[Tropical] Tropical Cyclone Discussion

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WTNT44 KNHC 210251
TCDAT4
TROPICAL STORM DOLLY DISCUSSION NUMBER   3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL042008
1100 PM EDT SUN JUL 20 2008

DATA FROM A NOAA P3 AIRCRAFT INDICATE THAT DOLLY HAS NOT BECOME ANY
BETTER ORGANIZED THIS EVENING.  INDEED...THE SYSTEM PROBABLY
DOESN'T HAVE A CLOSED SURFACE CENTER RIGHT NOW.  HOWEVER...DOLLY IS
MAINTAINING VIGOROUS CONVECTION AND THE STRONGEST WINDS...AS
ESTIMATED BY THE SFMR...HAVE INCREASED TO 45 KT.  SINCE DOLLY COULD
REGENERATE A CENTER AT ANY TIME...NO GOOD WOULD BE SERVED BY
HANGING ON A TECHNICALITY.

THE INITIAL MOTION REMAINS 305/12.  GUIDANCE SUGGESTS A TEMPORARY
INCREASE IN FORWARD SPEED...PERHAPS DUE TO THE UPPER LOW TO THE
WEST OF DOLLY MOVING SOUTHWESTWARD...ENHANCING THE DEEP LAYER
EASTERLIES.  DOLLY SHOULD CONTINUE TOWARD THE WEST-NORTHWEST SOUTH
OF A MID-LEVEL RIDGE OVER TEXAS.  BY 72 HOURS...THIS RIDGE
WEAKENS...AND SOME OF THE GUIDANCE SHOWS A SLIGHT NORTHWARD TURN IN
THE WESTERN GULF.  THE OFFICIAL FORECAST SHOWS MORE OF A STRAIGHT
LINE TRACK BUT IS STILL VERY CLOSE TO THE CONSENSUS OF A VERY
TIGHTLY PACKED GUIDANCE ENVELOPE.

SHEAR ASSOCIATED WITH THE UPPER LOW MAY BE KEEPING DOLLY FROM
ORGANIZING FOR NOW...BUT THIS SHOULD RAPIDLY BECOME A NON-FACTOR.
ONCE THE SYSTEM ENTERS THE GULF OF MEXICO...ALL GLOBAL GUIDANCE
SUGGESTS A VERY FAVORABLE ENVIRONMENT FOR STRENGTHENING...WITH A
LARGE ANTICYCLONE ALOFT...NO SHEAR...AND WARM GULF WATERS.  THE
QUANTITATIVE GUIDANCE IS IN PRETTY GOOD AGREEMENT AND THE OFFICIAL
FORECAST BLENDS THE LGEM...SHIPS...AND GFDL.  THE INTENSITY
FORECAST ASSUMES THAT THERE WILL BE SOME DISRUPTION OF THE SYSTEM
OVER THE YUCATAN...WHICH COULD BE AVOIDED IF A CENTER REFORMS TO
THE NORTH WITHIN THE DEEP CONVECTION.  INTERESTS IN THE WESTERN
GULF OF MEXICO SHOULD MONITOR THE PROGRESS OF DOLLY.


FORECAST POSITIONS AND MAX WINDS

INITIAL      21/0300Z 19.6N  85.8W    45 KT
 12HR VT     21/1200Z 20.9N  88.1W    45 KT...INLAND
 24HR VT     22/0000Z 22.3N  90.8W    50 KT
 36HR VT     22/1200Z 23.4N  92.9W    55 KT
 48HR VT     23/0000Z 24.3N  94.5W    65 KT
 72HR VT     24/0000Z 25.5N  97.0W    75 KT
 96HR VT     25/0000Z 27.0N 100.0W    30 KT...INLAND
120HR VT     26/0000Z...DISSIPATED

$$
FORECASTER FRANKLIN



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