000
AXNT20 KNHC 171657
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SAT FEB 17 2007

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 
1615 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 7N10W 4N18W 3N31W CROSSING THE 
EQUATOR SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 
120 NM OF THE AXIS FROM 30W-43W. CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION ARE FROM THE EQUATOR TO THE 
ITCZ AXIS BETWEEN 10W-23W.
 
...DISCUSSION...
GULF OF MEXICO...
THE COLD FRONT THAT EXITED THE GULF YESTERDAY COMBINED WITH THE 
1024 MB HIGH NOW ANCHORED OVER THE CENTRAL GULF IS GIVING THE 
ENTIRE AREA CLEAR SKIES WITH SOME OF THE COOLEST TEMPERATURES OF 
THE SEASON...ESPECIALLY OVER FLORIDA. HOWEVER...A FAST MOVING 
COLD FRONT IS ALONG THE TEXAS COAST AT 17/1500 UTC AND WILL 
CONTINUE ACROSS THE AREA EXITING ON SUN MORNING. THIS SECOND 
FRONT IS EMBEDDED WITHIN DRY AIR...THUS LITTLE IN THE FORM OF 
SHOWERS IS EXPECTED BUT WILL KEEP TEMPERATURES FROM RECOVERING.  
OVERCAST LOW/MID CLOUDS ARE OVER THE SW GULF AS RETURN FLOW IS 
ESTABLISHED AROUND THE SURFACE HIGH. IN THE UPPER LEVELS...VERY 
BROAD UPPER TROUGH COVERS THE N GULF AND EXTENDS FROM THE W ATLC 
TO THE CENTRAL PLAIN STATES SETTING UP WESTERLY UPPER FLOW 
ACROSS THE GULF. THE SUBTROPICAL JET REMAINS CENTERED ACROSS 
THE N GULF WITH WINDS OF 90 TO 130 KT COVERING THE GULF N OF 
23N. 
   
CARIBBEAN SEA...
A COLD FRONT THAT EXTENDS FROM THE W ATLC CROSSES CUBA NEAR 
20N76W BECOMING NEAR STATIONARY JUST E OF THE CAYMAN ISLANDS TO 
NE HONDURAS. BROKEN/OVERCAST LOW/MID LEVEL CLOUDS WITH POSSIBLE 
ISOLATED SHOWERS ARE OVERRUNNING THE COLD FRONT EXTENDING FROM 
THE WINDWARD PASSAGE TO NE NICARAGUA. MODERATE/STRONG EASTERLY 
TRADE WINDS DOMINATES THE ENTIRE CARIBBEAN WITH AN UPPER LEVEL 
RIDGE DOMINATING THE AREA ANCHORED OFF THE COAST OF PANAMA NEAR 
12N79W AND THE RIDGE AXIS EXTENDING ENE ACROSS PUERTO RICO/ 
VIRGIN ISLANDS INTO THE W/CENTRAL ATLC. STRONG SUBSIDENCE AND 
VERY DRY UPPER AIR ALSO DOMINATES THE CARIBBEAN ALTHOUGH SOME 
ISOLATED LOW-LEVEL SHOWERS ARE POSSIBLE OVER THE LESSER 
ANTILLES. 

ATLANTIC OCEAN...
THE SURFACE RIDGE ANCHORED IN THE CENTRAL GULF OF MEXICO EXTENDS 
INTO THE W ATLC W OF THE SLOW MOVING COLD FRONT THAT ENTERS THE 
AREA NEAR 32N54W AND CONTINUES SW ALONG 26N64W ACROSS CUBA INTO 
THE CARIBBEAN NEAR 20N76W. DENSE LOW/MID LEVEL CLOUDS AND 
ISOLATED SHOWERS ARE WITHIN 200 NM W OF THE FRONT. THE 
ASSOCIATED UPPER LEVEL TROUGH DIPS S OVER THE NW ATLC AND OVER 
THE E US WITH MOST OF THE UPPER LEVEL ENERGY N OF THE REGION. A 
SUBTROPICAL JET WITH WINDS OF 90 TO 130 KT THAT COVERS THE GULF 
EXTENDS INTO THE W ATLC ACROSS N FLORIDA THEN NE TO BEYOND 
32N70W. UPPER RIDGE ANCHORED IN THE CARIBBEAN EXTENDS AN AXIS NE 
ACROSS PUERTO RICO/VIRGIN ISLANDS TO BEYOND 32N48W. AN UPPER 
TROUGH IS OVER THE E ATLC EXTENDING FROM AN UPPER LOW OFF THE 
WESTERN SAHARA COAST NEAR 23N20W SW TO 15N36W IN THE TROPICAL 
ATLC. THE E ATLC IS DOMINATED BY A SURFACE RIDGE THAT EXTENDS 
FROM A 1031 MB HIGH JUST SE OF THE AZORES TO THE NE CARIBBEAN 
SUPPLYING MOSTLY FAIR WEATHER AND MODERATE TRADES ACROSS A GOOD 
PORTION OF THE REGION. 

$$
WALLACE