000 AXNT20 KNHC 270616 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU DEC 27 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC ...THE ITCZ... FROM NORTHERN COASTAL SIERRA LEONE TO 6N20W 4N30W...CROSSING THE EQUATOR ALONG 40W TO NORTHEASTERN COASTAL BRAZIL NEAR 2S44W. ISOLATED MODERATE SHOWERS AND POSSIBLE LOCAL THUNDERSTORMS ARE SOUTH OF 7N EAST OF 50W. OVERCAST HIGH CLOUDS ARE WITHIN 180 NM TO 240 NM ON EITHER SIDE OF 23N24W 15N32W 9N39W...AND FROM 15N TO 20N BETWEEN AFRICA AND 26W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE TO UPPER LEVEL TROUGH IS DIGGING SOUTHWARD THROUGH CALIFORNIA INTO THE NORTHERN HALF OF THE BAJA PENINSULA AND NORTHERN MEXICO. DRY MIDDLE TO UPPER LEVEL WESTERLY-TO- SOUTHWESTERLY WIND FLOW CROSSES MEXICO NORTH OF 22N. A BAND OF MOISTURE FROM THE EASTERN PACIFIC OCEAN IS WITHIN 120 NM TO 180 NM ON EITHER SIDE OF THE LINE THROUGH 17N109W TO 20N100W IN MEXICO TO THE CENTRAL GULF OF MEXICO NEAR 26N90W BEYOND 30N/83W ALONG THE FLORIDA/GEORGIA BORDER. MORE DRY AIR IS SOUTHEAST OF THE MOISTURE BAND. A MIDDLE TO UPPER LEVEL TROUGH PASSES THROUGH LOUISIANA TO DEEP SOUTH TEXAS. THIS TROUGH SUPPORTS THE COLD FRONT THAT PASSES THROUGH THE NORTH CENTRAL U.S.A. GULF COAST STATES INTO THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO. A SURFACE RIDGE COVERS SOUTH CAROLINA/GEORGIA/ FLORIDA. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE SHOWERS ARE WITHIN 60 NM ON EITHER SIDE OF THE FRONT. THE FORECAST IS FOR THIS FRONT TO DISSIPATE DURING THE NEXT 24 HOURS. A SECOND FRONT WILL FOLLOW THE FIRST ONE...BUT NOT FOR ANOTHER FEW DAYS...TO BE IN THE WESTERN GULF OF MEXICO BY 29/0000 UTC. THE CARIBBEAN SEA... ONE AREA OF UPPER LEVEL ANTICYCLONIC FLOW/RIDGE IS IN THE WESTERN CARIBBEAN SEA. THIS RIDGE HAS AMPLIFIED FROM ITS STATE OF 24 HOURS AGO. THE RIDGE NOW POKES AS FAR NORTH AS CUBA AND THE BAHAMAS SOUTH OF 24N. MIDDLE TO UPPER LEVEL DRY AIR/ SUBSIDENCE EVERYWHERE. HIGH LEVEL CLOUDS FROM EASTERN PACIFIC OCEAN ITCZ PRECIPITATION HAS CROSSED THE AREA OF NORTHWESTERN COLOMBIA/PANAMA/COSTA RICA INTO THE SOUTHWESTERN CORNER OF THE AREA. THE MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW FROM THE WESTERN CARIBBEAN SEA RIDGE COVERS THE AREA AS FAR TO THE EAST AS 66W. THE ATLANTIC OCEAN-TO-CARIBBEAN SEA MIDDLE TO UPPER LEVEL TROUGH REACHES 15N62W IN THE EASTERN CARIBBEAN SEA. THE TROUGH IS SURROUNDED BY ALL THE DRY AIR/SUBSIDENCE. A LITTLE BIT OF BROAD SURFACE LOW PRESSURE MOVES FROM NORTHERN COLOMBIA INTO THE SOUTHWESTERN CORNER OF THE AREA. THE 1008 MB ISOBAR MOVES FROM COLOMBIA INTO THE SOUTHWESTERN CORNER OF THE AREA IN ORDER TO COVER THE FEW COMPARATIVELY LOWER 1005 MB OBSERVATIONS IN THAT AREA. POSSIBLE SHOWERS IN BROKEN LOW TO MIDDLE LEVEL CLOUDS NORTH OF 18N70W 16N63W 14N60W...FROM 15N TO 20N BETWEEN 72W AND 82W...AND FROM 16N TO 20N BETWEEN 83W AND 85W. THE ATLANTIC OCEAN... A DEEP LAYER TROUGH IS IN THE WESTERN ATLANTIC OCEAN STRETCHING FROM THE WATERS EAST OF VIRGINIA THROUGH 33N73W TO 30N75W. THIS TROUGH SUPPORTS THE COLD FRONT THAT PASSES THROUGH 32N71W TO 30N73W TO THE NORTHERN BAHAMAS NEAR 25N78W. THIS FRONT IS SURROUNDED BY MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE. ISOLATED MODERATE SHOWERS ARE EAST OF THE FRONT IN AN AREA OF UPPER LEVEL DIFFLUENT WIND FLOW NORTH OF 28N BETWEEN 60W AND 70W. MIDDLE TO UPPER LEVEL ANTICYCLONIC WIND FLOW...FROM THE CARIBBEAN SEA RIDGE...COVERS THE ATLANTIC OCEAN WEST OF 54W. A DEEP LAYER CYCLONIC CIRCULATION CENTER REMAINS IN THE CENTRAL ATLANTIC OCEAN NEAR 21N54W ON WATER VAPOR IMAGERY...AND A 1012 MB LOW PRESSURE CENTER IS NEAR 26N41W ON THE 27/0000 UTC SURFACE MAP ANALYSIS. THE DEEP LAYER TROUGH RUNS FROM THE 21N54W CYCLONIC CENTER TO 19N41W 16N49W TO 15N62W IN THE EASTERN CARIBBEAN SEA. AN OCCLUDED FRONT EXTENDS FROM THE 26N41W SURFACE LOW PRESSURE CENTER NORTHEASTWARD TO 31N41W. A STATIONARY FRONT CONTINUES FROM THE 26N41W LOW PRESSURE CENTER TO 25N38W AND 20N41W. WIDELY SCATTERED TO SCATTERED MODERATE SHOWERS AND ISOLATED STRONG THUNDERSTORMS ARE FROM 22N BEYOND 32N BETWEEN 33W AND 40W. $$ MT