Don closing in on Texas; 91L a potential threat to the Lesser Antilles

By: Dr. Jeff Masters , 3:22 PM GMT on July 29, 2011

Share this Blog
10
+

Tropical storm warnings are flying along the coast of Texas from Brownsville to Matagorda as Tropical Storm Don closes in on the Texas coast. Don remains a disorganized, moderate strength tropical storm, and appears unlikely to cause major damage or bring much-needed drought-busting rains to Texas. A hurricane hunter plane is in Don, and found highest surface winds of 55 mph at 11:06am EDT. Don continues to have trouble with moderate wind shear of 10 - 20 knots, which is injecting dry air to the northwest into the storm. Water vapor satellite images show this region of dry air to the northwest of Don. Visible satellite imagery from this morning shows little change to Don so far today, with most of the heavy thunderstorms on Don's south side, and the cloud pattern elongated, the sign of a storm struggling with wind shear. Radar out of Brownsville, Texas shows the main rain areas are on the south of Don's center, and bands of heavy rain are now very close to the Texas/Mexico border.


Figure 1. Morning image of Tropical Storm Don from the Brownsville, Texas radar.


Figure 2. The latest drought map for Texas shows that over 75% of the state is in exceptional drought--the highest category of drought. Image credit: U.S. Drought Monitor.

Forecast for Don
The wind shear and dry air affecting Don will continue until landfall, and it is unlikely Don will intensify to more than a 60 mph tropical storm. With most of the heavy thunderstorms displaced to the south side of the storm, Mexico will be the primary beneficiary of Don's expected rains of 3 - 5 inches. South Texas will see modest rains of 1 - 2 inches over a few isolated areas, but Don is going to do very little to bring drought relief to the state. Most of Don's rains in Texas will be concentrated in the extreme southern portion of the state near Brownsville. This portion of Texas is experiencing only moderate drought, and the extreme to exceptional drought areas of the state will miss the bulk of Don's rains.

For those of you wondering about your odds of experiencing tropical storm force winds, I recommend NHC's wind probability forecast. The 11 am version of this forecast shows that Corpus Christi Texas has the highest chance of tropical storm-force winds (39+ mph): 48%. The primary threat from Don will be heavy rain, which will caused localized flooding problems. An isolated tornado is also a possible concern.


Figure 3. Morning satellite image of 91L.

African wave 91L a potential threat to the Lesser Antilles
A well-organized African wave near 9°N 44°W (Invest 91L) is headed west-northwest at 15 - 20 mph, and could arrive in the vicinity of the Lesser Antilles Islands as early as Monday night. Residents of the Lesser Antilles should pay careful attention to this system, as it has the potential to organize into a tropical storm before reaching the islands. While visible satellite loops currently show only minimal heavy thunderstorm activity and no signs of a surface circulation, there is a pronounced large-scale rotation to the cloud pattern. Water vapor satellite loops show that a large area of dry air from Africa lies just to the north of 91L, and this dry air is inhibiting development. The SHIPS model is diagnosing low shear, 5 - 10 knots, over 91L, but the University of Wisconsin CIMSS analysis shows that moderate shear, 10 - 20 knots, is affecting 91L. Sea surface temperatures are 27.5° - 28°C, which is 1° above the 26.5°C threshold usually needed to support a tropical storm.

Forecast for 91L
Low to moderate wind shear of 5 - 15 knots is predicted along 91L's path over the coming three days, which should allow the storm to steadily organize, assuming it can shut out any incursions of dry air that might intrude. The latest 06Z run of the GFS model does show 91L developing into a tropical storm by Monday, but the other three most reliable models for forecasting formation of a tropical storm--the ECMWF, NOGAPS, and UKMET models--show little or no development of 91L in their latest runs. On Monday, when most of the models predict that squalls of rain from 91L will begin affecting the Lesser Antilles, wind shear is expected to rise to the moderate or high range, which should act to interfere with development. The latest runs of the GFDL and HWRF models show 91L developing into a hurricane by Monday, but these models are not to be trusted for systems that have not developed into a tropical depression yet. The long-range path of 91L could take it through the Caribbean or towards the U.S. East Coast; it is too early to know with path might be more probable. NHC is giving a 30% chance that 91L will develop into a tropical depression by Sunday morning.

