000
AXNT20 KNHC 052307
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST FRI JAN 05 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2245 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 2N AT THE PRIME MERIDIAN TO 14W THEN 
ALONG 5N28W 3N40W CROSSING THE EQUATOR AT 46W. ISOLATED 
SHOWERS/THUNDERSTORMS FROM THE EQUATOR TO 8N BETWEEN 22W-44W. 

...DISCUSSION...
GULF OF MEXICO...
DEEP LAYERED TROUGH COVERS THE SE US AND THE GULF N OF 23N W OF 
80W WITH THE ASSOCIATED COLD FRONT ENTERING THE GULF OVER 
CENTRAL ALABAMA ALONG 30N87W TO 26N92W. LINE OF STRONG 
THUNDERSTORMS EXTENDS FROM 27N86W ACROSS FLORIDA NEAR 30N83W TO 
OVER E GEORGIA WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS 
COVERING THE REMAINDER OF THE NE GULF N OF 27N E OF 86W ACROSS 
NE FLORIDA AND PORTIONS OF GEORGIA/SOUTH CAROLINA. REMAINDER OF 
THE GULF HAS DRY AIR AT ALL LEVELS AND STRONG SUBSIDENCE LENDING 
TO CLEAR SKIES AND NO SHOWER ACTIVITY. ANOTHER COLD FRONT IS 
EXPECTED TO APPROACH THE GULF ALONG THE TEXAS COAST LATE 
SATURDAY. 

CARIBBEAN SEA...
UPPER RIDGE COVERING THE W CARIBBEAN W OF 70W EXTENDS FROM 
PANAMA/COSTA RICA BORDER ACROSS CUBA NEAR 22N79W INTO THE W 
ATLC. DEEP LAYERED TROUGH IN THE W/CENTRAL ATLC EXTENDS S OVER 
THE REMAINDER OF THE CARIBBEAN ACROSS THE LESSER ANTILLES INTO 
THE W TROPICAL ATLC. DRY AIR AND VERY STRONG SUBSIDENCE 
DOMINATES THE ENTIRE CARIBBEAN LEAVING ONLY WIDELY ISOLATED LOW 
LEVEL SHOWERS DOTTING THE REGION. STRONG EASTERLY TRADE WINDS 
CONTINUE TO DOMINATE THE CARIBBEAN...ALTHOUGH BELOW GALE FORCE. 

ATLANTIC OCEAN...
UPPER RIDGE EXTENDS INTO THE W ATLC FROM THE CARIBBEAN ACROSS 
CUBA NEAR 22N79W TO BEYOND 32N74W COVERING THE W ATLC W OF 70W. 
DEEP LAYERED TROUGH COVERS THE REMAINDER OF THE W ATLC AND THE 
CENTRAL ATLC INCLUDING THE E CARIBBEAN AND PORTION OF THE W 
TROPICAL ATLC WITH AN EMBEDDED UPPER LOW NEAR 26N55W. THE 
ASSOCIATED FRONTAL BOUNDARY IS NEAR STATIONARY EXTENDING THROUGH 
32N39W TO 30N46W WHERE IT BEGINS TO DISSIPATE ALONG 28N57W TO 
29N65W. A SURFACE TROUGH...REFLECTION OF THE UPPER LOW...EXTENDS 
FROM 25N50W TO 19N56W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS 
ARE WITHIN 90/120 NM OF THE SURFACE TROUGH. ISOLATED SHOWERS ARE 
WITHIN 90/120 NM OF THE FRONTAL BOUNDARY E OF 55W. A SECOND 
UPPER TROUGH COVERS THE E ATLC FROM 26W-38W WITH YET ANOTHER 
UPPER LOW NEAR 25N33W AND A WEAK UPPER RIDGE BETWEEN THESE UPPER 
TROUGHS. A BROAD UPPER RIDGE IS OVER THE FAR E ATLC WITH THE 
AXIS ALONG 18W. ALTHOUGH TROPICAL MOISTURE IS BEING ADVECTED N 
OVER THE FAR E ATLC...DUE TO THE DRY AIR ALREADY IN PLACE...FEW 
SHOWERS ARE FORMING. A JET STREAM WITH WINDS NEAR 90 KT IS 
ACROSS THE TROPICAL ATLC EXTENDING FROM 13N54W ALONG 17N37W TO 
13N21W. 

$$
WALLACE