Gaston still a threat to redevelop

By: Dr. Jeff Masters , 3:17 PM GMT on September 05, 2010

Share this Blog
3
+

For the first time since August 22, when Danielle became a tropical storm, there are no named storms active in the Atlantic. An extratropical storm absorbed Tropical Storm Earl last night, bringing an end to the 11-day life of the 2010 season's longest-lived storm. While Earl was mostly a non-event for North Carolina and New England, the storm gave Nova Scotia a solid pounding, reminding us of what could have easily happened to New England had the forecast track deviated slightly to the left. Kudos go to the computer models and NHC, who successfully predicted the path of Earl very accurately four days in advance. As we approach the climatological peak of Atlantic hurricane season, which occurs on September 10, there are no indications that today's break in the action represents a beginning of an extended quiet period in the Atlantic. Indeed, we have two systems that could become tropical depressions in the next day, and we also have model predictions of another storm to come late in the week.


Figure 1. Morning satellite image of the remains of Gaston, approaching the Lesser Antilles Islands.

Gaston near tropical depression status again
The remains of Tropical Storm Gaston, located about 700 miles east of the Lesser Antilles Islands and moving west at about 13 mph, are close to reaching tropical depression status again. Recent satellite imagery shows that Gaston's remains have developed a well-organized surface circulation, but not enough heavy thunderstorm activity to be considered a tropical depression. A large amount of dry air surrounds Gaston's remains on all sides, as seen on water vapor satellite loops. This dry air will continue to be a major impediment to development. The latest SHIPS model forecast predicts shear will remain moderate, 10 - 15 knots, for the next three days, then fall to the low range. The winds creating the shear are coming from the east, where a tongue of dry air has intruded. These easterly winds will be able to drive the dry air into Gaston's core, disrupting it, unless the storm can find a moister environment, or moisten its environment on its own by generating enough heavy thunderstorms. Gaston has managed to develop more heavy thunderstorms near its center of circulation late this morning, but the amount of dry air it is battling is formidable. Even if Gaston does manage to become a tropical depression today, development will be slow over the next few days, due to the dry air. When Gaston passes over or just to the northeast of the Lesser Antilles Islands early Tuesday morning, the storm is unlikely to have more than 50 mph winds. More significant development is possible later in the week, as the atmosphere should be moister for Gaston. Gaston may threaten Puerto Rico on Wednesday, the Dominican Republic on Thursday, and Haiti, Jamaica, and/or the Turks and Caicos Islands by Friday, depending upon the storm's interaction with a trough of low pressure expected to move off the U.S. East Coast later this week. The earlier Gaston develops into a tropical storm, the more likely it is to "feel" the upper-level winds of the approaching trough, and curve more to the northwest. The HWRF model predicts Gaston will develop by Monday, and pass just northeast of the Lesser Antilles Islands Tuesday morning. The GFDL model, on the other hand, delays development until Wednesday, keeping Gaston in the Caribbean. The GFDL has Gaston hitting Jamaica as a strong tropical storm on Friday morning. However, the GFDL forecast is dubious, because on Wednesday and Thursday, Gaston may have an encounter with the high mountains of the island shared by the Dominican Republic and Haiti, Hispaniola, which could easily destroy a system as fragile as Gaston. Gaston has a 70% chance of developing into a tropical depression by Tuesday, according to NHC.

Gulf of Mexico disturbance 90L
A concentrated area of heavy thunderstorms (90L) has developed over the extreme southwestern Gulf of Mexico, in the Bay of Campeche. Satellite imagery shows that this disturbance is disorganized, but has some modest spin to it. The disturbance is under a moderate 10 - 15 knots of wind shear, and has a 60% chance of developing into a tropical depression by Tuesday, according to NHC. The disturbance is headed northwest at 5 - 10 mph, and should bring heavy rains to the Texas/Mexico border region on Monday, according to the latest run of the GFS model. The main impediment to development will be the limited time 90L has over water; the storm will be ashore by Tuesday, which doesn't give it much time to develop.

Elsewhere in the tropics
The GFS and NOGAPS models are predicting development on Thursday of a tropical wave that will emerge from the coast of Africa on Tuesday or Wednesday.

Next post
I'll have an update Monday morning.

Jeff Masters

Sunrise Surf was cranking (RIWXPhoto)
Sunrise Surf was cranking
Post Hurricane Earl surf photos at Newport, RI (RIWXPhoto)
Post Hurricane Earl surf photos at Newport, RI

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: 235 - 185

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 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59Blog Index

Quoting MiamiHurricanes09:
The HPC has ex-Gaston just north of HispaƱiola in 7 days:


Do you think it is really gonna take 7 days to get to Hispaniola? Cause I say 5 based on those fast trades in the caribbean, unless steering currents collapse. Right now I notice an ULL over Puerto Rico & Hispaniola.
Member Since: Posts: Comments:
I'm out for the afternoon, work to be done...

before I go, look at the moisturizing and convecting on the east side of Gaston, he is making his attempt at rebirth...