Iran records its hottest temperature of all-time
Omidieh, Iran and Shoshtar, Iran hit a scorching 52.6°C (126.6°F) on July 27, the hottest temperatures ever recorded in the country. The previous record was 52.5°C (126.5°F) set in Hamidiyeh on August 4, 2001. If confirmed by the Iranian weather service, these readings would rank as the third hottest undisputed temperatures ever measured in Asia. There have been only two Asian readings matching or exceeding Wednesday's new Iranian record of 52.6°C that are undisputed that I am aware of. Both of these occurred last year, and were recognized by their respective country's meteorological services as new official records for their country:

53.5° (128.3°F) in Moenjodaro, Pakistan on May 26, 2010
52.6°C (126.7°F) in Abdaly, Kuwait on June 10, 2010

Iran is the third nation this year to set a new all-time heat record (no nations have set an all-time coldest temperature record this year, or did so in 2010.) The Democratic Republic of the Congo, the world's 12th largest country, set a new all-time extreme heat record on March 8, 2011, when the temperature hit 39.2°C (102.6°F) at M'Pouya. Congo's previous all-time hottest temperature was 39.0°C (102.2°F) at Impfondo on May 14, 2005.

Also this July, a 50.2°C temperature was measured at Aydyngkol Lake, China--the highest temperature on record at any official Chinese weather station. Next week, our weather historian, Christopher C. Burt, will report on this record. Credit for researching these records goes to weather records researcher Maximiliano Herrera, who maintains a comprehensive set of world extreme temperature records on his web site.

Vacation
I'm taking some time off today through August 9 for a family celebration and vacation, and don't plan on blogging again until August 10 unless a major hurricane develops. In my absence, Angela Fritz will be handling most of the blogging duties, and she will have a post on the latest for Don this afternoon. Angela is on Pacific time, so her posts will be later in the day than I make them.

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: 646 - 596

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog Index

645. JLPR2
Quoting stormwatcherCI:
Maybe because the people in the islands are just as much human beings as the ones in the US. PLUS, the islands are WAY smaller than the US with Way less resources than they have so would most likely suffer worse damage.


Including Puerto Rico and the US Virgin Islands that in a way are part of the US. :\

To me a storm that hits land either in Spain, Bermuda, Africa, US, Caribbean in conclusion anywhere were people live is not a fish storm.

Saying a storm is a fish when it killed people in another country makes you wonder what happened to human sympathy.
Member Since: Posts: Comments:
jasonweatherman on that loop you posted with the united states and you can see possible emily coming in to the picture did you see the area that came off louisiana and may have became something then made landfall near CC
Member Since: July 25, 2011 Posts: 0 Comments: 453
Quoting Hurricanejer95:
627
It is a little too harsh to say that, remove it


I dont think so, this is a reality blog
Member Since: Posts: Comments:
Quoting washingtonian115:
I'm (as far as I know)the only person from the city of Washington D.C on here.Well what can I say.At least I don't have to share a state with anyone.D.C is the city everyone looooves to hate.


I live in Arlington. :)
Member Since: Posts: Comments:
Every station that I have turned to including Fox news and Cnn even mentions the wave when their talking about Don.It seems the pros are even worried about this one...
Member Since: Posts: Comments:
Quoting GHOSTY1:


I am a person who also likes to learn about military weaponry and tactics like i like to learn about hurricanes, there are some weapons that produce a large modest explosion without the use of radiation it is called a MOAB uniquelly named for Mother Of All Bombs. The largest non nuclear explosion was produced from this.


Right and those MOAB's have a fraction of the energy of an H bomb which in turn has a fraction of a fraction of the energy of a hurricane.
Member Since: Posts: Comments:
This one here had a strange track. It was supposed to go out to sea a couple times. You never know what they will do. Don't see nothing wrong with discussing the what ifs. That's what we do around here. :)

Member Since: Posts: Comments:
Quoting GHOSTY1:
How many times do i have to say this "No Radiation" once so ever.


Not even a tiny bit? :-)
Member Since: Posts: Comments:
Quoting DFWjc:
CBS 11 Weather
Made it to 100 degrees again at DFW. Streak now at 28 days.

Will the streak ever end???


As soon as the dry spell does, methinks.
Member Since: Posts: Comments:
Quoting Hurricanejer95:
627
It is a little too harsh to say that, remove it


? It's a storm...
Member Since: July 6, 2010 Posts: 113 Comments: 32255
Quoting TropicalAnalystwx13:


Think it could achieve TD status by the end of the month?

LGEM has it at hurricane status in five days...very reliable intensity model.


"Reliable" is not a label I would give to any of our intensity models. We'll see about the end of the month. 54 hours probably isn't enough time for a name, though you never know.
Member Since: Posts: Comments:
627
It is a little too harsh to say that, remove it
Member Since: Posts: Comments:
Fortunate to get rains along upper TX coast, that I am thankful for
Member Since: Posts: Comments:
Quoting ProgressivePulse:



We seem to have missed all those troughs in SFL?



