Alex may head north to Texas or Louisiana

By: Dr. Jeff Masters , 6:36 PM GMT on June 27, 2010

Share this Blog
5
+

Tropical Depression Alex has held together fairly well during its passage over Mexico's Yucatan Peninsula, and stands poised to re-intensify back into a tropical storm once it emerges from the coast tonight. Alex brought heavy rains to northern Honduras, Mexico's Yucatan Peninsula, and Belize over the weekend. It was not a good beach day in Cozumel yesterday, as 9.25" of rain fell. Cancun received 2.05" over the weekend, and Belize City received 4.57". Satellite loops show that Alex's heavy thunderstorms are mostly gone near the center, though there are some impressive bands of precipitation well away from the center. There is an upper-level high pressure system a few hundred miles west of Alex, and the clockwise flow air around this high is bringing upper-level winds out of the northwest of about 5 knots over the storm, contributing to the 5 knots of wind shear observed in this afternoon's wind shear analysis from the University of Wisconsin's CIMSS group. Sea Surface Temperatures are very warm, 29 - 30°C, and dry air is currently not a problem for Alex.


Figure 1. Afternoon satellite image of Alex.

Forecast for Alex: which model should you trust?
While the track forecast for Alex today through Monday is fairly well-assured, the longer range forecast has become highly uncertain. An increasing number of our reliable models are now indicating Alex may take a more northerly track beginning on Tuesday, with possible landfall on the Texas coast near Galveston on Friday (according to the 8am run of the GFS model) or into western Louisiana on Wednesday (the 8am run of the Canadian model.) The key question remains how Alex will react to the trough of low pressure expected to swing down over the Eastern U.S. on Monday and Tuesday. Most of the models were predicting that the trough would not be strong enough to swing Alex to the north, and several of them continue to predict this. The 8am runs of the NOGAPS and ECMWF models, for example, take Alex into the Gulf coast of Mexico 150 miles south of Texas, on Wednesday. The GFDL and HWRF models split the difference, with the GFDL predicting a Thursday landfall in southern Texas near Brownsville, and the HWRF predicting a Thursday landfall near Corpus Christi. Morris Bender of the GFDL group has just provided me the track forecast from an improved experimental version of the GFDL that shows landfall between Corpus Christi and Galveston. So which model should you trust? Last year, the best performing models at the 3 - 4 day forecast range were the GFS and the Canadian, and these are the models that are currently calling for the more northerly track towards the upper Texas coast and Louisiana. Residents of those areas should review their hurricane preparedness plans and anticipate that Alex could make landfall as early as Wednesday in their vicinity. Residents of the Mexican coast south of Brownsville should make similar plans, as Alex could just as easily hit there.

Re-intensification of Alex is likely once the center of Alex moves offshore, though this will initially be slow due to the current disorganized state of the storm and the relatively low total ocean heat content in the 100-mile-wide stretch of water on the west side of the Yucatan Peninsula. Once Alex moves more than 100 miles from the Yucatan, total heat content of the ocean increases substantially, and Alex will have the opportunity to intensify significantly. A longer time spent over water will give Alex more of a chance to strengthen, and it is possible Alex could intensify into a major hurricane if landfall is delayed until Thursday or Friday. However, Alex's intensification may be limited the farther north it gets, as water vapor satellite images show plenty of dry air over Texas that might interfere with development. Wind shear might also be an issue for Alex if it pushes far enough north, and a slow-moving storm tends to pull up cold water from the depths, limiting intensification. In short, Alex has the potential to intensify into a major hurricane, but there are plenty of roadblocks that make this only a 10% probability in my estimation.


Figure 2. Skill of computer model forecasts for Atlantic named storms during 2009. OFCL=Official NHC forecast; GFS=Global Forecast System model; GFDL=Geophysical Fluid Dynamic Laboratory model; HWRF=Hurricane Weather Research Forecasting model; NOGAPS=Navy Operational Global Prediction System model; UKMET+United Kingdom Met Office model; ECMWF=European Center for Medium Range Weather Forecasting model; CMC=Canadian GEM model; TVCN=one of the consensus models that lends together all (or most) of the above models; BAMM=Beta and Advection Model (Medium Layer.) Image credit: National Hurricane Center 2009 verification report.

Elsewhere in the tropics
A tropical wave (Invest 94L) a few hundred miles north of the northernmost Lesser Antilles Islands has been pretty much torn apart, and is no longer a threat to develop.

Next post
Wunderground's severe weather expert Dr. Rob Carver will likely be posting an update on Alex late tonight. My next update will be Monday by 10am EDT.

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: 988 - 938

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 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73Blog Index

Quoting connie1976:
I thought that Alex wasn't LA, but now I read that some say he might? why don't any of the models say that? I'm confused...


One word answer. Wishcasters.

Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting kmanislander:


Maybe you are like the guy who got shot in the head and marvelled that he was still standing until he fell over.


Excellent!
Member Since: Posts: Comments:
I thought I saw StormW hitting the "Floor" are you ok Storm????

Taco :o)
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Let's hope this doesn't become a trend.


