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ZCZC MIATCDAT5 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION KATRINA DISCUSSION NUMBER 10 NATIONAL WEATHER SERVICE MIAMI FL 11 PM EDT SAT OCT 30 1999

KATRINA HAS PULLED A HALLOWEEN TRICK. SATELLITE IMAGERY AND SURFACE OBSERVATIONS DURING THE AFTERNOON INDICATED THE CIRCULATION WAS ELONGATED FROM THE SOUTHWEST GULF OF MEXICO SOUTHEASTWARD TO NORTHERN NICARAGUA. OBSERVATIONS FROM LA CEIBA AND ROATAN IN HONDURAS HAVE SHOWN PERSISTENT SOUTHWESTERLY WINDS...INDICATING THE CENTER HAS RE-FORMED OF THE GULF OF HONDURAS. THIS REQUIRES A RE- LOCATION FROM THE PREVIOUS PACKAGE.

WITH THE REFORMATION...THE INITIAL MOTION IS AT BEST A GUESS AND IS SET TO 305/9. THE HURRICANE GUIDANCE REMAINS DIVERGENT...WITH THE BAMS TAKING KATRINA TO THE PACIFIC IN 72 HOURS AND THE BAMD TAKING IT TO THE FLORIDA KEYS. THE DEEP LAYER LOW OVER THE WESTERN GULF STATES IS FORECAST TO MOVE EAST BY ALL LARGE SCALE GUIDANCE...AND THIS SHOULD RECURVE KATRINA TO THE NORTH AND NORTHEAST. THE OFFICIAL FORECAST REFLECT THIS...AND IS SHIFTED NORTH AND EAST OF THE PREVIOUS FORECAST. LARGE SCALE GUIDANCE SUGGESTS THE 72 HOUR POINT MAY NOT BE FAR ENOUGH EAST...BUT THERE IS ALREADY SO A LARGE CHANGE FROM THE PREVIOUS ADVISORY THAT I AM RELUCTANT TO CHANGE IT FURTHER.

SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB ARE 30 KT AND 25 KT RESPECTIVELY...WITH THE CENTRAL CONVECTION RATHER POORLY ORGANIZED. THUS...THE INITIAL INTENSITY REMAINS 25 KT. SINCE SOME EASTERLY SHEAR REMAINS...ONLY MODEST STRENGTHENING IS FORECAST BEFORE THE CENTER MOVES OVER THE YUCATAN PENINSULA. AFTER THAT...THE FORECAST IS COMPLEX. THE AVN AND NOGAPS MODELS DEVELOP A LOW OVER THE NORTHEASTERN GULF OF MEXICO THAT APPEARS RELATED TO THE DEEP LAYER TROUGH. SHOULD THIS VERIFY...IT WOULD LIKELY ABSORB KATRINA. THE CYCLONE COULD ALSO BECOME EXTRATROPICAL AND BECOME THE FOCUS OF THE DEVELOPMENT OVER THE NORTHEAST GULF. THERE IS ALSO AN OUTSIDE CHANCE THAT KATRINA COULD REGAIN TROPICAL STORM STATUS AS IT LEAVES THE YUCATAN PENINSULA. THE LOW CONFIDENCE INTENSITY FORECAST IS FOR KATRINA TO SURVIVE AS A 30 KT DEPRESSION THROUGH 72 HOURS.

A SPECIAL THANKS GOES TO THE METEOROLOGICAL SERVICE OF HONDURAS FOR SENDING VALUABLE OBSERVATIONS VIA FAX AFTER NORMAL COMMUNICATIONS HAD BROKEN DOWN.

BEVEN

FORECAST POSITIONS AND MAX WINDS

INITIAL 31/0300Z 16.9N 87.2W 25 KTS 12HR VT 31/1200Z 17.9N 88.1W 30 KTS 24HR VT 01/0000Z 19.4N 88.5W 25 KTS...INLAND 36HR VT 01/1200Z 21.2N 88.3W 25 KTS...INLAND 48HR VT 02/0000Z 23.5N 87.5W 30 KTS 72HR VT 03/0000Z 28.0N 84.0W 30 KTS

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