[Tropical] Tropical Cyclone Discussion

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WTNT42 KNHC 131435
TCDAT2
TROPICAL STORM BERTHA DISCUSSION NUMBER  42
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL022008
1100 AM EDT SUN JUL 13 2008

SATELLITE IMAGES INDICATE THAT MOST OF THE DEEP CONVECTION
ASSOCIATED WITH BERTHA HAS DECREASED EXCEPT WITHIN A BAND TO THE
NORTH OF THE CENTER. HOWEVER...BERTHA STILL HAS A LARGE AND
VIGOROUS LOW LEVEL CIRCULATION.  INITIAL INTENSITY IS SET AT 55
KNOTS AND A RECONNAISSANCE PLANE WILL GIVE US ADDITIONAL INTENSITY
AND WIND RADII INFORMATION LATER TODAY. SHEAR AND COOL WATER SHOULD
INDUCE WEAKENING...BUT MOST OF THE GLOBAL AND INTENSITY MODELS
EITHER STRENGTHEN OR KEEP BERTHA WITH THE SAME INTENSITY. THE
OFFICIAL FORECAST HAS OPTED FOR AN INITIAL WEAKENING AND THEN
FOLLOWS THE SHIPS MODELS CALLING FOR NO CHANGE IN INTENSITY.

BERTHA HAS BEEN MEANDERING FOR THE PAST 24 HOURS OR SO...BUT NOW
APPEARS TO BE MOVING TOWARD THE NORTHWEST OR 320 DEGREES AT ABOUT 2
TO 3 KNOTS. AS THE SUBTROPICAL RIDGE DEVELOPS AND A TROUGH
APPROACHES...THE CYCLONE SHOULD CONTINUE TO MOVE ON A SLOW
NORTHWESTERLY AND THEN NORTHERLY TRACK FOR A COUPLE OF DAYS.
THEREAFTER...THE CYCLONE IS EXPECTED TO BE EMBEDDED WITHIN THE
MID-LATITUDE WESTERLIES AND BE STEERED SLOWLY EASTWARD.
HOWEVER...THIS PROCESS WILL SLOW AND TROPICAL CYCLONE BERTHA COULD
BE WITH US FOR SEVERAL MORE DAYS AS INDICATED BY GLOBAL MODELS.


FORECAST POSITIONS AND MAX WINDS

INITIAL      13/1500Z 30.2N  63.0W    55 KT
 12HR VT     14/0000Z 30.4N  63.0W    50 KT
 24HR VT     14/1200Z 31.5N  63.5W    50 KT
 36HR VT     15/0000Z 33.0N  63.6W    50 KT
 48HR VT     15/1200Z 34.5N  63.0W    50 KT
 72HR VT     16/1200Z 36.0N  61.0W    50 KT
 96HR VT     17/1200Z 36.0N  58.0W    50 KT
120HR VT     18/1200Z 35.0N  54.0W    50 KT

$$
FORECASTER AVILA
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