NOAA Visible
Member Since: Posts: Comments:
Quoting Goldenblack:
Oh no you did not just give us the "NAM" did you?

lol



NAM= Not a Model lol
Member Since: Posts: Comments:
Good Afternoon! :)
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting TOMSEFLA:
i guess we all miss levi video updates.maybe someone can twist his arm and get him back at least when needed...............
Leave the young man alone. He has his priorities straight. Hope he discovers girls and disappears for a bit.
Member Since: Posts: Comments:
Quoting Vero1:


Not sure but someone is drawing charts that indicate:



Galveston, Oh Galveston.
Member Since: Posts: Comments:
Maybe Gas man just wants some Rum? Good place to go...

Quoting stormwatcherCI:

If this follows what the NHC says it looks to come right about over the Jamaica and the Cayman Islands and NO I am not a wishcaster, just a realist.
Member Since: Posts: Comments:
227. Vero1
Member Since: Posts: Comments:
From the THE HYDROMETEOROLOGICAL PREDICTION CENTER (HPC) EXTENDED FORECAST DISCUSSION:

EASTWARD REMANTS OF TS GASTON REGENERATING AND CARRIED WESTWARD BY
FAIRLY WELL AGREED UPON MODEL GUIDANCE AND HPC/NHC COORDINATION
INTO THE LESSER ANTILLES BY TUESDAY AND REACHING THE EASTERN
GREATER ANTILLES BY FRIDAY AND SATURDAY. SEE NHC DISCUSSIONS AND
FUTURE ADVISORIES.
ROSENSTEIN
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Quoting GTcooliebai:

I say it continues West, and I betcha I'm right!

Only time will tell and maybe you will be right. I give you about 40%.
Member Since: Posts: Comments:
Quoting Neapolitan:


"Diminshing" is a subjective term. While it's less and less likely to happen, the standard Cape Verde season runs through August and September, though CV-type storms in October aren't at all rare.

I'd also like to remind folks that "home-grown" types can be pretty vicious. Rita, Wilma, Ivan, Camille, Katrina, 1935 Labor Day Storm...none of these were CV-type storms. So, you know, don't breathe quite so easy just yet... ;-)
Which Ivan you talking about ? Ivan 2004 was a CV storm.
Member Since: Posts: Comments:
Quoting Neapolitan:


"Diminshing" is a subjective term. While it's less and less likely to happen, the standard Cape Verde season runs through August and September, though CV-type storms in October aren't at all rare.

I'd also like to remind folks that "home-grown" types can be pretty vicious. Rita, Wilma, Ivan, Camille, Katrina, 1935 Labor Day Storm...none of these were CV-type storms. So, you know, don't breathe quite so easy just yet... ;-)

Well said
Member Since: Posts: Comments:
The HPC has ex-Gaston just north of HispaƱiola in 7 days:

Member Since: September 2, 2009 Posts: 130 Comments: 21091
A few frames back I posted the 400-850mb steering layers...which I can post again if necessary. If Gaston continues its current attempt at re-organization, there is no way he gets that far south.....if he waits another day or two, or stays really really weak (depression or weak TS) then that can happen...

Quoting stormwatcherCI:
.SYNOPSIS AND FORECAST.

.ATLC REMNANT LOW PRES OF GASTON 17N49W 1009 MB. WITHIN 360 NM N
SEMICIRLCE AND 120 NM SE QUADRANT WINDS 20 TO 25 KT. SEAS TO 10
FT.
.24 HOUR FORECAST LOW PRES...POSSIBLE TROPICAL CYCLONE...NEAR
17N55W 1008 MB. WITHIN 360 NM NE AND 90 NM SW SEMICIRCLES WINDS
20 TO 25 KT. SEAS TO 11 FT.
.48 HOUR FORECAST LOW PRES...POSSIBLE TROPICAL CYCLONE...NEAR
17.5N62W 1008 MB. WITHIN 360 NM N SEMICIRCLE WINDS 20 TO 30 KT.
SEAS 8 TO 12 FT. WITHIN 90 NM S SEMICIRCLE WINDS 20 KT. SEAS TO
8 FT.
If this follows what the NHC says it looks to come right about over the Jamaica and the Cayman Islands and NO I am not a wishcaster, just a realist.
Member Since: Posts: Comments:
Quoting Vero1:


Not sure but someone is drawing charts that indicate:



hmmmm, that is interesting....by that it looks to go a little more north.
Member Since: Posts: Comments:
Quoting BDADUDE:

It will start to feel the weakness by day 2 or 3.

