Alex continues to slowly organize

By: Dr. Jeff Masters , 7:17 PM GMT on June 28, 2010

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Tropical Storm Alex continues to slowly grow more organized as it steams away from Mexico's Yucatan Peninsula. Satellite loops show that Alex's heavy thunderstorms continue to increase in areal extent, and low level spirals bands are slowly building to the south and north. The clockwise flow around an upper-level high pressure system a few hundred miles west of Alex is bringing about 15 knots of wind shear to the storm, which is slowing intensification. Heavy thunderstorm activity is limited on the storm's northwest side, thanks to the shear and some dry continental air flowing off the coast of North America. Sea Surface Temperatures are very warm, 29°C. The latest Hurricane Hunter center fix, at 12:07 pm CDT, showed a central pressures of 990 mb, a 1 mb rise in six hours. Top winds were holding steady near 60 mph. Alex has stalled out the last few hours, as it began to "feel" the trough of low pressure to its north breaking down the high pressure ridge that has been pushing the storm to the west-northwest. This stall has allowed the storm to churn up cold water from the depths, which is probably interfering with development. Satellite loops show that Alex has a very large circulation covering about 2/3 of the Gulf of Mexico. We can expect that should Alex become a Category 2 or stronger hurricane, its storm surge will affect a much wider stretch of coast than Hurricane Dolly of 2008 did.


Figure 1. Afternoon satellite image of Alex.

Track forecast for Alex
The latest 12 UTC (7am CDT) runs of our most reliable computer models have come into much better agreement. A consensus forecast arrived at by averaging together most or all of the tracks of our top models--the GFS, ECMWF, GFDL, NOGAPS, HWRF, UKMET, and GFDN--is pretty much what NHC always uses as the basis of their forecast. This consensus forecast has narrowed in on the region just south of the Texas/Mexico border as being the most likely landfall location, with the usual cone of uncertainty surrounding it. The computer model that had been making the northernmost landfall predictions, the Canadian model, is now projecting a landfall 100 miles south of the Texas/Mexico border. There has been a general southward shift of the models in their latest runs, and the most northerly landfall location, near Port Mansfield, is now being predicted by the HWRF model. The earliest landfall time is Wednesday morning, and the latest is Thursday morning. Which model should you trust? Last year, the best performing models at the 3 day forecast period were the GFS, Canadian, ECMWF, and GFDL.

With steering currents relatively weak, the uncertainty in landfall location is high. The average error in an NHC 72-hour track forecast last year was 230 miles, which is about the distance from Brownsville to Port O'Connor. Consider also that the NHC cone of uncertainty is the region where 2/3 of the time (using the last 5 years of statistics) the center of a storm will go. Forecast errors tend to be equally large along track (speed errors) and cross-track (deviations from side-to-side), so that means that about 20% of the time a storm will not be in the cone of uncertainty. Given the slow motion of Alex and the recent uncertainty of the computer models, people living just beyond the edge of the cone of uncertainty should not be confident yet that Alex will miss them.

To get the probability of receiving tropical storm force winds or hurricane force winds for your location, I recommend the NHC wind probability forecasts. The 10am CDT (15 UTC) wind probability product predicted that Brownsville, Texas had the highest odds of getting a direct hit from Alex:

Brownsville, TX: 67% chance of tropical storm conditions (winds 39+ mph), 16% chance of hurricane force winds (74+ mph). This is the cumulative probability through Saturday morning. The wind probability forecasts also include separate probabilities for each 12-hour period between now and three days from now, and each 24 hours for the period 4 - 5 days from now.

La Pesco, MX: 49% tropical storm, 6% hurricane.

Tampico, MX: 31% tropical storm, 4% hurricane.

Corpus Christi, TX: 45% tropical storm, 6% hurricane.

Freeport, TX: 23% tropical storm, 2% hurricane.

Galveston, TX: 21% tropical storm, 1% hurricane.


Figure 2. Skill of computer model forecasts of 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.