Well, if Alex really does bomb out, as suggested by the GFS, this could be bad... real bad...
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Rules of the Road

1. Please do not carry on personal disputes in the blogs.
2. Threats, intimidation, especially that which extends into the real world will be dealt with by extreme action.
3. Foul language is not allowed.
4. Please avoid topics that would be considered adults only. Many children come to this site looking for information about the weather.
5. Do not circumvent administrative action by creating new users, etc.
6. No spam.




all so JFV read rule 5
Member Since: May 21, 2006 Posts: 5089 Comments: 114050
Member Since: Posts: Comments:
I thought that Alex wasn't LA, but now I read that some say he might? why don't any of the models say that? I'm confused...
Member Since: Posts: Comments:
Quoting MrstormX:


No, it was used last year as well... i'll find an example if you need evidence.
Well they sure do it a lot quicker this year.
Member Since: September 2, 2009 Posts: 130 Comments: 21032
Quoting Patrap:
Logging off for the Boomer over me..

ok Pat be carful and we will see you in a bit....

TacO :o)
Member Since: Posts: Comments:
he was reported...
Member Since: Posts: Comments:
Quoting Levi32:
Alex is taking his sweet time coming off the coast....forward motion has slowed considerably.
Let's hope this doesn't become a trend.
Member Since: September 2, 2009 Posts: 130 Comments: 21032
Quoting Tazmanian:



OMG


what? what did I miss?
Member Since: Posts: Comments:
Quoting Levi32:
Alex is taking his sweet time coming off the coast....forward motion has slowed considerably.




that would give it more time overe BOC
Member Since: May 21, 2006 Posts: 5089 Comments: 114050
Quoting Acemmett90:
lol they didnt ban me
Yet.
Member Since: October 25, 2005 Posts: 19 Comments: 20686
.
Member Since: Posts: Comments:


got some rain coming for me
Member Since: July 15, 2006 Posts: 163 Comments: 52230
Quoting Stormchaser2007:
18z GFS


So, again it makes landfall in North Central TX?
Member Since: April 1, 2010 Posts: 9 Comments: 2699
.
Member Since: Posts: Comments:
Quoting kmanislander:


Maybe you are like the guy who got shot in the head and marvelled that he was still standing until he fell over.
roflmao! it's not the shot that get's 'em...it's the fall!
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
That's a new feature this year. If your comment is irrelevant to the topic or if a large sum of people report the comment, admin automatically removes it.


No, it was used last year as well... i'll find an example if you need evidence.
Member Since: May 27, 2009 Posts: 0 Comments: 4355
Quoting StormW:


WOW!
That tells you how much uncertainty the NHC has right now.
Member Since: September 2, 2009 Posts: 130 Comments: 21032
Quoting StormW:


WOW!



OMG
Member Since: May 21, 2006 Posts: 5089 Comments: 114050
Quoting kmanislander:


Maybe you are like the guy who got shot in the head and marvelled that he was still standing until he fell over.
lmao
Member Since: Posts: Comments:
961. xcool
Admins on watiching .
Member Since: Posts: Comments:
Quoting Weather456:
"Alex may head north to Texas or Louisiana"

Highly doubt so


Same.
Member Since: Posts: Comments:
Alex is taking his sweet time coming off the coast....forward motion has slowed considerably.
Member Since: November 24, 2005 Posts: 628 Comments: 26455
18z GFS
FULL IMAGE
Member Since: Posts: Comments:
"Alex may head north to Texas or Louisiana"

Highly doubt so
Member Since: Posts: Comments:
Logging off for the Boomer over me..

Member Since: Posts: Comments:
Quoting CaneWarning:
913. Wow, admin is quick these days.



yup
Member Since: May 21, 2006 Posts: 5089 Comments: 114050
Member Since: Posts: Comments:
Quoting jlp09550:


But your comment just got removed. :)
That's a new feature this year. If your comment is irrelevant to the topic or if a large sum of people report the comment, admin automatically removes it.
Member Since: September 2, 2009 Posts: 130 Comments: 21032
Quoting Acemmett90:
taz how did i not get banned


Maybe you are like the guy who got shot in the head and marvelled that he was still standing until he fell over.
Member Since: Posts: Comments:
18z GFS still trending further west....has Alex moving very slowly off the SE TX coast at 96 hours.

Member Since: November 24, 2005 Posts: 628 Comments: 26455
18Z GFS Tx/La border
Member Since: Posts: Comments:
913. Poof!
Member Since: Posts: Comments:
913. Wow, admin is quick these days.
Member Since: Posts: Comments:
Center moving offshore

Member Since: Posts: Comments:
Quoting Acemmett90:

well im takeing it off now



lol the Admin did it for you
Member Since: May 21, 2006 Posts: 5089 Comments: 114050
Quoting Stormchaser2007:


Yes

But they base intensity off of winds not pressure. Though most of the time the winds will catch up to the pressure.


There is a lag on the way down and on the way up. Tropical cyclones are like huge wheels, they take time to spin up and spin down. The lower the pressure the higher the winds the more intense the system. They are all linked.
Member Since: Posts: Comments:
Quoting Hurricanes101:


Winds are a difference in pressure, that pressure stayed at 999mb, would not be shocked to see the winds go up and Alex become a TS again tonight
Earlier today I called for a TS tonight, let's see if I'm right.

Depending on what recon shows will be the determining factor of whether or not we get a TS tonight though.
Member Since: September 2, 2009 Posts: 130 Comments: 21032
Quoting Acemmett90:
lol they didnt ban me


But your comment just got removed. :)
Member Since: Posts: Comments:

Viewing: 988 - 938

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 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73Blog Index

Top of Page

About JeffMasters

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
55 °F
Overcast