I say it continues West, and I betcha I'm right!
Member Since: Posts: Comments:
Quoting TropicalBruce:
Except for the possibility of "Gaston" doing so, the chances of any Cape Verde storms reaching the U.S. is diminishing day by day as the fall season approaches and the troughs from Canada into the eastern U.S. continue to gradually get stronger. U.S. threats are going to be limited to home grown products as well as storms which form in the Caribbean/Gulf.


"Diminshing" is a subjective term. While it's less and less likely to happen, the standard Cape Verde season runs through August and September, though CV-type storms in October aren't at all rare.

I'd also like to remind folks that "home-grown" types can be pretty vicious. Rita, Wilma, Ivan, Camille, Katrina, 1935 Labor Day Storm...none of these were CV-type storms. So, you know, don't breathe quite so easy just yet... ;-)
Member Since: November 8, 2009 Posts: 4 Comments: 13461
216. Vero1
Quoting TexasHurricane:
So is 90L going into MX or S.TX?


Not sure but someone is drawing charts that indicate:

Member Since: Posts: Comments:
Quoting TexasHurricane:
So is 90L going into MX or S.TX?
Most likely that the circulation will make a final landfall over northern Mexico, however, heavy rainfall from the system will be felt across southern Texas.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
i guess we all miss levi video updates.maybe someone can twist his arm and get him back at least when needed...............
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Should begin to move back towards the west since it is still being steered by the low level easterly flow of the subtropical ridge to the north. I assume that the northward wobble was just because the circulation naturally wants to be under the convection.
.SYNOPSIS AND FORECAST.

.ATLC REMNANT LOW PRES OF GASTON 17N49W 1009 MB. WITHIN 360 NM N
SEMICIRLCE AND 120 NM SE QUADRANT WINDS 20 TO 25 KT. SEAS TO 10
FT.
.24 HOUR FORECAST LOW PRES...POSSIBLE TROPICAL CYCLONE...NEAR
17N55W 1008 MB. WITHIN 360 NM NE AND 90 NM SW SEMICIRCLES WINDS
20 TO 25 KT. SEAS TO 11 FT.
.48 HOUR FORECAST LOW PRES...POSSIBLE TROPICAL CYCLONE...NEAR
17.5N62W 1008 MB. WITHIN 360 NM N SEMICIRCLE WINDS 20 TO 30 KT.
SEAS 8 TO 12 FT. WITHIN 90 NM S SEMICIRCLE WINDS 20 KT. SEAS TO
8 FT.
If this follows what the NHC says it looks to come right about over Jamaica and the Cayman Islands and NO I am not a wishcaster, just a realist.
Member Since: Posts: Comments:
Kinda looks like it is going to be felt with at least moisture over a wide area....at least right now.

Quoting TexasHurricane:
So is 90L going into MX or S.TX?
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Should begin to move back towards the west since it is still being steered by the low level easterly flow of the subtropical ridge to the north. I assume that the northward wobble was just because the circulation naturally wants to be under the convection.

It will start to feel the weakness by day 2 or 3.
Member Since: Posts: Comments:
So is 90L going into MX or S.TX?
Member Since: Posts: Comments:
Orca, we surmised that they are "on vacation" so to speak...lol

Quoting Orcasystems:
Updated... Gaston's intensity numbers have gone down... but it looks healthier? Go figure?



AOI

AOI

AOI

AOI

AOI

AOI


TS BUSTED FORECAST ALIBI
Member Since: Posts: Comments:
Quoting TropicalBruce:
Except for the possibility of "Gaston" doing so, the chances of any Cape Verde storms reaching the U.S. is diminishing day by day as the fall season approaches and the troughs from Canada into the eastern U.S. continue to gradually get stronger. U.S. threats are going to be limited to home grown products as well as storms which form in the Caribbean/Gulf.


Can you show this or are you basing on this on climatology? Thank you in advance.
Member Since: Posts: Comments:
Agreed, I am not trying to take sides....just looking strictly at the visible where the center has been fairly easy to track until just the past few frames..

Quoting MiamiHurricanes09:
Should begin to move back towards the west since it is still being steered by the low level easterly flow of the subtropical ridge to the north. I assume that the northward wobble was just because the circulation naturally wants to be under the convection.
Member Since: Posts: Comments:
gaston the survival coming soon on land near you,impressive system considering the dry air that have benn affecting the system for his entire life, now that is what i call extreme survival,lolLink
Member Since: Posts: Comments:
Updated... Gaston's intensity numbers have gone down... but it looks healthier? Go figure?



