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Tropical Depression SERGIO (Text)

ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION SERGIO DISCUSSION NUMBER  27
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP212006
100 AM PST MON NOV 20 2006
 
THE LOW-LEVEL CENTER REMAINS MOSTLY EXPOSED WITH ALMOST ALL OF
THE DEEP CONVECTION WELL REMOVED TO THE EAST...BUT JUST CLOSE
ENOUGH TO YIELD DVORAK T NUMBERS OF 2.0 AT 0600 UTC.  VERY RECENTLY
A LITTLE CONVECTION HAS INCREASED NEAR THE CENTER.  AN EARLIER
QUIKSCAT OVERPASS AT 0122 UTC SHOWED A FEW 30-KT VECTORS NEAR THE
CENTER AND STRONGER BUT RAIN-INFLATED VECTORS IN THE CONVECTION. 
THESE DATA SUPPORT KEEPING THE ADVISORY INTENSITY AT 30 KT. 
GRADUAL WEAKENING IS INDICATED IN ACCORDANCE WILL ALL INTENSITY
FORECAST GUIDANCE DUE TO PERSISTENT WEST-SOUTHWESTERLY SHEAR.  THE
OFFICIAL FORECAST CALLS FOR SERGIO TO REMAIN A TROPICAL CYCLONE FOR
ONLY ABOUT 24 MORE HOURS...BUT ONE CANNOT BE SURE JUST HOW STUBBORN
THIS SYSTEM WILL BE IN GIVING UP ITS DEEP CONVECTION.
 
IT HAS NOT BEEN HARD TO FIND THE CENTER...WHICH HAS BEEN MOVING
ABOUT 250/4 FOR THE PAST SEVERAL HOURS...BUT PERHAPS MORE WESTERLY
THAN THAT RECENTLY.  AS A LOW- TO MID-LEVEL RIDGE BUILDS EASTWARD
TO THE NORTH OF THE CYCLONE...A GENERAL SLOW WESTWARD MOTION IS
FORECAST...WITH A SLIGHT INCREASE IN FORWARD SPEED BEYOND ABOUT 24
HOURS PRESUMING THE REMNANT LOW WILL NO LONGER BE HINDERED BY THE
UPPER-LEVEL WESTERLIES PUSHING AGAINST THE DEEP CONVECTION.  THE
NEW OFFICIAL TRACK FORECAST IS VERY SIMILAR TO THE PREVIOUS
ONE...CALLING FOR DISSIPATION OF THE REMNANT LOW BY 72 HOURS.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      20/0900Z 14.8N 106.7W    30 KT
 12HR VT     20/1800Z 14.8N 107.3W    30 KT
 24HR VT     21/0600Z 14.9N 108.1W    25 KT
 36HR VT     21/1800Z 15.1N 109.2W    25 KT...REMNANT LOW
 48HR VT     22/0600Z 15.4N 110.6W    20 KT...REMNANT LOW
 72HR VT     23/0600Z...DISSIPATED
 
$$
FORECASTER KNABB
 
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