358
WTNT45 KNHC 272034
TCDAT5
TROPICAL STORM TAMMY DISCUSSION NUMBER 34
NWS NATIONAL HURRICANE CENTER MIAMI FL AL202023
500 PM AST FRI OCT 27 2023
TAMMY'S CLOUD PATTERN HASN'T CHANGED MUCH ON SATELLITE IMAGES SINCE
EARLIER TODAY. THERE HAS BEEN SOME COOLING OF THE CONVECTIVE CLOUD
TOPS TO ABOUT -60 DEG C NEAR THE CENTER OF CIRCULATION ALONG WITH A
FEW BANDING FEATURES. THERE IS LIMITED UPPER-LEVEL OUTFLOW TO THE
SOUTH AND EAST OF THE SYSTEM. THE CURRENT INTENSITY IS HELD AT 55
KT IN AGREEMENT WITH AN OBJECTIVE ADT DVORAK ESTIMATE FROM UW-CIMSS.
TAMMY IS CURRENTLY SITUATED OVER SSTS OF AROUND 25 DEG C IN A
MARGINALLY MOIST MID-LEVEL AIR MASS. THE DYNAMICAL GUIDANCE
INDICATES A SIGNIFICANT INCREASE IN VERTICAL WIND SHEAR DURING THE
NEXT DAY OR SO. THIS SHOULD CAUSE A GRADUAL WEAKENING TREND TO
COMMENCE SOON. LATER IN THE FORECAST PERIOD, ALTHOUGH THE OCEAN
WATERS UNDER TAMMY SHOULD GET A LITTLE WARMER, STRONG SHEAR AND
SUBSTANTIALLY DRIER AIR SHOULD CAUSE CONTINUED WEAKENING. THE
OFFICIAL INTENSITY FORECAST IS ABOVE MOST OF THE MODEL GUIDANCE, SO
TAMMY COULD WEAKEN TO A DEPRESSION SOONER THAN SHOWN HERE.
TAMMY IS CURRENTLY MOVING SLOWLY NORTHWESTWARD AT ABOUT 320/3
KT. THE CYCLONE SHOULD SOON TURN TO AN EASTWARD TRACK AND MOVE
ALONG THE NORTHERN SIDE OF A SUBTROPICAL RIDGE FOR A COUPLE OF
DAYS. LATER IN THE FORECAST PERIOD, TAMMY IS EXPECTED TO TURN
SOUTHWARD AND MOVE ALONG THE EASTERN SIDE OF A MID-LEVEL HIGH. THE
OFFICIAL TRACK FORECAST LIES BETWEEN THE SIMPLE AND CORRECTED
DYNAMICAL MODEL CONSENSUS SOLUTIONS.
FORECAST POSITIONS AND MAX WINDS
INIT 27/2100Z 32.5N 61.4W 55 KT 65 MPH
12H 28/0600Z 32.7N 60.8W 50 KT 60 MPH
24H 28/1800Z 32.7N 59.0W 50 KT 60 MPH
36H 29/0600Z 32.3N 56.2W 45 KT 50 MPH
48H 29/1800Z 31.2N 53.4W 40 KT 45 MPH
60H 30/0600Z 30.0N 51.5W 35 KT 40 MPH
72H 30/1800Z 28.5N 51.0W 30 KT 35 MPH
96H 31/1800Z 28.0N 51.4W 25 KT 30 MPH
120H 01/1800Z 27.5N 52.0W 25 KT 30 MPH
FORECASTER PASCH
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page