Uncertainty in the NHC Cone of Uncertainty
A research project funded by NOAA known as the Joint Hurricane Testbed has produced a remarkable number of tools now in operational use at the National Hurricane Center to improve hurricane forecasts and warnings. One of these projects, called "Prediction of Consensus TC Track Forecast Error and Correctors to Improve Consensus TC Track Forecasts", was an effort by Dr. Jim Goerss at the Navy Research Lab to improve the accuracy of the NHC "cone of uncertainty" (AKA the "Cone of Death") showing where a storm is expected to track 2/3 of the time. The radius of the circles that make up the cone are based on error statistics of the official NHC forecast over the past five years. We can expect in certain situations, such as when the models are in substantial disagreement, a consensus forecast made using these models will have much greater than average errors. Since the NHC typically bases their forecast on a consensus forecast made using a combination of reliable hurricane forecasting models, it is instructive to view the "GPCE" (Goerss Prediction Consensus Error) circles to see if the uncertainty cone should be smaller or larger than usual. The consensus forecast I'll look at is called "TVCN", and is constructed by averaging the track forecasts made by most of (or all) of these models: GFS, ECMWF, NOGAPS, GFDL, HWRF, GFDN, and UKMET. In the case of this morning's 12 UTC (7am CDT) June 28 run of these models, here is what the radius of the "cone of uncertainty" should be, in nautical miles:

12 hours: 42 nm
24 hours: 73 nm
36 hours: 96 nm
48 hours: 112 nm
72 hours: 173 nm
96 hours: 327 nm
120 hours: 376 nm

And here is the radius of NHC's "cone of uncertainty" for their official forecast, based on the average errors for the past five years:

12 hours: 36 nm
24 hours: 62 nm
36 hours: 85 nm
48 hours: 108 nm
72 hours: 161 nm
96 hours: 220 nm
120 hours: 285 nm

So, the GPCE error estimates are showing that the latest forecasts for Alex out to 72 hours are 4% - 17% higher in uncertainty than average. The 4 - 5 day forecasts are 32% - 49% more uncertain than average--but of course, we expect Alex to be inland at those times.

Intensity forecast for Alex
Alex is currently over a region of ocean with relatively low total ocean heat content (about 10 - 30 kJ/cm^2). By Tuesday and Wednesday, the heat content will increase to 40 - 70 kJ/cm^2, which is high enough to allow Alex to rapidly intensify. Wind shear is currently a moderate 15 knots, and is projected by the SHIPS model to decrease to the low range, below 10 knots, on Tuesday and Wednesday. The combination of low wind shear and high ocean heat content should allow Alex to intensify into a hurricane. NHC is giving Alex a 78% chance of being a hurricane on Wednesday morning, and a 16% chance it will be a major hurricane at that time. Water vapor satellite images, though, show plenty of dry air over Texas and the adjoining waters, and this dry air may turn out to be a significant detriment to Alex. Another factor limiting Alex's intensification may be that the atmosphere is more stable than usual right now--temperatures at 200 mb are a rather warm -50°C, and are expected to warm an additional 1 - 2 degrees by Wednesday. Another factor limiting Alex's intensification may be its slow forward speed. Alex has already stalled out once, and may stall out later in its path, as well. A stalled-out 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 enough roadblocks that I give a 20% chance of this happening.

Elsewhere in the tropics
None of the reliable computers models is calling for tropical storm formation over the the next seven days in the Atlantic.

Wind and ocean current forecast for the BP oil disaster
It currently appears that Alex will not directly affect the oil slick location, other than to bring 2 - 4 foot swells to the region on Wednesday. However, because Alex is such a deep low pressure region, strong southeast winds of 15 - 25 knots will blow over the oil slick region today through Wednesday, according to the latest marine forecast from NOAA. The resulting currents should act to push oil to the west and northwest onto portions of the Louisiana, Mississippi, and Alabama coasts, according to the latest trajectory forecasts from NOAA and the State of Louisiana. Oil will also move westward along the central Louisiana coast towards the Texas border.

