LOL :P


Umm my bad, you were referring to another person..
oops.
Member Since: Posts: Comments:
Quoting jurakantaino:
folks,,here in South and west Puerto Rico winds 45mps gusting to 50 in squalls, it feels like a tropical storm. FAlling trees every where and electric failures.


Yikes, well keep us posted and I hope you get through ok
Quoting BurnedAfterPosting:


He is talking about the area around the Bahamas, not 97L
he is talking about both the areas.
Member Since: Posts: Comments:
Quoting reedzone:


not tonight, I meant eventually, must you always start an argument with me? LOL :P


not you lol, that was for canesrule that said shear would be 10 knots around 97L tonight
Quoting BurnedAfterPosting:
shear wont be 10 knots in that area tonight
yes it will buddy, its around 20-30 knots and its expected to fall around 20 knots in the next 9 hours.
Member Since: Posts: Comments:
Wow! Larry, Moe and Curly in the tropics!

You just don't know what they're going to do or what they're going to mess up!
Member Since: July 9, 2006 Posts: 184 Comments: 29610
In my July outlook, I gave a 60% chance of atleast 1 named storm. That 60% remains. Overall, May 15 forecast 12 named storms, that 12 named storms remain.

Prelimnary August outlook, 70% chance of atleast 2 named storm. That outlook will be issued next Saturday.
Member Since: Posts: Comments:
folks,,here in South and west Puerto Rico winds 45mps gusting to 50 in squalls, it feels like a tropical storm. FAlling trees every where and electric failures.
Member Since: July 31, 2008 Posts: 0 Comments: 730
Quoting canesrule1:
i could not agree more, bravo!!! thanks reedzone i needed someone to say that!!! now if we're wrong ill eat 867,983,217,998 crows remember, med-well


He is talking about the area around the Bahamas, not 97L
Quoting BurnedAfterPosting:
shear wont be 10 knots in that area tonight


not tonight, I meant eventually, must you always start an argument with me? LOL :P
Member Since: Posts: Comments:
Quoting reedzone:
20-30 knots of shear currently, that is expected to drop to 10 knots. This has a decent shot at becoming ANA, though models track 97L to that area around the same time frame that the disturbance could form. I think both of these disturbances with a stalling trough to the west will create our official first storm of the season.
i could not agree more, bravo!!! thanks reedzone i needed someone to say that!!! now if we're wrong ill eat 867,983,217,998 crows remember, med-well
Member Since: Posts: Comments:
Quoting Dar9895:
1983 was a very rare and unusual inactive season but this season could be double and far more active with a total of 12-15 tropical depression and 8-9 named storm (or perhaps more).


I believe it will be more like 14/7/4
Member Since: Posts: Comments:
Interesting night..... well i'm out.
Goodnight.
Stay safe all.
Member Since: Posts: Comments:
shear wont be 10 knots in that area tonight
NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 72 HOURS
FORECAST POSITION AT T+ 72 : 29.6N 78.9W

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
00UTC 24.07.2009 29.6N 78.9W WEAK
12UTC 24.07.2009 30.9N 77.1W WEAK WEAKENING SLIGHTLY
00UTC 25.07.2009 33.1N 77.3W WEAK INTENSIFYING SLIGHTLY
12UTC 25.07.2009 34.7N 76.1W WEAK INTENSIFYING SLIGHTLY
00UTC 26.07.2009 36.2N 74.6W WEAK WEAKENING SLIGHTLY
12UTC 26.07.2009 38.4N 73.3W WEAK INTENSIFYING SLIGHTLY
00UTC 27.07.2009 40.4N 71.8W WEAK WEAKENING SLIGHTLY


THIS INFORMATION IS PROVIDED AS GUIDANCE FOR TROPICAL CYCLONE
RSMCS. IT REQUIRES INTERPRETATION BY TROPICAL CYCLONE SPECIALISTS
AND SHOULD NOT BE CONSIDERED AS A FINAL PRODUCT


MET OFFICE, EXETER, UK

TOO 210438
Member Since: Posts: Comments:
20-30 knots of shear currently, that is expected to drop to 10 knots. This has a decent shot at becoming ANA, though models track 97L to that area around the same time frame that the disturbance could form. I think both of these disturbances with a stalling trough to the west will create our official first storm of the season.
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
yet you cant see that 97L is getting sheared?


LMAO

ok whatever, there are indications the area in the Bahamas is getting better organized, there are no indications 97L is
i know 97L is getting sheared badly i just know that by tonight the shear in that general area is going to be to around 10 knots.
Member Since: Posts: Comments:
1983 was a very rare and unusual inactive season but this season could be double and far more active with a total of 12-15 tropical depression and 8-9 named storm (or perhaps more).
Member Since: Posts: Comments:
Shear expected to let up thursday and Friday, that's when the models are forecasting development. So I suspect nothing until then

Member Since: Posts: Comments:
yet you cant see that 97L is getting sheared?


