Tropical Storm Don forms in the Gulf of Mexico

By: Dr. Jeff Masters , 9:29 PM GMT on July 27, 2011

Share this Blog
8
+

Tropical Storm Don, the fourth tropical cyclone of the 2011 season, has formed in the Gulf of Mexico just north of the Yucatan Peninsula. Hurricane Hunters began investigating the system earlier this afternoon and quickly found a closed surface circulation. As the mission continued to gather data from what was thought to be a tropical depression at the time, winds of around 39 mph were found, as well as a 1001 mb central pressure, bringing the system up to tropical storm strength.


Figure 1. Satellite loop of Tropical Storm Don. This loop will stay current.

The official forecast for Don agrees with what most of the models have been suggesting over the past 24 hours. Don will make its way toward the northwest over the next 48 hours before making landfall somewhere between Brownsville and Galveston. The statistical models tend to suggest a more southerly track toward Brownsville, and the dynamical models are forecasting anything from Corpus Christi to Galveston. They all tend to agree landfall will occur late on the 29th (Friday night). Whether or not Don will reach hurricane status is still in question. The Hurricane Center's initial forecast is that Don will remain a tropical storm until landfall. Today some models were intensifying Don to a strong tropical storm, but none crossed the hurricane threshold. Now that we have data from aircraft reconnaissance, the models will be able to get a better handle on potential intensity. The runs that occur later tonight and early tomorrow will have much less uncertainty than those from today.


Figure 2. Model forecast tracks for Tropical Storm Don as of Wednesday afternoon.

I believe Jeff will be back tomorrow for an update.

Angela

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: 526 - 476

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 | 35Blog Index






18Z Don Cyclone Models
Member Since: Posts: Comments:
Is it true that the storm is now moving northwest instead of wnw?
Member Since: Posts: Comments:
Quoting Grothar:


Sorry it took so long to respond. I don't know how to answer a response in which you agree with me. I was taken a little aback. Are you OK?
A little under the weather, sorry to have given you such a shock. Your ticker handle it okay?
Member Since: Posts: Comments:
521. DFWjc
Quoting gulfbreeze:
Texas needs the rain but as dry as it's been the ground is hard as rock. I lived in Auston 1983-85 and to much rain will cause some major Flash Floods!!


Alicia did a number to Texas in '83
Member Since: Posts: Comments:
Really, how many major Hurricanes have hit before the middle of August? What are the stats?
Member Since: Posts: Comments:
Convection is exploding in the bands once again:

Member Since: Posts: Comments:
Texas needs the rain but as dry as it's been the ground is hard as rock. I lived in Auston 1983-85 and to much rain will cause some major Flash Floods!!
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
needs a little more time sun just gone down if convective refire fails to init then we may have a weaker system but iam expecting convective refire to commence by 11 pm est and expand and dev further at that time as well


agree Keep...i said earlier that it would be hoppin by 5pm tomorrow...more than what the models are calling for IMO...no...i am not an expert...but gut feeling on this one says it is gonna do everything they DONT expect it to...
Member Since: Posts: Comments:
I'm going to throw out a top of my head guess that by landfall if everything stays about the same Don will be a Min. Cat.1 and at max a lower end Cat. 2 by landfall somewhere near Rockport, TX or Aransas Pass, TX. To me the idea of a tropical storm with conditions that they are now is kind of silly.
Member Since: July 25, 2011 Posts: 0 Comments: 453
Quoting atmoaggie:
That it does.


Sorry it took so long to respond. I don't know how to answer a response in which you agree with me. I was taken a little aback. Are you OK?
Member Since: Posts: Comments:
Mid level steering says TX...somewhere.
*shrug*


(full size...click)
Member Since: Posts: Comments:
Quoting Grothar:
Don doesn't look so good right now, but as we all know that doesn't mean much in a developing system. It seems to have a little better outflowto the NW, but as Levi alluded to before, it is getting a little crunched in the Northeast. It appears it will try to wrap a little moisture from the Northeast which is beginning to move down.

needs a little more time sun just gone down if convective refire fails to init then we may have a weaker system but iam expecting convective refire to commence by 11 pm est and expand and dev further at that time as well
Member Since: July 15, 2006 Posts: 170 Comments: 53462
Quoting amd:


also, I think Don is still over the shelf water off the northern coast of the Yucatan which is the location of the coolest water in the Gulf of Mexico. D-Min plus shelf water = slightly more ragged looking system on IR. IMHO, strengthening of Don may not occur until it gets above 23 North. After that however, I also concur of eventual strengthening to a cat 1 just before landfall.


