000
AXNT20 KNHC 040542
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST THU DEC 04 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND 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 0515 UTC.

...THE ITCZ...
FROM 8N11W IN SIERRA LEONE TO 4N25W 7N44W TO 5N55W IN SURINAME.
STRONG SHOWERS AND THUNDERSTORMS ARE FROM 4N TO 5N BETWEEN
9W AND 11W...AND FROM 3N TO 5N BETWEEN 28W AND 30W. ISOLATED 
MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE ELSEWHERE
SOUTH OF 10N BETWEEN AFRICA AND SOUTH AMERICA.

...DISCUSSION...

THE GULF OF MEXICO...
THE NEXT DEEP LAYER TROUGH THAT IS DRIVING A COLD FRONT IS SWEEPING 
ACROSS TEXAS FROM WEST TO EAST. DEEP LAYER MOISTURE THAT IS TO THE 
SOUTH AND SOUTHEAST OF THIS TROUGH MOVES FROM CENTRAL MEXICO THROUGH 
THE NORTHWESTERN GULF/TEXAS COASTAL WATERS...AND NORTHEASTWARD 
BEYOND LOUISIANA. THE COLD FRONT STILL IS IN TEXAS RIGHT NOW...FROM 
EAST TEXAS TO SOUTH CENTRAL TEXAS TO THE TEXAS BIG BEND AND BEYOND.
MIDDLE TO UPPER LEVEL DRY AIR IN SUBSIDENCE IS SOUTHEAST OF 31N85W
27N90W 21N97W. THE DEEP LAYER TROUGH THAT WAS POWERING THE COLD
FRONTS OF THE LAST FEW DAYS HAS LOST ITS EARLIER DEFINITION...AND
IT EXTENDS FROM THE ATLANTIC OCEAN THROUGH 32N68W ACROSS THE
NORTHERN BAHAMAS TO 24N80W. IT IS SURROUNDED BY MIDDLE TO UPPER
LEVEL DRY AIR IN SUBSIDENCE. A SURFACE RIDGE PASSES THROUGH 32N77W
IN THE ATLANTIC OCEAN...ACROSS FLORIDA...INTO THE GULF OF MEXICO
NEAR 27N84W...TO THE NORTHEASTERN YUCATAN PENINSULA...TO EL SALVADOR.

THE CARIBBEAN SEA...
THE STATIONARY FRONT CUTS ACROSS SOUTHEASTERN CUBA TO JUST NORTHWEST 
OF JAMAICA TO 17N80W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG 
THUNDERSTORMS ARE FROM THE COAST OF PANAMA TO 14N BETWEEN 79W AND 
THE COAST OF NICARAGUA. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS 
THE THE ENTIRE AREA...THANKS TO THE UPPER LEVEL RIDGE ALONG 25N57W 
20N62W 16N64W INTO VENEZUELA NEAR 7N70W. THE TROUGH/TROPICAL WAVE 
NOW IS ALONG 74W/75W SOUTH OF 16N...MOVING WEST 10 KT OR LESS.
NO DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THE WAVE.

THE ATLANTIC OCEAN...
THE PERSISTENT DEEP LAYER TROUGH PASSES THROUGH 32N40W IN THE 
CENTRAL ATLANTIC OCEAN TO 20N45W TO 10N54W. AN UPPER LEVEL RIDGE
PASSES THROUGH 32N53W TO 25N57W...INTO THE CARIBBEAN SEA NEAR
16N64W INTO VENEZUELA NEAR 7N70W. THE DEEP LAYER TROUGH THAT NOW
IS POWERING THE COLD FRONT/STATIONARY FRONT PASSES THROUGH 32N68W 
ACROSS THE NORTHERN BAHAMAS TO 24N80W. MIDDLE TO UPPER LEVEL DRY
AIR IS WITHIN 400 NM ON EITHER SIDE OF TROUGH. THE COLD FRONT PASSES
THROUGH 32N62W TO 30N65W. THE FRONT CONTINUES AS STATIONARY FROM 
30N65W TO 25N70W TO CUBA NEAR 20N77W...INTO THE CARIBBEAN SEA NEAR 
17N80W. A SURFACE RIDGE IS ALONG 10N31W 18N33W 23N29W 27N27W BEYOND 
32N24W. AN AMPLIFIED UPPER LEVEL RIDGE IS ALONG THE LINE FROM
6N25W TO 18N23W TO 26N27W BEYOND 33N29W.

$$
MT