000
WTNT42 KNHC 150426
TCDAT2
TROPICAL DEPRESSION TWO SPECIAL DISCUSSION NUMBER  12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL022009
1230 AM AST SAT AUG 15 2009
 
SATELLITE IMAGERY INDICATES THAT THE REMNANT CIRCULATION OF TROPICAL
DEPRESSION TWO HAS REGENERATED INTO A TROPICAL CYCLONE. DATA FROM
A NOAA G-IV MISSION...NOAA BUOY 41041...AND A RECENTLY-RECEIVED
ASCAT PASS INDICATES THAT THE CIRCULATION IS WELL-DEFINED. THE BUOY
ALSO REPORTED 1006.4 MB AND NORTH-NORTHWEST WINDS OF 19 KT. 
ORGANIZED CONVECTION HAS NOW PERSISTED NEAR THE CENTER LONG
ENOUGH TO CONSIDER THIS SYSTEM A TROPICAL DEPRESSION. THE INITIAL
INTENSITY IS SET TO 30 KT...IN AGREEMENT WITH A SPECIAL DVORAK
CLASSIFICATION FROM TAFB AND WINDS FROM ASCAT.
 
THE INITIAL MOTION ESTIMATE IS 270/13. THE GLOBAL MODELS ARE IN
AGREEMENT THAT DEEP LAYER RIDGING WILL PERSIST NORTH OF THE
TROPICAL CYCLONE FOR THE NEXT SEVERAL DAYS...WHICH SHOULD STEER THE
SYSTEM IN A WEST OR WEST-NORTHWESTWARD DIRECTION.  IN A FEW
DAYS...THE CYCLONE WILL BE APPROACHING THE WESTERN PERIPHERY OF THE
SUBTROPICAL RIDGE TO NORTH...WHICH COULD ALLOW THE SYSTEM TO MOVE
MORE TOWARD THE NORTHWEST. FOR SUCH A WEAK SYSTEM...THE TRACK
GUIDANCE IS IN GOOD AGREEMENT THROUGH THE PERIOD...AND THE OFFICIAL
FORECAST IS CLOSE TO THE MULTI-MODEL CONSENSUS. HOWEVER...NOW THAT
THE SYSTEM IS BEING INITIALIZED AS A TROPICAL CYCLONE IN MOST OF
THE GLOBAL MODEL FIELDS...IT WOULD NOT BE SURPRISING TO SEE CHANGES
IN THE GUIDANCE DURING THE NEXT COUPLE OF GUIDANCE CYCLES.
 
RELATIVELY LOW SHEAR IS FORECAST BY THE SHIPS MODEL FOR THE NEXT DAY
OR SO WHILE THE SYSTEM REMAINS UNDER THE SOUTHWEST PORTION OF AN
UPPER HIGH OVER THE CENTRAL ATLANTIC.  THEREAFTER...AN UPPER TROUGH
TO THE NORTHWEST OF THE TROPICAL CYCLONE COULD INDUCE SOME WESTERLY
SHEAR.  GIVEN THIS...THE INTENSITY FORECAST ONLY SHOWS SLOW
INTENSIFICATION THOUGH 48 HOURS AND LITTLE CHANGE AFTER THAT.  THE
OFFICIAL FORECAST IS CLOSE TO A BLEND OF THE SHIPS/LGEM/HWRF
MODELS. HOWEVER...IT IS WORTH NOTING THAT THE INTENSITY PROBABILITY
TABLE SHOWS ABOUT A 25 PERCENT CHANCE THAT THIS SYSTEM COULD BE A
HURRICANE AFTER 48 HOURS.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      15/0430Z 14.6N  45.8W    30 KT
 12HR VT     15/1200Z 14.7N  47.6W    30 KT
 24HR VT     16/0000Z 15.0N  51.0W    40 KT
 36HR VT     16/1200Z 16.0N  54.5W    45 KT
 48HR VT     17/0000Z 17.0N  58.0W    50 KT
 72HR VT     18/0000Z 19.5N  65.0W    50 KT
 96HR VT     19/0000Z 22.0N  71.0W    50 KT
120HR VT     20/0000Z 25.5N  76.5W    50 KT
 
$$
FORECASTER BLAKE/BRENNAN