LMAO

ok whatever, there are indications the area in the Bahamas is getting better organized, there are no indications 97L is
The only thing "I can see clearly now" is that the areas around Cuba/Jamaica, Florida, and the Gomex are free of any significant rain or convection.....All that may change in the near future but there is no certainty of tropical develpment at the moment in both areas of interest........Basically, it's just one huge mess out there between PR and moving on North off the US seaboard.
Member Since: Posts: Comments:
283. Relix
Quoting cg2916:

Looks like a relocating center?


This is what I asked. It's not that it has a COC, but there's definitely some turning there.
Member Since: Posts: Comments:
Drak, both systems have remarkable lower level convergence. However, the one near the Bahamas is less sheared.



Member Since: Posts: Comments:
Quoting cg2916:

Looks like a relocating center?
No I was just pointing out best way to track it's direction at this time.
Member Since: August 10, 2007 Posts: 0 Comments: 3296
Quoting IKE:
GFS 12Z @ 120 hours....looks like a winter-time pattern. Virtually zero chance for anyone in the USA to be affected tropically.

The pattern won't allow it...sorry:(





That's a good thing. Why sorry? I hoping for something to track especially if it does not affect anyone.
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
intensely?

The shear isnt that bad in that area
The AOI in the bahamas seems be sheared strongly because you could see the clouds being ripped.
Member Since: Posts: Comments:
278. IKE
Quoting Dakster:
I like it IKE... No worries so far... Now if this pattern could hold through to say December 1 - that would be even nicer.


Yes it would.
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
intensely?

The shear isnt that bad in that area

It's 20-30 knots
Member Since: May 16, 2009 Posts: 1 Comments: 1231
276. 7544
all the convection is to the west of 97l so maybe thats where they may relocate it as it has been done with other systems before
Member Since: Posts: Comments:
Yes bahamas thing getting sheared strongly.Once shear increases more higher than 40kt it will die/rip bahamas blob.
Member Since: Posts: Comments:
the bahama area really looks disorganized,more so lately
Member Since: Posts: Comments:
NOUS42 KNHC 211230
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
0830 AM EDT TUE 21 JULY 2009
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 22/1100Z TO 23/1100Z JULY 2009
TCPOD NUMBER.....09-054

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY: POSSIBLE LOW LEVEL
INVEST NEAR 29N 76W AT 23/1800Z.
Member Since: Posts: Comments:
272. IKE
Quoting Patrap:
Looks more Like March on that one IKE.


GOM is off-limits for now.

All of that mess east of the USA will eventually get kicked north and NE.

If this pattern continues, good chance our season along the gulf-coast will be over by mid-October.

And I think the balance of July is about free and clear for us.

Member Since: Posts: Comments:
Quoting Patrap:


Pat can you please post the link for the satellite imagery on top, thanks
Member Since: Posts: Comments:
intensely?

The shear isnt that bad in that area
With the new disturbance, this could be similar to Alex of 2004.
Member Since: Posts: Comments:
Quoting Drakoen:
looks to be disorganizing structurally wise, its getting sheared intensely, though.
Member Since: Posts: Comments:


Member Since: Posts: Comments:
Quoting futuremet:


Yes, and today the center is not as exposed.


Yup,

It is certainly under the convection. But looking at Visible Satellite Imagery, I see an Outflow Boundary moving out of the convection on the NW side. Which can mean two thing's, either 1.) The surface circulation is very small, or 2.) The Surface Circulation dissipated and whatever circulation it has it is at the Mid-Level's.

IMO, Scenario 1 is the most likely solution simply because it has decent Vorticity on radar.
Member Since: Posts: Comments:
I like it IKE... No worries so far... Now if this pattern could hold through to say December 1 - that would be even nicer.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting Drakoen:
97L does not have a closed low. There is evidence that the Bahamas disturbance is trying to get better organized with an 850mb vorticity maxima over the southern Bahamas with increased lower level convergence. You can see a spin just north of Cuba.


yea I noticed that too
Looks more Like March on that one IKE.
Member Since: Posts: Comments:
Quoting PalmBeachWeatherBoy:
TRAVELING TO SANTO DOMINGO, DOMINICAN REPUBLIC TOMORROW!!

my flight is in the afternoon tomorrow and i see 97L is gonna make it very windy and rainy there. is their a chance my flight might get delayed or will the storm have passed? should i expect turbulence on the flight when we approach?


check with your airline
Quoting centex:
97L COC not going to PR. Use radar for tracking center.Link

Looks like a relocating center?
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:


headed right for DR and Haiti, based on the track it will stay over land for a long time = SPLAT lol
i think its gonna enter through Santo Domingo and go out through Mole Saint-Nicholas.
Member Since: Posts: Comments:
97L does not have a closed low. There is evidence that the Bahamas disturbance is trying to get better organized with an 850mb vorticity maxima over the southern Bahamas with increased lower level convergence. You can see a spin just north of Cuba.
Member Since: Posts: Comments:
splat for 97L I mean, could be a bad scenerio for Hispanoila

Viewing: 307 - 257

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 | 38Blog 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.

JeffMasters's Recent Photos

Carrot Nose in Danger
Deep Snow in Brookline, MA
Sunset at Fort DeSoto
New Years Day Sunset in Death Valley