Resources for the BP oil disaster
Map of oil spill location from the NOAA Satellite Services Division
My post, What a hurricane would do the Deepwater Horizon oil spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
NOAA's interactive mapping tool to overlay wind and ocean current forecasts, oil locations, etc.
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Portlight continues its Haiti response
Hurricane season is here, and Haiti is not ready. Over 1.5 million Haitians are living outside in tents or under tarps, and are highly vulnerable to a hurricane. Portlight is working on constructing steel shelters out of shipping containers for homeless Haitians, as detailed in the Haitian Relief Recap blog post. Please visit the Portlight.org web site or the Portlight blog to learn more and to donate to Portlight's efforts in Haiti.


Figure 3. Still frame from the remarkable video taken inside the Haitian Presidential Palace during the 2010 earthquake.

To remind people of just how devastating the earthquake was, the Haitian government released a video earlier this month showing the inside of the Haitian Presidential Palace during the mighty Haitian earthquake.

Next post
Dr. Rob Carver is planning on making a post late tonight, and I'll have an update by 9:30am CDT on Tuesday.

Jeff Masters

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central dense overcast
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Quoting Patrap:


I gotz to say..maybe.

Just maybe were seeing the reformation process begin as that older CoC is toast points.

Note the Older Coc lose out

i agree. to the one who wants stats with comments- this is an opinion blog. even the experts are just guessing and so far have been kinda wrong. not one met. or expert has said that this would stall out for so long. usually when a storm stalls its cuz its changing direction or relocating coc. Alex is not all the powerful yet. its just big. its still a tropical storm, not a hurricane. coc's have relocated before in tropical storms and hurricanes. nothing is impossible.
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Quoting LaCoast:
TH check this link out tell me what you see.
http://www.ssec.wisc.edu/data/geo/index.php?satellite=east&channel=vis&coverage=conus&f ile=jpg&imgo ranim=8

I see a pony!

No, but seriously, I see a very large system
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Quoting MiamiHurricanes09:
The cone got smaller; the watches and warnings grew larger.


Hmmm, they didn't include the Cali/AZ border like GFDL does...I wonder whose right.
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I think the models will go North tonight with this new data they have. Personally I wouldve just left the line at Mex/Tex border but thats just me and im not a expert.
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Quoting Hurricanes101:


How is Alex not going to be a GOM factor? He is in the BOC with the potential to grow stronger as he moves north


Northwest, I believe. I mean Alex will have little impact on the N. Gulf where I am. No oil please.
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Quoting StormSurgeon:


I don't believe there are any upwelling issues in the GOM. West Africa and West S. America are where they normally occur, as well as the American West Coast.


I was just piggybacking on a earlier comment that the waters where the storm is now are pretty shallow and that upwelling of cooler waters may be inhibiting convection around the COC........Seems right to me at the moment.
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Quoting MiamiHurricanes09:
Wow! No one posted an advisory.


Here's one for you:

000
WTNT31 KNHC 282031
TCPAT1
BULLETIN
TROPICAL STORM ALEX ADVISORY NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010
400 PM CDT MON JUN 28 2010

...ALEX MOVING NORTH-NORTHWEST...TROPICAL STORM WATCH ISSUED FOR
PORTIONS OF THE TEXAS COAST...


SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...20.5N 91.8W
ABOUT 410 MI...660 KM ESE OF TAMPICO MEXICO
ABOUT 520 MI...835 KM SE OF BROWNSVILLE TEXAS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/HR
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 5 MPH...7 KM/HR
MINIMUM CENTRAL PRESSURE...990 MB...29.23 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR THE COAST OF TEXAS FROM
BAFFIN BAY TO PORT OCONNOR.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WATCH IS IN EFFECT FOR...
* THE COAST OF TEXAS SOUTH OF BAFFIN BAY TO THE MOUTH OF THE RIO
GRANDE
* THE COAST OF MEXICO FROM THE MOUTH OF THE RIO GRANDE TO LA CRUZ

