000
AXNT20 KNHC 280453
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST THU DEC 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0415 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N12W 3N30W ACROSS THE EQUATOR NEAR 
42W. SCATTERED CLUSTERS OF SCATTERED MODERATE CONVECTION ARE S 
OF 8N ACROSS THE EQUATOR BETWEEN 23W-43W. 

...DISCUSSION...
GULF OF MEXICO...
UPPER RIDGE EXTENDS FROM E TEXAS NNE OVER THE UPPER MISSISSIPPI 
VALLEY. THE DEEP LAYERED TROUGH THAT HAS COVERED THE GULF OVER 
THE PAST FEW DAYS IS MOVING ACROSS FLORIDA INTO THE W ATLC NOW 
ONLY OVER THE E GULF E OF 87W LEAVING WESTERLY ZONAL WINDS IN 
ITS WAKE. DRY UPPER AIR AND STRONG SUBSIDENCE DOMINATE THE GULF 
WITH ONLY SCATTERED COLD AIR STRATOCUMULUS CLOUDS REMAINING THUS 
LEAVING THE GULF SHOWER FREE TONIGHT. MODERATE/STRONG SURFACE 
WINDS REMAIN ACROSS THE GULF WITH A SURFACE RIDGE OVER THE E US 
AND GULF INTO THE W ATLC. 
 
CARIBBEAN SEA...
DEEP LAYERED TROUGH OVER THE E GULF OF MEXICO COVERS THE W 
CARIBBEAN W OF 78W WITH THE COLD FRONT FROM THE W ATLC EXTENDING 
ACROSS E CUBA NEAR 21N76W TO NEAR 10N81W. SCATTERED SHOWERS AND 
POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 150 NM EITHER SIDE OF 
THE FRONT N OF 17N AND WITHIN 120 NM W OF THE FRONT ELSEWHERE. 
BROKEN COLD AIR STRATOCUMULUS CLOUDS COVER THE REMAINDER OF THE 
W CARIBBEAN. REMAINDER OF THE CARIBBEAN IS DOMINATED BY AN UPPER 
RIDGE THAT IS ANCHORED IN THE CENTRAL ATLC WITH DRY UPPER AIR 
AND STRONG SUBSIDENCE COVERING THE CARIBBEAN E OF 73W. STRONG 
EASTERLY TRADE WINDS REMAIN ACROSS THE AREA. 

ATLANTIC OCEAN...
THE DEEP LAYERED TROUGH OVER THE E US AND GULF OF MEXICO IS OVER 
THE FAR W ATLC W OF 70W WITH THE ASSOCIATED COLD FRONT EXTENDING 
THROUGH 32N62W TO ACROSS E CUBA NEAR 20N76W WHERE IT CONTINUES 
INTO THE CARIBBEAN. SCATTERED SHOWERS AND POSSIBLE ISOLATED 
THUNDERSTORMS ARE WITHIN 200 NM W OF THE FRONT. BROAD UPPER 
RIDGE IS ANCHORED IN THE CENTRAL ATLC NEAR 27N48W COVERING THE 
MOST OF THE ATLC W OF 35W. NARROW DEEP LAYERED TROUGH COVERS THE 
REMAINDER OF THE ATLC WITH THE MEAN AXIS EXTENDING THROUGH 
32N18W S ALONG 23N21W THEN SW TO 12N36W UNDERCUTTING THE BROAD 
UPPER RIDGE. ASSOCIATED COLD FRONT ENTERS THE REGION NEAR 32N19W 
SW TO 27N25W. SCATTERED SHOWERS ARE E OF THE FRONT TO 13W N OF 
27N INCLUDING THE CANARY ISLANDS. BROAD SURFACE RIDGE COVERS 
MUCH OF THE ATLC ANCHORED BY A 1026 MB HIGH NEAR 29N38W. 

$$
WALLACE