Ya, i'm not sure what troughs he is talking about! Not see that many in Tampa to speak of!
Member Since: Posts: Comments:
I hope you all also notice that the models develop a storm off of the Yucatan the same time they develop invest 91L.
Member Since: Posts: Comments:
Quoting muddertracker:
Radiation-cane? lol...better not..might turn all those florida alligators into godzillas...how would FEMA manage THAT? Is there a policy that covers godzilla attacks?


Don't worry, if there was such a thing as a radiation cane, we wouldn't be having godzillas running around, just a bunch of rotting bodies and deformed/dying things. Unlike the movies, radiation in real life kills, and those that survive it look like they have caught a terrible disease.

Radiation in real life is actually scarier, if you ask me.
Member Since: Posts: Comments:
Look at all those clear skies in the gulf behind Don, gonna cook and burn up tomm and into next week
Member Since: Posts: Comments:
Don was a stupid system from the beginning, couldn't hack it
Member Since: Posts: Comments:
Quoting tiggeriffic:


gee...thanks, i feel the love...lol, i live in SC... my oldest son moved back here from DC a little more than a year ago...
I'm (as far as I know)the only person from the city of Washington D.C on here.Well what can I say.At least I don't have to share a state with anyone.D.C is the city everyone looooves to hate.
Member Since: Posts: Comments:
Quoting yonzabam:


You know, I'm sick of hearing about this continual bickering about what constitutes a 'fish storm'.

If it recurves out to sea and knocks a chimney pot down in Ireland do we not call it a 'fish storm'?

If it causes some damage as a tropical storm in the Antilles, but recurves before it hits a continental land mass as a hurricane, it's understandable that people living in the US would call that a 'fish storm'. Personally, I don't have a problem with that, but some folk seem to have a need to appear as more caring human beings and be seen to be more sympathetic towards those islanders. I wonder why that is.

Maybe because the people in the islands are just as much human beings as the ones in the US. PLUS, the islands are WAY smaller than the US with Way less resources than they have so would most likely suffer worse damage.
Member Since: Posts: Comments:
How many times do i have to say this "No Radiation" once so ever.
Member Since: July 25, 2011 Posts: 0 Comments: 453
Quoting yoboi:



fish storm


Point proven.

Also, I do hope you know what "boi" means?
Member Since: Posts: Comments:
621. DFWjc
Quoting TropicalAnalystwx13:


Do you watch FOX4 or WFAA8?


N-O! I don't like political commentary with my weather, LOL :P
Member Since: Posts: Comments:
Quoting Levi32:
Invest 91L has a long way to go yet. It's a massive circulation with multiple vortices which will take time to consolidate. Dry air is also an issue. However, gradual development is likely as it approaches the northeastern Caribbean, and I do have a feeling we will get Emily out of this at some point in that area.


Think it could achieve TD status by the end of the month?

LGEM has it at hurricane status in five days...very reliable intensity model.
Member Since: July 6, 2010 Posts: 113 Comments: 32255
Quoting RitaEvac:
Central TX your not gonna get a drop from Don

Yup. Maybe a passing shower..kinda sad.
Member Since: Posts: Comments:
Quoting MrstormX:
Why are we already plotting 91Ls path to the United States it seems a little premature.


Why does the NHC post the model graphics then!?????
Member Since: Posts: Comments:
Quoting Jedkins01:
Now keep in mind, we are talking long term here, but a strong trough is expected to dig down to the Gulf Coast/Florida next week. That has been a common pattern this year. That being said as it stands now 91L doesn't appear to be a much threat to Florida. But it is very long term so we will watch the system and watch to see how things develop. Also, people need to get a hold of them selves and be more patient, I'm hearing way too much talk about major hurricanes when we have a freaking invest on our hands lol. Give it time.



We seem to have missed all those troughs in SFL?
Member Since: August 19, 2005 Posts: 5 Comments: 5449
616. DFWjc
Quoting RitaEvac:
Central TX your not gonna get a drop from Don


nor North Central.. i'm sooooo sad
Member Since: Posts: Comments:
Quoting ncstorm:


Jason, wasnt you on here just yesterday when I posted model runs of pre 91L and said it was going out to sea??
Lol lol lol
Member Since: Posts: Comments:
Quoting DFWjc:
CBS 11 Weather
Made it to 100 degrees again at DFW. Streak now at 28 days.

Will the streak ever end???


Do you watch FOX4 or WFAA8?
Member Since: July 6, 2010 Posts: 113 Comments: 32255
Gonna have to get big hurricane to break the damn ridge and dry air over TX, if it means a major well, that's what it's gonna take
Member Since: Posts: Comments:
612. DFWjc
Quoting MrstormX:


Thank you, my patience is running thin today.