Agreed!!
Member Since: Posts: Comments:
www.rifleman.org.uk/MSLP
Member Since: July 3, 2005 Posts: 423 Comments: 127803
Quoting GHOSTY1:
Don't most developing tropical systems periodically shed some of its thunderstorms and replace them while its in the process of intensification or am i just thinking i heard this?
It could be. But in this case it's more due to dry air intruding into the system causing for downdrafts. (After a downdraft crashes onto the surface, they expand outwards, and those were the arc clouds that you saw on visible a little earlier).

The diurnal minimum also isn't helping the situation.
Member Since: September 2, 2009 Posts: 130 Comments: 21098
Quoting caneswatch:


I'm surprised they're not mentioning the wave at 30W.


Still early days yet. There is a 1008mb low along the wave axis but little thunderstorm activity at the moment. Great cyclonic turning though, and it shows up nicely on the vorticity maps. This should be watched, especially when after it moves a bit farther west.
Member Since: Posts: Comments:
I'm thinking by morning and recon data feed into models, NHC will start predicting Cat 1 at landfall. Hard to believe it would be first Hurricane landfall since Ike 2008.
Member Since: Posts: Comments:
Quoting stormpetrol:


True , but I always said I thought 90L would develop! Don is not in a great location right now, instead of having the high to ventilate him, he has it somewhat crushing him, at least that what's my untrained eye is seeing, but he's a bad boy, got to watch him :)


I know you have. But haven't you been reading my blogs? You should see them.
Member Since: Posts: Comments:
Plan for the evening:

1) Don looses convection near it's COC.
2) People begin RIPing Don.
4) Circulation reforms
3) By Dawn Donnie Boy is a force to be reckoned with.
Member Since: Posts: Comments:
If if continues to follow the NHC forecast i should be in Corpus Christi the same time it makes it there so i should get a first hand account of how strong or weak the storm or maybe hurricane Don is.
Member Since: July 25, 2011 Posts: 0 Comments: 453
My amateur opinion says landfall along the central to west Louisiana Coast. Just a gut feeling...
Member Since: Posts: Comments:
back from school shopping and buying gas before the prices go up...not too bad of a trip...got $28 worth of school stuff for $6.43 after coupons, vouchers n rebates and just got a little over 16 gallons of gas for $29 using my points from the grocery store... YAY...
Member Since: Posts: Comments:
am going too send DON a $5000 bill be come i help it heel by saying RIP and it better pay up
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:


I expect Don to have intensifies to 50-60 mph when I wake up.


That's better.
Member Since: Posts: Comments:
Quoting sarahjola:
maybe southeast louisiana, but west louisiana still needs to pay attention. i have been seeing for a while now that don is moving nw. now i see that hh are saying the same. not to say it won't go back to wnw but every move to the nw puts landfall a little further east than projected.
I've been seeing that also and I thought that was a jog.
Member Since: Posts: Comments:
Quoting Grothar:


Then why do you expect a 50 or 60 mph TS when you wake up?


I expect Don to have intensified to 50-60 mph when I wake up.
Member Since: Posts: Comments:
hey guys seem that I have missed a lot between Mon and now I see that 90L became Don or is it 91L and seems we may get another with that low in the E/central atl and maybe another with that tropical wave in the e carib and surface trough so can all of you guys give me a proper sitrep on what in the world is going on in the tropics
Member Since: Posts: Comments:
Quoting jrweatherman:


You must live in the Houston/Galveston area or Louisiana.


Thats a negitive....

I Live in Mobile AL

\Taco :o)
Member Since: July 7, 2005 Posts: 6 Comments: 3247
Quoting Grothar:
Don doesn't look so good right now, but as we all know that doesn't mean much in a developing system. It seems to have a little better outflowto the NW, but as Levi alluded to before, it is getting a little crunched in the Northeast. It appears it will try to wrap a little moisture from the Northeast which is beginning to move down.



True , but I always said I thought 90L would develop! Don is not in a great location right now, instead of having the high to ventilate him, he has it somewhat crushing him, at least that what's my untrained eye is seeing, but he's a bad boy, got to watch him :)
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:


I don't.


