000 AXNT20 KNHC 281155 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI DEC 28 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC ...THE ITCZ... FROM THE SIERRA LEONE/LIBERIA BORDER TO 6N20W 4N30W 2N40W... CROSSING THE EQUATOR ALONG 50W TO NORTHEASTERN COASTAL BRAZIL NEAR 1S51W. SCATTERED MODERATE TO STRONG SHOWERS AND THUNDERSTORMS ARE FROM 2N TO 4N BETWEEN 27W AND 33W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS FROM 2N TO 6N BETWEEN 44W AND THE COASTS OF BRAZIL AND FRENCH GUIANA. ISOLATED MODERATE SHOWERS ELSEWHERE SOUTH OF 10N. ...DISCUSSION... THE GULF OF MEXICO... A BAND OF MIDDLE TO UPPER LEVEL MOISTURE IS WITHIN 180 NM TO 240 NM ON EITHER SIDE OF 19N110W IN THE EASTERN PACIFIC OCEAN...CROSSING MEXICO NEAR 24N100W...INTO THE NORTHERN GULF OF MEXICO NEAR 29N90W...CROSSING FLORIDA AND INTO THE ATLANTIC OCEAN BEYOND 32N84W IN GEORGIA. MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE IS ON EITHER SIDE OF THE BAND OF MOISTURE. THE DRY AIR/SUBSIDENCE IS PUSHING NORTHWARD FROM THE SOUTHERN SECTIONS OF THE GULF OF MEXICO. THE UPPER LEVEL WIND FLOW IS FROM THE SOUTHWEST IN THE BAND OF MOISTURE. ANOTHER MIDDLE TO UPPER LEVEL TROUGH IS MOVING THROUGH THE NORTHERN HALF OF TEXAS. A WARM FRONT HUGS THE U.S.A. GULF COAST STATES FROM THE FLORIDA PANHANDLE TO TEXAS. AREAS OF RAIN ARE LIKELY ALONG THE FRONT. THE CARIBBEAN SEA... MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW EXTENDS FROM THE WEST CENTRAL CARIBBEAN SEA NORTHEASTWARD INTO THE ATLANTIC OCEAN BEYOND 32N61W. THE FAR EASTERN CARIBBEAN SEA EXPERIENCES THE TAIL END OF THE DEEP LAYER TROUGH FROM THE ATLANTIC OCEAN 26N37W CYCLONIC CIRCULATION CENTER. BROAD MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA. DRY AIR/SUBSIDENCE IS EVERYWHERE EXCEPT FOR THE HIGH LEVEL MOISTURE IN THE WEST CENTRAL SECTIONS AND SOUTHWESTERN CORNER OF THE AREA. SHOWERS/THUNDERSTORMS ARE IN INDIVIDUAL CELLS IN A LINE FROM THE EASTERN COAST OF PANAMA TO SOUTHEASTERN NICARAGUA. BROAD SURFACE LOW PRESSURE IN THE SOUTHWESTERN CORNER OF THE AREA HAS RELAXED A BIT AS COMPARED TO THE 1006 MB LOW PRESSURE CENTER NEAR THE GULF OF URABA OF COLOMBIA AT 28/0000 UTC. SHOWERS ARE POSSIBLE IN BROKEN LOW CLOUDS IN SURFACE EASTERLY WIND FLOW...NORTH OF 13N60W 14N70W 18N80W...AND SOUTH OF 20N WEST OF 80W. THE ATLANTIC OCEAN... MIDDLE TO UPPER LEVEL ANTICYCLONIC WIND FLOW EXTENDS FROM THE WEST CENTRAL CARIBBEAN SEA NORTHEASTWARD BEYOND 32N60W. A SURFACE TROUGH REMAINS FROM 31N66W TO 27N77W IN THE NORTHERN BAHAMAS. THE MIDDLE TO UPPER LEVEL SUPPORT FOR THIS FEATURE HAS BEEN WEAKENED BY THE RIDGE. A DEEP LAYER CYCLONIC CIRCULATION CENTER REMAINS IN THE CENTRAL ATLANTIC OCEAN NEAR 26N38W ON WATER VAPOR IMAGERY...AND A 1009 MB LOW PRESSURE CENTER IS NEAR 26N37W ON THE 28/0600 UTC SURFACE MAP ANALYSIS. THE DEEP LAYER TROUGH RUNS FROM THE 26N37W CYCLONIC CENTER TO 20N45W 15N51W TO 14N60W. ONE SURFACE TROUGH EXTENDS FROM THE 1009 MB LOW CENTER TO 24N35W 17N40W 13N50W 12N55W. A SECOND SURFACE TROUGH EXTENDS FROM THE LOW CENTER TO 20N40W 18N44W 17N51W. SHOWERS ARE POSSIBLE IN NARROW LINES ALONG EACH TROUGH. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM 24N TO 30N BETWEEN 30W AND 40W. UPPER LEVEL SOUTHWESTERLY WIND FLOW IS SOUTH OF THE LINE FROM THE VENEZUELA/GUYANA COASTS NEAR 8N60W TO 10N50W 16N40W 22N30W BEYOND 23N17W. $$ MT