| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

---

Tropical Storm TOMAS (Text)

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM TOMAS DISCUSSION NUMBER  23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL212010
500 PM EDT WED NOV 03 2010

AFTER STRUGGLING TO MAINTAIN ITS IDENTITY THIS MORNING...TOMAS HAS
RE-ORGANIZED DURING THE AFTERNOON.  AN AIR FORCE RESERVE HURRICANE
HUNTER AIRCRAFT HAS FOUND A BETTER-DEFINED CIRCULATION THAN WAS
PRESENT DURING THE PREVIOUS AIRCRAFT MISSION...ALTHOUGH THE LIGHT
AND VARIABLE WIND CENTER IS STILL RATHER LARGE.  THE PLANE FOUND
FLIGHT-LEVEL WINDS OF 48 KT BELOW 1500 FT AND ESTIMATED SURFACE
WINDS NEAR 40 KT FROM THE SFMR ABOUT 45 N MI EAST OF THE MEAN
CENTER.  THE MINIMUM CENTRAL PRESSURE WAS 1003 MB.  BASED ON THESE
DATA...TOMAS IS UPGRADED TO A 40-KT TROPICAL STORM.

WITH THE RE-FORMATION OF THE CENTER TO THE EAST OF THE PREVIOUS
ADVISORY POSITION...THE INITIAL MOTION IS NOW AN UNCERTAIN 335/5. 
A DEEP-LAYER TROUGH AND ACCOMPANYING COLD FRONT MOVING THROUGH THE
GULF OF MEXICO AND THE SOUTHEASTERN UNITED STATES SHOULD CAUSE
TOMAS TO RECURVE TOWARD THE NORTHEAST DURING THE NEXT 48 HR...WITH
A GENERALLY NORTHEASTWARD MOTION CONTINUING THROUGH 72-96 HR. 
THERE HAS BEEN A SIGNIFICANT CHANGE IN THE TRACK GUIDANCE SINCE THE
PREVIOUS ADVISORY...WITH THE LATEST MODEL RUNS IN GOOD AGREEMENT ON
A FASTER MOTION IN THE FIRST 72-96 HR.  INDEED THE NOGAPS...WHICH
PREVIOUSLY CALLED FOR TOMAS TO SHEAR APART AND TURN SOUTHWEST...
NOW CALLS FOR THE STORM TO MOVE STEADILY NORTHEASTWARD THROUGH THE
FORECAST PERIOD.  BASED ON THIS...THE NEW FORECAST TRACK IS FASTER
THAN THE PREVIOUS TRACK THROUGH 96 HR.  AFTER THAT TIME...THE
GUIDANCE REMAINS VERY DIVERGENT.  THE UKMET CONTINUES TO FORECAST
TOMAS TO SHEAR APART WITH THE LOW-LEVEL CIRCULATION MOVING
SOUTHWESTWARD...WHILE THE CANADIAN FORECAST TOMAS OR ITS
EXTRATROPICAL REMNANTS TO REACH NEWFOUNDLAND BY 120 HR.  THE OTHER
MODELS ARE IN BETWEEN THESE RATHER DRASTIC EXTREMES.  THE INTENSITY
FORECAST WILL FOLLOW THE SCENARIO OF THE PREVIOUS ADVISORY OF A
SLOW EASTWARD MOTION AFTER 96 HR AT A HIGHER LATITUDE THAN
PREVIOUSLY FORECAST.

NOW THAT TOMAS IS CONSOLIDATING...LIGHT VERTICAL WIND SHEAR AND WARM
SEA SURFACE TEMPERATURES FAVOR INTENSIFICATION.  THE SHIPS RAPID
INTENSIFICATION INDEX SHOWS A 50 PERCENT CHANCE OF 30 KT OF
STRENGTHENING DURING THE NEXT 24 HR...ALTHOUGH THE CURRENT
ORGANIZATION OF TOMAS ARGUES AGAINST THAT MUCH INTENSIFICATION. 
THE NEW INTENSITY FORECAST IS A COMPROMISE BETWEEN THE SHIPS AND
LGEM MODELS FOR THE FIRST 36-48 HR...CALLING FOR TOMAS TO
STRENGTHEN UNTIL LAND INTERACTION WITH HISPANIOLA BEGINS.  IT IS
NOT OUT OF THE QUESTION THAT TOMAS COULD BECOME A HURRICANE BEFORE
REACHING LAND AS FORECAST BY THE SHIPS AND GFDL MODELS.  AFTER
PASSING HISPANIOLA...INCREASING SOUTHWESTERLY WIND SHEAR IS
EXPECTED TO CAUSE TOMAS TO WEAKEN.  THE NEW INTENSITY FORECAST IS
AGAIN CLOSE TO BUT SLIGHTLY LOWER THAN THE INTENSITY CONSENSUS
MODEL ICON.
 
REGARDLESS OF THE EXACT TRACK AND INTENSITY OF TOMAS...THE TROPICAL
CYCLONE WILL POSE A SIGNIFICANT THREAT OF HEAVY RAINFALL...
FLOODING...AND POTENTIAL MUD SLIDES OVER HAITI AND THE DOMINICAN
REPUBLIC DURING THE NEXT FEW DAYS.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      03/2100Z 14.9N  74.8W    40 KT
 12HR VT     04/0600Z 15.8N  75.0W    45 KT
 24HR VT     04/1800Z 16.9N  75.0W    50 KT
 36HR VT     05/0600Z 18.4N  74.5W    55 KT
 48HR VT     05/1800Z 20.2N  73.2W    60 KT
 72HR VT     06/1800Z 23.5N  71.0W    60 KT
 96HR VT     07/1800Z 26.0N  69.0W    55 KT
120HR VT     08/1800Z 26.0N  67.0W    45 KT
 
$$
FORECASTER BEVEN
 
NNNN