Then why do you expect a 50 or 60 mph TS when you wake up?
Member Since: Posts: Comments:
....earlier,

18z Early Cycle NHC model tracks
Don
Statistical/Simple Models (CLIPER,BAMs,LBAR,other Statistical Models)




Dynamic Models (More sophisticated models)




Member Since: July 3, 2005 Posts: 423 Comments: 127803
I see a front pulling it North. The stronger Don gets, the more North it will go. It's a general rule that a weaker storm heads more to the West, and a stronger storm heads more to the North. I expect a landfall between Houston and Morgan City, with it most likely occurring somewhere around Port Arthur.
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT WED JUL 27 2011

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

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON NEWLY FORMED
TROPICAL STORM DON LOCATED ABOUT 755 MILES EAST-SOUTHEAST OF CORPUS
CHRISTI TEXAS.

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

PUBLIC ADVISORIES ON TROPICAL STORM DON ARE ISSUED UNDER WMO HEADER
WTNT34 KNHC AND UNDER AWIPS HEADER MIATCPAT4. FORECAST/ADVISORIES
ARE ISSUED UNDER WMO HEADER WTNT24 KNHC AND UNDER AWIPS HEADER
MIATCMAT4.

$$
FORECASTER AVILA


I'm surprised they're not mentioning the wave at 30W.
Member Since: Posts: Comments:
Quoting BiloxiGirl:
Is it safe to say that Louisiana and east are in the clear with regards to Don?
maybe southeast louisiana, but west louisiana still needs to pay attention. i have been seeing for a while now that don is moving nw. now i see that hh are saying the same. not to say it won't go back to wnw but every move to the nw puts landfall a little further east than projected.
Member Since: September 10, 2008 Posts: 0 Comments: 1293
Quoting GHOSTY1:
Don't most developing tropical systems periodically shed some of its thunderstorms and replace them while its in the process of intensification or am i just thinking i heard this?


You are correct.
Member Since: Posts: Comments:
Quoting Patrap:
The MSLP is interesting


So, can you elaborate?
Member Since: July 16, 2007 Posts: 0 Comments: 86
Don't most developing tropical systems periodically shed some of its thunderstorms and replace them while its in the process of intensification or am i just thinking i heard this?
Member Since: July 25, 2011 Posts: 0 Comments: 453
482. amd
Quoting tennisgirl08:


Looks like Don is getting smushed via its northern side. Whatever is causing this is also causing it to slow down. I'm thinking Don is looking a little more ragged now, but once it starts moving again it will move further west and gain more strength.


also, I think Don is still over the shelf water off the northern coast of the Yucatan which is the location of the coolest water in the Gulf of Mexico. D-Min plus shelf water = slightly more ragged looking system on IR. IMHO, strengthening of Don may not occur until it gets above 23 North. After that however, I also concur of eventual strengthening to a cat 1 just before landfall.
Member Since: Posts: Comments:
Quoting Tazmanian:



good luck with that am forcasting 70 too 90mph storm when i wake up


Well your going to be disappointed.
Member Since: Posts: Comments:
Quoting JLPR2:


If July ends with 4named storms I'll need a new jaw. XD
well i guess a new jaw it will be
Member Since: July 15, 2006 Posts: 170 Comments: 53462
Quoting Grothar:


I didn't know you lived in Texas?


I don't.
Member Since: Posts: Comments:
Quoting Grothar:
Don doesn't look so good right now, but as we all know that doesn't mean much in a developing system. It seems to have a little better outflowto the NW, but as Levi alluded to before, it is getting a little crunched in the Northeast. It appears it will try to wrap a little moisture from the Northeast which is beginning to move down.

That it does.
Member Since: Posts: Comments:
Quoting GHOSTY1:
Even with Don slowing down to 9mph what do you think the chances of any direct impacts on Houston would be? (percentages preferablly)


I'm no met, but I'd say 50-50 chance.
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:
Mid-level circulation still a little bit dis-coupled with the low-level one, but they will be together very shortly. Once this happens, expect modest strengthening. I'm expecting a 50-60 mph tropical storm when I wake up tomorrow morning.


I didn't know you lived in Texas?
Member Since: Posts: Comments:

Viewing: 526 - 476

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 | 35Blog 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
71 °F
Overcast