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TROPICAL DEPRESSION NINE DISCUSSION NUMBER   1
NATIONAL WEATHER SERVICE MIAMI FL
11 PM EDT WED SEP 11 2002

AIR FORCE RECON FOUND A WELL-DEFINED WIND CENTER IN THE LOW PRESSURE
AREA OVER THE EAST-CENTRAL GULF WITH A CENTRAL PRESSURE OF 1001 MB.
PEAK 1500 FT FLIGHT-LEVEL WINDS WERE 40 KT WHICH EQUATES TO ABOUT 30
KT AT THE SURFACE.  LATER PASSES SHOWED SOMEWHAT LOWER WINDS...SO
THE CYCLONE IS CERTAINLY NOT STRENGTHENING AT THE MOMENT.  THE
SATELLITE SIGNATURE IS ALSO NOT IMPRESSIVE AT THIS TIME.  THERE IS
LITTLE DEEP CONVECTION NEAR THE CENTER AND THE CONVECTIVE BANDS
FARTHER SOUTH SHOW LITTLE CURVATURE.  WATER VAPOR IMAGERY DEPICTS A
MID- TO UPPER-LEVEL TROUGH AND DRY AIR IMPINGING ON THE WESTERN
PORTION OF THE DEPRESSION CIRCULATION.  NUMERICAL GUIDANCE SUGGESTS
THAT SOUTHWESTERLY SHEAR WILL BE AFFECTING THE SYSTEM DURING THE
FORECAST PERIOD.  THEREFORE THE OFFICIAL INTENSITY FORECAST DOES NOT
CALL FOR A LOT OF STRENGTHENING.

INITIAL MOTION IS ABOUT 035/4.  GLOBAL MODEL GUIDANCE INDICATES THAT 
THE STEERING CURRENTS WILL BE WEAK FOR THE NEXT COUPLE OF 
DAYS...WITH MID-LEVEL RIDGING TO THE SOUTHEAST AND WEST OF THE 
DEPRESSION.  A SLOW NORTH-NORTHEASTWARD MOTION IS LIKELY OVER THE 
NEXT COUPLE OF DAYS.  A LARGE 500 MB TROUGH IS FORECAST TO MOVE INTO 
THE CENTRAL U.S. AROUND THE END OF THE FORECAST PERIOD WHICH SHOULD 
INCREASE THE STEERING FLOW...AND POSSIBLY CARRY THE DEPRESSION 
INLAND BY 72 HOURS.  HOWEVER THERE IS A LOT OF UNCERTAINTY IN THE 
3-DAY FORECAST.

UNLESS THE DEPRESSION STALLS...A TROPICAL STORM WATCH WILL LIKELY BE 
NEEDED FOR A PORTION OF THE NORTHEAST GULF COAST TOMORROW.
 
FORECASTER PASCH
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     12/0300Z 26.5N  86.5W    30 KTS
12HR VT     12/1200Z 27.0N  86.1W    30 KTS
24HR VT     13/0000Z 27.5N  85.9W    35 KTS
36HR VT     13/1200Z 28.2N  85.6W    40 KTS
48HR VT     14/0000Z 29.0N  85.3W    45 KTS
72HR VT     15/0000Z 31.0N  84.5W    30 KTS...INLAND
 
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