ATL : TROPICAL DEPRESSION ALEX - MODELS

[Nederlander]

NHC says the current heading is 300.. here is the newest forecast.. surprised it wasnt farther north.. The disco was very very interesting though

[KWT]

Thats ECM brings Texas very much back into the game, the models certainly are shifting back northwards again compared to yesterday...

Looking quite likely this will be a strong hurricane upon landfall given the models, and now I'm thinking this really could end up a S.Texas risk...

[cycloneye]

The 06z GFS is with a Galveston landfall.

[KWT]

Yep current GFS still going for a TX/LA landfall pretty close to where Ike hit 5 years ago. The only good news is the heat content with the shelf water is still very low and probably wouldn't be supportive of much above a 85-90kt hurricane I'd have thought, esp with a large system like this...but thats still more nthen enough really!

[sphelps8681]

On that model run what is the intensity of the storm hitting Tx/La.

Thanks

[rockyman]

6z HWRF: Brownsville 966 mb (northward shift by 175 miles from 0z)

[Stratosphere747]

6z HWRF -

[KWT]

65kts hurricane into Brownsville...thats not a great situation less then two years after Dolly hit a similar region at a similar strength...

Certainly needs to be watched, its trended northwards again since the last run again...looks just to the north of the ECM this time round...I feel another slight northward adjustment from the NHC.

[cycloneye]

06z GFDL landfall is just south of Brownsville.

455
WHXX04 KWBC 271120
CHGQLM
ATTENTION...NATIONAL HURRICANE CENTER

NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR

TROPICAL STORM ALEX 01L

INITIAL TIME 6Z JUN 27

DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT
REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD
NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC
OFFICIAL FORECAST.


FORECAST STORM POSITION

HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)

0 18.0 89.1 290./ 9.9
6 18.6 89.8 309./ 9.3
12 19.3 90.6 311./10.1
18 20.1 91.1 328./ 8.6
24 20.6 91.9 304./ 9.6
30 21.0 92.2 316./ 4.9
36 21.4 92.3 351./ 3.9
42 21.9 92.6 329./ 5.9
48 22.1 93.1 296./ 4.7
54 22.5 93.6 307./ 6.6
60 22.9 93.9 321./ 4.3
66 23.4 94.4 318./ 7.2
72 24.0 95.1 305./ 8.7
78 24.2 96.0 288./ 8.0
84 24.6 96.7 294./ 7.9
90 24.5 97.6 269./ 7.5
96 24.4 98.5 263./ 8.4
102 23.7 99.4 231./11.5
108 23.1 100.9 248./14.3
114 23.1 102.0 270./10.5
120 23.3 103.1 281./10.4
126 24.1 103.7 323./ 9.9

[rockyman]

06z GFDL landfall is just south of Brownsville.

455
WHXX04 KWBC 271120
CHGQLM
ATTENTION...NATIONAL HURRICANE CENTER

NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR

TROPICAL STORM ALEX 01L

INITIAL TIME 6Z JUN 27

DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT
REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD
NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC
OFFICIAL FORECAST.


FORECAST STORM POSITION

HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)

0 18.0 89.1 290./ 9.9
6 18.6 89.8 309./ 9.3
12 19.3 90.6 311./10.1
18 20.1 91.1 328./ 8.6
24 20.6 91.9 304./ 9.6
30 21.0 92.2 316./ 4.9
36 21.4 92.3 351./ 3.9
42 21.9 92.6 329./ 5.9
48 22.1 93.1 296./ 4.7
54 22.5 93.6 307./ 6.6
60 22.9 93.9 321./ 4.3
66 23.4 94.4 318./ 7.2
72 24.0 95.1 305./ 8.7
78 24.2 96.0 288./ 8.0
84 24.6 96.7 294./ 7.9
90 24.5 97.6 269./ 7.5
96 24.4 98.5 263./ 8.4
102 23.7 99.4 231./11.5
108 23.1 100.9 248./14.3
114 23.1 102.0 270./10.5
120 23.3 103.1 281./10.4
126 24.1 103.7 323./ 9.9

Scary how it turns Alex almost due north in 36 hours, before bending it back to the west.

http://moe.met.fsu.edu/cgi-bin/gfdltc2. ... =Animation

[ronjon]

Well with the 06Z HWRF shifting north and most of the GFS ensemble members showing a SW La landfall things are changing fast. I'll add more fuel to the debate, the ECM ensemble mean takes Alex northward off the mid-Texas coast.

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!MSLP!North%20America!96!pop!od!enfo!plot_ensm_essential!2010062700!!chart.gif

[KWT]

GFDL gets upto 24.6N which is a little further north than the 0z GFDL run, the worrying thing is with this run TS winds probably would get into Texas and it really wouldn't need much shifting north to get the core very close to Texas indeed on that GFDL run...

Things have a long way to go yet people!

[KWT]

Well with the 06Z HWRF shifting north and most of the GFS ensemble members showing a SW La landfall things are changing fast. I'll add more fuel to the debate, the ECM ensemble mean takes Alex northward off the mid-Texas coast.

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!MSLP!North%20America!96!pop!od!enfo!plot_ensm_essential!2010062700!!chart.gif

Isn't the system off the Mexico coast at 96hrs on that chart?

However there does seem to be some real uncertainty about this system right now and the ensembles do seem to be more scattered thats for sure. Do you have the link to the GFS ensembles by the way?

