03Z Tropical Update

TROPICAL DEPRESSION 4 FORECAST #2
TROPICAL FORECAST CENTER
10:31 PM EDT MONDAY AUGUST 2, 2010

AT 11:00 PM EDT/0300Z...THE CENTER OF TROPICAL DEPRESSION 4 WAS LOCATED NEAR 13.6 N 45.1 W OR ABOUT 1090 MILES EAST OF THE LESSER ANTILLES. THE DEPRESSION WAS MOVING TOWARDS THE WEST-NORTHWEST NEAR 23 MPH...AND THIS MOTION IS EXPECTED TO CONTINUE WITH A GRADUAL INCREASE IN FORWARD SPEED DURING THE NEXT 24 HOURS. MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...AND THE DEPRESSION IS EXPECTED TO BECOME A TROPICAL STORM ON TUESDAY. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB/29.74 IN.

DURING THE COURSE OF THE PAST 6 HOURS...THE DEPRESSION IS LOOKING BETTER ORGANIZED STRUCTURE WISE...BUT CAN/T GET ANY DEEP CONVECTION TO DEVELOP WHICH WOULD REALLY MAKE THIS STORM STRONGER THAT WHAT IT COULD BE. DVORAK...ADT...AND MIMIC-IR ESTIMATES ALL SHOW THAT THIS IS CLOSE TO TROPICAL STORM STRENGTH BUT I BELIEVE THAT THIS SYSTEM NEEDS SOME DEEPER THUNDERSTORMS FOR THIS TO HAPPEN AND WITH IT/S FAST MOTION I/M SUSPECTING THAT THIS WILL KEEP THE DEPRESSION FOR DEVELOPING DEEP THUNDERSTORMS...SO WITH ALL THAT IN MIND...INITIAL INTENSITY REMAINS AT 30 KTS. CONDITIONS DO REMAIN FAVORABLE FOR THIS SYSTEM TO BECOME A TROPICAL STORM WITHIN THE NEXT 12 HOURS. ALSO FROM THE PREVIOUS FORECASTS...I/M NOT SHOWING WEAKENING AS I HAD WITH THE PREVIOUS FORECAST...DUE TO THE SHIPS MODEL ARE NOT SHOWING THE SHEAR AS STRONG AS IT DID EARLIER...BUT I/M STILL KEEPING THIS SYSTEM SHORT OF HURRICANE STRENGTH. MY INTENSITY FORECAST IS A SLIGHT CHANGE FROM THE PREVIOUS FORECAST I STILL HAVE THE SYSTEM PEAKING AT 60 KTS DURING THE FORECAST PERIOD...BUT I DON/T HAVE ANY WEAKENING AS I DID DURING MY PREVIOUS FORECAST...BUT THIS REMAINS STRONGER THAN NHCs INTENSITY FORECAST DUE TO I DON/T SEE THE SHEAR AS STRONG AS IT INDICATED EARLIER.

INITIAL MOTION IS A SWIFT 285/20. THE DEPRESSION IS BEING STEERED BY A SUBTROPICAL HIGH LOCATED NORTH OF THE STORM AND THIS WILL BE THE GENERAL MOTION THAT THIS SYSTEM WILL TAKE OVER THE NEXT FEW DAYS. FORECAST MODELS DIVEREGE BEYOND AROUND THE 48 TO 72 HOUR MARK WHERE THERE ARE TWO SCENARIOS THAT COULD PLAY OUT IN THE EVENTUAL TRACK OF THE DEPRESSION. ONE IS WHERE IT GETS CAUGHT UP BY A COLD FRONT THAT IS EXPECTED TO MOVE OFF THE COAST TOWARDS DAYS 4 AND 5 AND RECURVE OUT TO SEA...POSSIBLY AFFECTING BERMUDA BY THE WEEKEND OR EARLY NEXT WEEK AS MUST MODELS ARE BEGINNING TO INDICATE OR THE DEPRESSION GET CAUGHT IN A WEAKNESS IN STEERING PATTERN AND THE SYSTEM SLOWS DOWN IN FORWARD SPEED TOWARDS DAYS 4 AND 5 AND POSSIBLY INCREASING THE THREAT TO THE SOUTHEAST U.S. BY EARLY NEXT WEEK. I HAVE BEEN GOING WITH THIS POSSIBILITY FOR THE LAST FORECAST AND I/M GOING TO STICK WITH IT FOR THIS FORECAST UPDATE. OVERALL MY FORECAST TRACK IS SLOWER AND A LITTLE NORTHWEST OF MY PREVIOUS FORECAST TRACK AND SOUTH OF NHCs FORECAST TRACK.

TRACK AND INTENSITY FORECAST

03/03Z 13.6 N 45.1 W 30 KTS
03/15Z 14.4 N 47.7 W 35 KTS
04/03Z 15.9 N 51.5 W 40 KTS
04/15Z 17.4 N 55.1 W 45 KTS
05/03Z 19.0 N 58.1 W 55 KTS
06/03Z 22.0 N 63.0 W 60 KTS
07/03Z 24.0 N 65.5 W 60 KTS
08/03Z 26.5 N 68.5 W 60 KTS

JACKSON