That is why, my friend, i'm just observing today, and not posting thoughts...
Member Since: Posts: Comments:
LLC at 10N42.8W
Member Since: Posts: Comments:
Quoting robj144:


You need to read up on nuclear physics... a nuclear based bomb can never be made without the release of radiation. That's where it gets it's energy from in the first place.

In my mind, there's no artificial way of disrupting a hurricane. Besides, hurricanes regulate sea surface temperatures, so we need them.


I am a person who also likes to learn about military weaponry and tactics like i like to learn about hurricanes, there are some weapons that produce a large modest explosion without the use of radiation it is called a MOAB uniquelly named for Mother Of All Bombs. The largest non nuclear explosion was produced from this.
Member Since: July 25, 2011 Posts: 0 Comments: 453
Quoting GHOSTY1:
okay then drop it before landfall with just enough time so that it will not be able to redevelope and if there not pricey (which they probably would be) just drop a few on it.


Sure, just enough time to drop the intensity of the storm maybe 5 mph and maximize the radiation effects... sounds good.
Member Since: Posts: Comments:
Central TX your not gonna get a drop from Don
Member Since: Posts: Comments:
Quoting washingtonian115:
Yeah I live in the city of D.c.the high is forecasted to move over here.Not so good for the folks down south.


gee...thanks, i feel the love...lol, i live in SC... my oldest son moved back here from DC a little more than a year ago...
Member Since: Posts: Comments:
Invest 91L has a long way to go yet. It's a massive circulation with multiple vortices which will take time to consolidate. Dry air is also an issue. However, gradual development is likely as it approaches the northeastern Caribbean, and I do have a feeling we will get Emily out of this at some point in that area.
Member Since: Posts: Comments:
Quoting DFWjc:


+100


Thank you, my patience is running thin today.
Member Since: Posts: Comments:
Quoting DFWjc:
CBS 11 Weather
Made it to 100 degrees again at DFW. Streak now at 28 days.

Will the streak ever end???


I am going to go out on a limb and say that yes it will eventually come to an end.
Member Since: Posts: Comments:
Quoting GHOSTY1:


Thats some pretty language coming from a blog with a pretty picture :P
Eh that's nothing compared to what I say away from this blog....
Quoting TropicalAnalystwx13:


How about Earl?
Wellllll I'm just happy that he recurved on time just before he got to the U.S.Or who knows how that would of went....
Member Since: Posts: Comments:
602. DFWjc
Quoting MrstormX:
Why are we already plotting 91Ls path to the United States it seems a little premature.


+100
Member Since: Posts: Comments:
Don mind as well die where he stands, waste of time and energy, and no rain is coming for hardly anyone, getting more rain on the upper TX coast than down there
Member Since: Posts: Comments:
Now keep in mind, we are talking long term here, but a strong trough is expected to dig down to the Gulf Coast/Florida next week. That has been a common pattern this year. That being said as it stands now 91L doesn't appear to be a much threat to Florida. But it is very long term so we will watch the system and watch to see how things develop. Also, people need to get a hold of them selves and be more patient, I'm hearing way too much talk about major hurricanes when we have a freaking invest on our hands lol. Give it time.
Member Since: Posts: Comments:
Quoting RitaEvac:
What the hell is this?? this isn't even a storm anymore, lol



I feel ya! I've seen t-storm complexes in April that were more impressive than this blob.
Member Since: Posts: Comments:
598. 882MB
WOW 91L HAS RECENTLY GOTTEN BETTER ORGANIZED IN THE LAST COUPLE OF HOURS!!ALSO AGREE THAT THIS WILL BE A VERY LARGE STORM MEANING IF IT HITS PUERTO RICO ALOT OF THE ISLANDS WILL FEEL THE FFECTS OF THIS DISTURBANCE AND THEN ONLY GOD KNOWS WHERE IT WILL GO AFTER THAT!
Member Since: Posts: Comments:
Why are we already plotting 91Ls path to the United States it seems a little premature.
Member Since: Posts: Comments:
Quoting yonzabam:


You know, I'm sick of hearing about this continual bickering about what constitutes a 'fish storm'.

If it recurves out to sea and knocks a chimney pot down in Ireland do we not call it a 'fish storm'?

If it causes some damage as a tropical storm in the Antilles, but recurves before it hits a continental land mass as a hurricane, it's understandable that people living in the US would call that a 'fish storm'. Personally, I don't have a problem with that, but some folk seem to have a need to appear as more caring human beings and be seen to be more sympathetic towards those islanders. I wonder why that is.



+1
Member Since: Posts: Comments:

Viewing: 646 - 596

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog 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.