A TROPICAL STORM WATCH IN IN EFFECT FOR...
* THE COAST OF TEXAS FROM BAFFIN BAY TO PORT OCONNOR

A HURRICANE WARNING COULD BE REQUIRED FOR A PORTION OF THE HURRICANE
WATCH AREA TONIGHT.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA. A WATCH IS TYPICALLY ISSUED 48 HOURS
BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM-FORCE
WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR
DANGEROUS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED
STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE
MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE
FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE
UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL
METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 400 PM CDT...2100 UTC...THE CENTER OF TROPICAL STORM ALEX WAS
LOCATED NEAR LATITUDE 20.5 NORTH...LONGITUDE 91.8 WEST. ALEX IS
MOVING TOWARD THE NORTH-NORTHWEST NEAR 5 MPH...7 KM/HR. AN INCREASE
IN FORWARD SPEED AND A TURN TOWARD THE NORTHWEST ARE EXPECTED ON
TUESDAY...FOLLOWED BY A TURN TOWARD THE WEST-NORTHWEST ON
WEDNESDAY. ON THE FORECAST TRACK...ALEX WILL MOVE ACROSS THE
SOUTHERN GULF OF MEXICO AND APPROACH THE COAST WITHIN THE HURRICANE
WATCH AREA LATE WEDNESDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 60 MPH...95 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND ALEX IS EXPECTED TO BECOME A HURRICANE ON TUESDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER. AN AUTOMATED STATION FROM THE MEXICAN NAVY AT CAYO
ARCAS RECENTLY REPORTED A SUSTAINED WIND OF 33 MPH...53 KM/HR...AND
A GUST OF 40 MPH...65 KM/HR.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 990 MB...29.23 INCHES.
THE MEXICAN NAVY STATION AT CAYO ARCAS RECENTLY REPORTED A PRESSURE
OF 992 MB...29.29 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...ALEX IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL
ACCUMULATIONS OF 3 TO 6 INCHES OVER SOUTHERN MEXICO AND THE YUCATAN
PENINSULA THROUGH TUESDAY. ISOLATED MAXIMUM AMOUNTS OF 10 INCHES
ARE POSSIBLE OVER MOUNTAINOUS AREAS. THESE RAINS COULD CAUSE
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.

HEAVY RAINS COULD REACH THE COASTAL AREAS OF TAMAULIPAS AND NORTHERN
VERACRUZ OF MEXICO AND SOUTH TEXAS TUESDAY NIGHT AND WEDNESDAY.

WIND...TROPICAL STORM CONDITIONS ARE EXPECTED TO APPROACH THE COAST
WITHIN THE HURRICANE AND TROPICAL STORM WATCH AREAS ON WEDNESDAY...
MAKING OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...700 PM CDT.
NEXT COMPLETE ADVISORY...1000 PM CDT.

$$
FORECASTER BRENNAN

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Is Houston/Galveston in the clear?? Looks like it by the computer models, correct?
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Quoting StormChaser81:


It needs to get it act together, Cat 1 isnt worth chasing. will weaken probably pretty quickly during landfall and then you just in a TS.


Thanks for the input! Why don't you post that over on his blog?
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thanks storm and angiest.
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National hurricane center really dropped it south this time into mexico.They seem to be alot more confident it will go to mexico.
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Quoting truecajun:
what is CDO?


Central Dense Overcast. A solid mass of convection around the center. It gets built up primarily during the tropical storm phase, and eventually an eye emerges from it.

Right now, Alex doesn't have much that you could call a CDO; you can still see the low level cumulus swirl on vis pretty easily. But as you'll note on IR, the dense convection is closing in on all sides, so it may have a CDO by tonight. A CDO is necessary for significant intensification.
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Quoting atmoaggie:
Cash Delivery On

lol
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Member Since: July 3, 2005 Posts: 426 Comments: 128875
TROPICAL DEPRESSION DARBY ADVISORY NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP052010
200 PM PDT MON JUN 28 2010

...DARBY IS NO LONGER A TROPICAL CYCLONE...
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Spoke too soon... LOL.
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Quoting winter123:
Alex is a naked swirl. NEXT


If we listened to you we would've said next last week when you predicted it wouldn't form.
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The cone got smaller; the watches and warnings grew larger.

Member Since: Posts: Comments:
..ALEX MOVING NORTH-NORTHWEST...TROPICAL STORM WATCH ISSUED FOR
PORTIONS OF THE TEXAS COAST...


SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...20.5N 91.8W
ABOUT 410 MI...660 KM ESE OF TAMPICO MEXICO
ABOUT 520 MI...835 KM SE OF BROWNSVILLE TEXAS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/HR
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 5 MPH...7 KM/HR
MINIMUM CENTRAL PRESSURE...990 MB...29.23 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR THE COAST OF TEXAS FROM
BAFFIN BAY TO PORT OCONNOR.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WATCH IS IN EFFECT FOR...
* THE COAST OF TEXAS SOUTH OF BAFFIN BAY TO THE MOUTH OF THE RIO
GRANDE
* THE COAST OF MEXICO FROM THE MOUTH OF THE RIO GRANDE TO LA CRUZ

A TROPICAL STORM WATCH IN IN EFFECT FOR...
* THE COAST OF TEXAS FROM BAFFIN BAY TO PORT OCONNOR

A HURRICANE WARNING COULD BE REQUIRED FOR A PORTION OF THE HURRICANE
WATCH AREA TONIGHT.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA. A WATCH IS TYPICALLY ISSUED 48 HOURS
BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM-FORCE
WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR
DANGEROUS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED
STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE
MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE
FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE
UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL
METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 400 PM CDT...2100 UTC...THE CENTER OF TROPICAL STORM ALEX WAS
LOCATED NEAR LATITUDE 20.5 NORTH...LONGITUDE 91.8 WEST. ALEX IS
MOVING TOWARD THE NORTH-NORTHWEST NEAR 5 MPH...7 KM/HR. AN INCREASE
IN FORWARD SPEED AND A TURN TOWARD THE NORTHWEST ARE EXPECTED ON
TUESDAY...FOLLOWED BY A TURN TOWARD THE WEST-NORTHWEST ON
WEDNESDAY. ON THE FORECAST TRACK...ALEX WILL MOVE ACROSS THE
SOUTHERN GULF OF MEXICO AND APPROACH THE COAST WITHIN THE HURRICANE
WATCH AREA LATE WEDNESDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 60 MPH...95 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND ALEX IS EXPECTED TO BECOME A HURRICANE ON TUESDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER. AN AUTOMATED STATION FROM THE MEXICAN NAVY AT CAYO
ARCAS RECENTLY REPORTED A SUSTAINED WIND OF 33 MPH...53 KM/HR...AND
A GUST OF 40 MPH...65 KM/HR.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 990 MB...29.23 INCHES.
THE MEXICAN NAVY STATION AT CAYO ARCAS RECENTLY REPORTED A PRESSURE
OF 992 MB...29.29 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...ALEX IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL
ACCUMULATIONS OF 3 TO 6 INCHES OVER SOUTHERN MEXICO AND THE YUCATAN
PENINSULA THROUGH TUESDAY. ISOLATED MAXIMUM AMOUNTS OF 10 INCHES
ARE POSSIBLE OVER MOUNTAINOUS AREAS. THESE RAINS COULD CAUSE
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.

HEAVY RAINS COULD REACH THE COASTAL AREAS OF TAMAULIPAS AND NORTHERN
VERACRUZ OF MEXICO AND SOUTH TEXAS TUESDAY NIGHT AND WEDNESDAY.

WIND...TROPICAL STORM CONDITIONS ARE EXPECTED TO APPROACH THE COAST
WITHIN THE HURRICANE AND TROPICAL STORM WATCH AREAS ON WEDNESDAY...
MAKING OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...700 PM CDT.
NEXT COMPLETE ADVISORY...1000 PM CDT.

$$
FORECASTER BRENNAN
Member Since: Posts: Comments:
TH check this link out tell me what you see.
http://www.ssec.wisc.edu/data/geo/index.php?satellite=east&channel=vis&coverage=conus&file=jpg&imgo ranim=8
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Quoting truecajun:
what is CDO?
Cash Delivery On
(sry, knew others would beat me to it, anyway)
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NHC just updated there new map and moves the storm farther south than before. As so as the other models predicted.