[ronjon]

Well with the 06Z HWRF shifting north and most of the GFS ensemble members showing a SW La landfall things are changing fast. I'll add more fuel to the debate, the ECM ensemble mean takes Alex northward off the mid-Texas coast.

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!MSLP!North%20America!96!pop!od!enfo!plot_ensm_essential!2010062700!!chart.gif

Isn't the system off the Mexico coast at 96hrs on that chart?

However there does seem to be some real uncertainty about this system right now and the ensembles do seem to be more scattered thats for sure. Do you have the link to the GFS ensembles by the way?

KWT, on the left chart you notice that tiny speck of white - thats the mean position for the ECM ensemble members. Below is a neat site where you can click on all the individual model runs. The AP members (20 total) under later cycle guidance are the GFS ensemble members.

http://tropicalatlantic.com/plots/01-googlemaps.shtml

[KWT]

So I'm guessing the right hand side isn't the ECM mean but the ECM operational run and the ensembles SD is what is on the right side. I spose that does make sense!

ps, thanks for that link, the GFS ensembles seem to bend back west but not enough to take it inland before it lifts back northwards again.

[wxsouth]

Well with the 06Z HWRF shifting north and most of the GFS ensemble members showing a SW La landfall things are changing fast. I'll add more fuel to the debate, the ECM ensemble mean takes Alex northward off the mid-Texas coast.

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!MSLP!North%20America!96!pop!od!enfo!plot_ensm_essential!2010062700!!chart.gif

Isn't the system off the Mexico coast at 96hrs on that chart?

However there does seem to be some real uncertainty about this system right now and the ensembles do seem to be more scattered thats for sure. Do you have the link to the GFS ensembles by the way?

KWT, on the left chart you notice that tiny speck of white - thats the mean position for the ECM ensemble members.

This is not correct...The shading with the speck of white is the standard deviation of the ensemble sfc pressure field. The mean of the ensembles is contoured and centered off south texas/northern mexico. What the plot does imply is that there are members of the ensemble that take Alex farther north.

[KWT]

Ah thats what I thought wxsouth!

The right hand chart is the SD of the ensembles, which does suggest there is certainly a decent split in the ensembles.

[srainhoutx]

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
330 AM EDT SUN JUN 27 2010

VALID 12Z THU JUL 01 2010 - 12Z SUN JUL 04 2010

DETERMINISTIC/ENSEMBLE SPREAD IS UNUSUALLY SMALL TO BEGIN THE
MEDIUM RANGE PERIOD DUE IN PART TO A HIGH AMPLITUDE OMEGA-BLOCK
EXTENDING FROM BRITISH COLUMBIA INTO QUEBEC. HOWEVER...
THE BLOCK IS EXPECTED TO SLOWLY ERODE DAYS 4-5 BEFORE COMPLETELY
DISSIPATING WITH THE RESIDUAL LONGWAVE PATTERN PROGRESSING
EASTWARD DAYS 6-7. THE MOST NOTABLE MODEL DIFFERENCES ARE EMBEDDED
WITHIN THE WESTERN TROUGH SEGMENT OF THE OMEGA-BLOCK AS ITS BEGINS
TO ERODE...
WITH THE 00Z GFS FASTER THAN THE 00Z ECMWF IN LIFTING THE TROUGH
OUT OF THE WEST DAYS 3-4 BUT SLOWER THAN THE 00Z ECMWF IN
REINFORCING THE TROUGH DAYS 5-6.

MEANWHILE...IN THE GULF OF MEXICO ALL BUT THE 00Z ECMWF/UKMET
MANIFEST CONVECTION NORTH OF THE TRACK OF TROPICAL STORM ALEX
AFTER IT CROSSES THE YUCATAN PENINSULA WHICH IN TURN SUFFICIENTLY
ERODES THE SUBTROPICAL RIDGE TO STEER ALEX TOWARD PORT ARTHUR BY
DAY 5...A SCENARIO NOT SUPPORT BY THE BULK OF GUIDANCE...THE
OFFICIAL NHC FORECAST...AND COORDINATED HPC/NHC POINTS FROM
YESTERDAY. THUS...WILL HONOR FORECAST CONTINUITY WITH ALEX WITH
ONLY MINOR ADJUSTMENTS ANTICIPATED THIS PACKAGE. OTHERWISE...THE
PRESSURES/FRONTS WILL BE CREATED USING 100 PERCENT OF THE 00Z
ECMWF DAY 3 BEFORE INCORPORATING INCREASING AMOUNTS OF THE 12Z
ECMWF ENSEMBLE MEAN DAYS 4-7...WITH THE BLEND BY DAY 7
APPROXIMATELY 1/3 ECMWF TO 2/3 ECMWF ENSEMBLE MEAN.

JAMES

[gatorcane]

So right now it looks like the GFS/CMC vs the rest of the models with the HWRF somewhere inbetween?

Pretty good showdown here although more models show Mexico still. If the GFS/CMC verify and Alex somehow manages to get pulled north, even into SE Texas/LA border area, that would be quite victory for those models when most are not showing that solution.

I haven't seen anybody post the UKMET. Here is the 00Z:

[KWT]

Yep Gatorcane, though the ECM/HWRF have shifted northwards as well, though your right the C/N Mexico region looks the most likely looking at the models...I think the general idea the ECM has looks pretty good to me with a landfall close to where the NHC are expecting.