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Tropical Storm LISA (Text)

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TROPICAL STORM LISA DISCUSSION NUMBER   9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL142010
1100 PM AST WED SEP 22 2010
 
LISA HAS CHANGED LITTLE IN ORGANIZATION DURING THE LAST SEVERAL
HOURS.  DEEP CONVECTION REMAINS CONFINED TO A SMALL AREA NEAR THE
CENTER AND IN A BAND OVER THE NORTHEASTERN PORTION OF THE
CIRCULATION.  A 2340 UTC ASCAT PASS SHOWED MAXIMUM WINDS NEAR 30 KT
OVER THE NORTHERN SEMICIRCLE.  THE INITIAL WIND SPEED ESTIMATE IS
LOWERED TO 35 KT...AND THIS MIGHT BE GENEROUS.  LISA COULD
STRENGTHEN DURING THE NEXT COUPLE OF DAYS AS IT REMAINS OVER
MARGINALLY WARM WATER AND IN LOW WIND SHEAR ENVIRONMENT.  AFTER
THAT TIME...WESTERLY SHEAR IS ANTICIPATED TO INCREASE SIGNIFICANTLY
AND THAT SHOULD PROMOTE STEADY WEAKENING.
 
LISA HAS BEEN MOVING EASTWARD SINCE THE LAST ADVISORY...AND THE
INITIAL MOTION ESTIMATE IS 090/4.  THE TROPICAL CYCLONE WILL LIKELY
CONTINUE TO MEANDER FOR THE NEXT 12 TO 24 HOURS AS IT REMAINS
CAUGHT IN WEAK STEERING CURRENTS NEAR THE BASE OF A SHARP
DEEP-LAYER TROUGH OVER THE EASTERN ATLANTIC.  A TURN TO THE
NORTHWEST WITH A GRADUAL INCREASE IN FORWARD SPEED IS FORECAST
BEYOND 24 HOURS AS THE TROUGH CUTS-OFF AND SOME RIDGING DEVELOPS
TO THE NORTHEAST OF THE CYCLONE.  THE OFFICIAL TRACK FORECAST IS
ADJUSTED A LITTLE TO THE RIGHT OF THE PREVIOUS ONE...DUE TO THE
INITIAL POSITION AND MOTION AND TO BE IN BETTER AGREEMENT WITH
THE LATEST GUIDANCE.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      23/0300Z 17.7N  29.6W    35 KT
 12HR VT     23/1200Z 17.8N  29.5W    35 KT
 24HR VT     24/0000Z 18.0N  29.8W    40 KT
 36HR VT     24/1200Z 18.4N  30.3W    45 KT
 48HR VT     25/0000Z 19.1N  31.0W    45 KT
 72HR VT     26/0000Z 21.0N  32.5W    45 KT
 96HR VT     27/0000Z 23.0N  35.0W    40 KT
120HR VT     28/0000Z 25.5N  38.0W    30 KT
 
$$
FORECASTER CANGIALOSI
 
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