Member Since: July 9, 2008 Posts: 8 Comments: 334
Alex is a naked swirl. NEXT
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Quoting weathermanwannabe:
Just making the observation that the upwelling issue in shallow waters, and, dry air entrainment from the NW of Alex is really causing him some problems in the short-term which includ the lack of significant convection near the COC.....That may certainly change over time but Alex having a tough time right now me thinks.


I don't believe there are any upwelling issues in the GOM. West Africa and West S. America are where they normally occur, as well as the American West Coast.
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Quoting truecajun:
what is CDO?


Central Dense Overcast. The area of thick clouds and thunderstorms over the main body of the storm. In a well-formed system the CDO should cover the center. In a very well formed storm the eye is in the middle of it.
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4:00 PM CDT Mon Jun 28
Location: 20.5°N 91.8°W
Max sustained: 60 mph
Moving: NNW at 5 mph
Min pressure: 990 mb
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Something seems wrong with that. Crazy lol.
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Quoting 1900hurricane:

Not necessarily. Dolly was only a category 1 a landfall (although top end), and Oz's video from Dolly was exceptional! Check it out here.


I've seen it, im on his hurricane chasing team.
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Quoting RitaEvac:
I'm willing to bet the models go back north after this southward trend.


why?
Member Since: July 2, 2009 Posts: 0 Comments: 2811
I'm willing to bet the models go back north after this southward trend.
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271. Asta
regardless of where Alex makes landfall-
as Dr. Masters indicated-
it is a large system and
will impact a large area in the GOM:

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE NEW ORLEANS LA
327 PM CDT MON JUN 28 2010

...COASTAL FLOOD WATCH IN EFFECT THROUGH WEDNESDAY EVENING...

http://forecast.weather.gov/showsigwx.php?warnzone=LAZ062&warncounty=LAC071&firewxzone=LAZ062&local _place1=New+Orleans+LA&product1=Coastal+Flood+Watch
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what is CDO?
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Quoting LaCoast:
It's pretty clear He ain't movin much.Link


Furthermore I don't see a ridge building. I am no expert though.
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NNW at 5, winds still 60.
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Quoting StormChaser81:


It needs to get it act together, Cat 1 isnt worth chasing. will weaken probably pretty quickly during landfall and then you just in a TS.

Not necessarily. Dolly was only a category 1 a landfall (although top end), and Oz's video from Dolly was exceptional! Check it out here.
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Quoting angiest:
New advisory...


little south again....
Member Since: July 2, 2009 Posts: 0 Comments: 2811
Quoting Skyepony:


The last few frames hints to a wobble NW but yeah.. & takes away alot of confusion of where the storm's center is for ya'll looking at IR.. I couldn't get the several most recent frames to come up on the RGB loop either, so MIMIC was a big surprise.


Skye, don't forget this if SSD doesn't update. It has rapid-scan frames every 5-15 minutes, which is both a blessing and a curse because the temporal resolution is awesome but the loop isn't long enough to see really long-term trends in motion.
Member Since: November 24, 2005 Posts: 635 Comments: 26661
TS Watch from Baffin Bay to Port O'Connor.
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Quoting StormSurgeon:


Your avatar is sooooo cool, but Alex is not going to be a GOM factor. More to come though.


How is Alex not going to be a GOM factor? He is in the BOC with the potential to grow stronger as he moves north
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Quoting whs2012:


I think this is going due north not NW...IMO


yeah. the last few frames seemed N
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Quoting Grothar:


I know Jimmy Stewart wouldn't have liked it.
Jim Morrison would.:) Wuzup Gro.
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Quoting KarenRei:


You don't use convective bursts to find the COC; by definition, those are high altitude. You use the low-level cumulus clouds. They very clearly show the same COC as ever. This storm actually has a beautiful low level cyclonic flow, reaching all the way out to Darby, as another poster recently noted. It's about as far from a center relocation as you can get. I have no clue where you're getting this notion from.


Sperience maybe.

Its just my Obs on the situ..

Worlds wont collide if im incorrect.


Member Since: July 3, 2005 Posts: 426 Comments: 128875
New advisory...
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Quoting hydrus:
What happened? It looks like a poster from the 60,s.


Yeah, 1968, (I think???) LOL
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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