AOI

AOI

AOI

AOI

AOI

AOI


TS BUSTED FORECAST ALIBI
Member Since: October 1, 2007 Posts: 81 Comments: 26511
204. JeffM
Quoting Bordonaro:
NAM 54 HRS has a weak TS making landfall on the lower TX coast



While the people in deep South Texas probably don't need more rain, we up in in South/Central TX need it bad!
Member Since: Posts: Comments:
Quoting Goldenblack:
Sorry to interject all..

The center is moving just a very little hair north of due west....and is where MH09 says...17.1

Should begin to move back towards the west since it is still being steered by the low level easterly flow of the subtropical ridge to the north. I assume that the northward wobble was just because the circulation naturally wants to be under the convection.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
201. code1
While some may seem "unaware", I fail to see where many coastal residents are, unless new residents. Hey, there's a new (from '06) dance in town for all coastal areas. We wish these storms to go "to the right, to the right, to the right, to the right, to the left, to the left..."
Hope all ease the meat of season just fine! Happy Labor Day!!!
Cupid Shuffle instruction for us old folk
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Go to this loop, zoom in near 17N or so and speed it all the way up. Notice how the circulation was near 16.9N when it was exposed and then it took a slight jog towards the north to advect under the convective canopy. Looks to even be near 17.1N now. The key on determining where it is, is the lower level inflow and banding.

I see what you are saying but it still looks more to me like it is pulling the moisture over it more than the center moving more north but IDK
Member Since: Posts: Comments:
Quoting Neapolitan:


Based on what, exactly? We may be close to the climatological "peak" of the season, but based on all indicators, we're barely a third of the way through.

My seasonal forecast hasn't changed since July: 20/12/6/180.(Yes, that means 13/9/4/118 to go. We'll get there, I think, or pretty darn close.)


imo we'll peak at sep20-oct1 but all oct will be as active as peak so we can have 20/12/6/180 but i give numbers: 19/11/6/190
Member Since: Posts: Comments:
To me it looks like the entire envelope of 90l is moving more west than north, judging by the vis sat.
Member Since: Posts: Comments:
Sorry to interject all..

The center is moving just a very little hair north of due west....and is where MH09 says...17.1

Quoting MiamiHurricanes09:
Go to this loop, zoom in near 17N or so and speed it all the way up. Notice how the circulation was near 16.9N when it was exposed and then it took a slight jog towards the north to advect under the convective canopy. Looks to even be near 17.1N now. The key on determining where it is, is the lower level inflow and banding.

Member Since: Posts: Comments:
Quoting Kristina40:


Panicky? Should I be happy all these storms are popping up?


Yes, Panicky. "A sudden overwhelming fear of clouds over Africa"

Seems like a normal hurricane season to me so far.
Member Since: Posts: Comments:
90L is moving NNW and is now at 19.8N and 95.6W. It must be a depression by now.
Member Since: Posts: Comments:
Quoting Goldenblack:
Why thank you Orca!



Its one of my AOI's
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting TheDawnAwakening:
MH09, so the 12z GFS develops both waves?
I don't think so. Maybe PGI41L absorbs PGI42L while it is still overland since it is the dominant feature. I do believe that the GFS does develop PGI41L...pretty much dissipates PGI42L.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Why thank you Orca!

Quoting Orcasystems:


Member Since: Posts: Comments:
190. Vero1




Member Since: Posts: Comments:
Quoting Neapolitan:


Based on what, exactly? We may be close to the climatological "peak" of the season, but based on all indicators, we're barely a third of the way through.

My seasonal forecast hasn't changed since July: 20/12/6/180.(Yes, that means 13/9/4/118 to go. We'll get there, I think, or pretty darn close.)


Let me rephrase that. I HOPE this will be the peak.
Member Since: Posts: Comments:
Quoting Goldenblack:
The Tampa..."blobby thingy" is getting bigger....coming to rain on our labor parade...

Radar Loop


Member Since: October 1, 2007 Posts: 81 Comments: 26511
Gas man is saying "hey, looky what environment I found.....I like it here"

Quoting stormwatcherCI:


Wrapping up pretty good.
Member Since: Posts: Comments:
Quoting stormwatcherCI:
I know that you know more than me but I don't think it is at 17N yet either. Looks more like it is just pulling the convection over it like a blanket.
Go to this loop, zoom in near 17N or so and speed it all the way up. Notice how the circulation was near 16.9N when it was exposed and then it took a slight jog towards the north to advect under the convective canopy. Looks to even be near 17.1N now. The key on determining where it is, is the lower level inflow and banding.

Member Since: September 2, 2009 Posts: 130 Comments: 21091

Viewing: 235 - 185

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 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59Blog 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.

Local Weather

Overcast
62 °F
Overcast