000
AXNT20 KNHC 281757
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST TUE NOV 28 2006

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...
CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...
NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC
OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N.
THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...
METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

...THE ITCZ...
9N11W 7N20W 7N30W 5N42W 4N50W 3N55W. ISOLATED MODERATE SHOWERS 
TO LOCALLY STRONG THUNDERSTORMS ARE WITHIN 120 TO 180 NM ON 
EITHER SIDE OF THE AXIS EAST OF 30W. SCATTERED MODERATE SHOWERS 
TO ISOLATED STRONG THUNDERSTORMS ARE WITHIN 240 NM ON EITHER 
SIDE OF THE AXIS BETWEEN 30W AND 40W...AND WITHIN 120 NM TO
THE NORTH OF THE AXIS WEST OF 40W. THE WIDELY SCATTERED TO 
SCATTERED MODERATE SHOWERS AND ISOLATED STRONG THUNDERSTORMS
FROM 6N TO 11N BETWEEN 58W AND 62W FROM NORTHERN COASTAL GUYANA 
TO TRINIDAD ARE OCCURRING IN AN AREA OF ONSHORE TRADEWIND FLOW
COMBINED WITH UPPER LEVEL DIFFLUENT FLOW.

...DISCUSSION...
THE GULF OF MEXICO...
AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTER IS OVER CENTRAL 
FLORIDA NEAR 28N81W. AN UPPER LEVEL RIDGE GOES FROM THE ISTHMUS 
OF TEHUANTEPEC OF MEXICO THROUGH THE CENTER BEYOND 34N78W.
DRY AIR IS EVERYWHERE IN THE GULF OF MEXICO. UPPER LEVEL 
MOISTURE IS BEING CARRIED NORTHEASTWARD FROM MEXICO NEAR 
20N100W...ALONG THE TEXAS GULF COAST...BEYOND LOUISIANA.
SURFACE ANTICYCLONIC FLOW IS EVERYWHERE.

THE CARIBBEAN SEA...
THE NORTHWESTERN CORNER OF THE AREA IS COVERED BY UPPER LEVEL 
ANTICYCLONIC FLOW...ASSOCIATED WITH THE CENTRAL FLORIDA 
ANTICYCLONIC CIRCULATION CENTER. A MIDDLE TO UPPER LEVEL TROUGH
ENTERS THE AREA THROUGH THE WINDWARD PASSAGE...DROPPING 
SOUTHWESTWARD TO 15N80W...AND MAYBE EVEN THE BORDER OF EASTERN 
HONDURAS/NORTHERN NICARAGUA. AN ATLANTIC OCEAN COLD FRONT PASSES 
THROUGH 32N45W TO 27N50W TO 20N60W. A DISSIPATING COLD FRONT 
GOES FROM 20N60W TO 19N65W JUST NORTH OF PUERTO RICO...TO THE 
EASTERN DOMINICAN REPUBLIC NEAR 19N69W. ISOLATED MODERATE 
SHOWERS AND POSSIBLE THUNDERSTORMS ARE NORTH OF 18N BETWEEN 60W 
AND 70W...LEADING AWAY FROM THE AREA INTO THE ATLANTIC OCEAN. 
EXTREMELY DRY AIR IS WITHIN 60 TO 75 NM ON EITHER SIDE OF
25N62W 22N70W 21N77W 19N80W 18N86W. SCATTERED MODERATE SHOWERS 
TO ISOLATED STRONG THUNDERSTORMS ARE SOUTH OF 15N83W 12N80W 
11N76W IN THE SOUTHWESTERN CORNER OF THE AREA. THE CLOUD TOP 
TEMPERATURES IN THE PRECIPITATION SOUTH OF 12N BETWEEN 75W
AND 82W HAVE BEEN WARMING DURING THE LAST FIVE HOURS AS THE 
CONVECTIVE ACTIVITY HAS WEAKENED COMPARATIVELY. THIS MAY BE 
DIURNAL CONVECTIVE PRECIPITATION...IN BROAD SURFACE LOW 
PRESSURE...ENHANCED BY UPPER LEVEL DIFFLUENT FLOW.
UPPER LEVEL EASTERLY FLOW IS ON THE SOUTHERN SIDE
OF THE ATLANTIC OCEAN-TO-CARIBBEAN SEA TROUGH.

THE ATLANTIC OCEAN...
A DEEP LAYER TROUGH PASSES THROUGH 32N50W TO 24N60W THROUGH
THE WINDWARD PASSAGE...INTO THE CARIBBEAN SEA. AN ATLANTIC
OCEAN COLD FRONT PASSES THROUGH 32N45W TO 27N50W TO 20N60W.
A DISSIPATING COLD FRONT GOES FROM 20N60W TO 19N65W JUST NORTH 
OF PUERTO RICO...TO THE EASTERN DOMINICAN REPUBLIC NEAR 19N69W.
BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED MODERATE 
SHOWERS/LOCALLY STRONG THUNDERSTORMS ARE WITHIN 180 NM ON 
EITHER  SIDE OF 20N63W 23N55W 27N45W BEYOND 32N40W. SURFACE
ANTICYCLONIC FLOW IS WEST OF THE COLD FRONT. A MIDDLE TO UPPER 
LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 12N48W. A MIDDLE TO 
UPPER LEVEL TROUGH IS DROPPING SOUTHWARD ALONG THE COAST OF 
MOROCCO. ONE POSSIBLE MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION 
MAY BE FORMING ABOUT 75 NM NORTH OF THE CAPE VERDE ISLANDS...
AND ANOTHER ONE IS NEAR 17N35W.
 
$$
MT