Disclaimer: This site is not affiliated with the National Hurricane Center, Hurricane Hunters, Storm Prediction Center, or National Weather Service. ALL forecasts herein are the result of my analysis, and I am solely responsible for the content.
(T. F. “Storm” Walsh III)
For those who have donated to my site, your help has been greatly appreciated. For those not aware, donations to my site help me offset my out of pocket expenses…such as some of the model maps you view on here, which are only available due to my subscription to the corresponding sites. The F5 Data maps I post as well, is another out of pocket expense (monthly subscription). Updates to software (weather related), and costs for my domain name are also out of pocket to me. To donate, please click the DONATE button to the right. Any help you provide is immensely appreciated! Without your help, I may not be able to continue paying the monthly subscription charges for access to all of the best information I use in my forecasts.
STORM W’s SEASONAL HURRICANE FORECAST
TOTAL STORMS: 14-16
MAJ. HURRICANES: 3-4
MAJ. HURRICANES: 0
U.S. LANDFALLS: 1
Good evening all!
Well, it was a bit of a surprise, seeing the struggle of the disturbance in satellite loop imagery earlier, but as of 5:00 p.m. EDT, the NHC named the disturbance approaching the Lesser Antilles, Tropical Storm DON. Hurricane Hunter aircraft did find a closed, small but well defined circulation, and there has been a flareup in convection close to the center.
HURREVAC NHC TRACKING MAPS
Tropical Storm DON is currently under an area where shear is light. Albeit there is not a notable outflow channel, the upper pattern is somewhat divergent. Winds are light enough in that, it is allowing the system to focus its heat energy into more of a column, vice being spread out from strong shear. Based on the GFS wind shear forecast, a partial upper level anticyclone may develop over DON, and low shear is forecast to remain for the next 24-36 hours. Based on this, and SST’s of 29C, DON could continue to slowly strengthen tonight and on Tuesday. As the storm enters the Caribbean, an increase in westerly wind shear is forecast, which should begin to weaken the system. Given these parameters, I concur with the NHC current intensity forecast, however 18Z intensity models are in closer agreement, and while I do not believe DON will become a hurricane, I cannot totally rule out a stronger Tropical Storm than what NHC is indicating.
CURRENT WIND SHEAR MAP FROM CIMSS
GFS WIND SHEAR FORECAST
NHC INTENSITY FORECAST
INIT 17/2100Z 11.2N 52.6W 35 KT 40 MPH
12H 18/0600Z 11.5N 55.5W 40 KT 45 MPH
24H 18/1800Z 11.8N 58.9W 40 KT 45 MPH
36H 19/0600Z 12.0N 62.8W 40 KT 45 MPH
48H 19/1800Z 12.2N 67.0W 40 KT 45 MPH
DON continues to move to the west, being embedded in a strong east to west flow south of the subtropical ridge axis. Based on forecast steering maps and dynamic model guidance, I concur with the NHC forecast track, which lies close to the TVCA consensus model.
DYNAMIC MODEL TRACK GUIDANCE 18Z
The following are forecast 72 hour rainfall totals from the GFS and ECMWF
The following are current WATCHES and WARNINGS associated with Tropical Storm DON:
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY:
The government of Trinidad and Tobago has issued a Tropical Storm
Warning for Grenada.
The government of Barbados has issued a Tropical Storm Watch for
Barbados and for St. Vincent and the Grenadines.
The government of St. Lucia has issued a Tropical Storm Watch for
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Warning is in effect for…
A Tropical Storm Watch is in effect for…
* St. Vincent and the Grenadines
* St. Lucia
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, in this case in the
next 24 to 36 hours.
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, in this case in the next 24 to 36
Interests in Trinidad and Tobago, Aruba, Bonaire, and Curacao should
monitor the progress of Don.
For storm information specific to your area, please monitor
products issued by your national meteorological service.
Residents under these watch and warning areas should complete preparations for POSSIBLE FLOODING.
I should have another update sometime late tomorrow morning
Have a blessed evening!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST /SEVERE WEATHER SPECIALIST
MEMBER WEST CENTRAL FLORIDA AMS