000 AXNT20 KNHC 181159 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI JAN 18 2008 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 5N3W 4N10W 3N20W...CROSSING THE EQUATOR AT 33W...STAYING JUST SOUTH OF THE EQUATOR TO 44W...AND CONTINUING INTO NORTHEASTERN BRAZIL NEAR 1S50W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE SOUTH OF 7N EAST OF 40W... AND SOUTH OF 10N ELSEWHERE WEST OF 40W. ...DISCUSSION... THE GULF OF MEXICO... BROAD MIDDLE TO UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE AREA. THE FRONTAL BOUNDARY IN THE GULF OF MEXICO LACKS STRONG SUPPORT IN THE MIDDLE TO UPPER LEVELS OF THE ATMOSPHERE. A COLD FRONT RUNS FROM A 1015 MB LOW PRESSURE CENTER NEAR 30N80W IN THE ATLANTIC OCEAN TO CENTRAL FLORIDA...TO THE COASTAL WATERS OF THE NORTHERN YUCATAN PENINSULA. THE FRONT BECOMES WARM AND CONTINUES TO A 1012 MB LOW PRESSURE CENTER IN THE SOUTHWESTERN CORNER OF THE AREA. A STATIONARY FRONT CONTINUES INTO MEXICO TO 22N100W AND FINALLY TO 26N106W. SHOWERS/THUNDERSTORMS ARE FROM 21N TO 22N BETWEEN 94W AND 95W...AND WITHIN A 15 NM TO 30 NM RADIUS OF 22N91W. THE CARIBBEAN SEA... BROAD UPPER LEVEL ANTICYCLONIC FLOW COVERS THE ATLANTIC OCEAN SOUTH OF 32N WEST OF 55W...INCLUDING IN THE CARIBBEAN SEA. A MIDDLE LEVEL ANTICYCLONIC CIRCULATION CENTER IS SUPPOSED TO BE ABOUT 90 NM NORTH OF EASTERN HISPANIOLA ACCORDING TO THE GFS MODEL. SUCH A CENTER IS NOT EASY TO SEE WITH THE NAKED EYE ON SATELLITE IMAGERY. MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE COVERS THE ENTIRE AREA. SURFACE EASTERLY WIND FLOW IS LOOSELY RELATED TO LARGE SCALE ANTICYCLONIC FLOW. NO ANTICYCLONIC CIRCULATION CENTER IS ANYWHERE NEAR THE CARIBBEAN SEA. ONE CENTER IS ABOUT 150 NM EAST-NORTHEAST OF BERMUDA IN THE ATLANTIC OCEAN. LARGE-SCALE ANTICYCLONIC FLOW FROM THIS ATLANTIC OCEAN HIGH PRESSURE CENTER REACHES THE CARIBBEAN SEA. THE ISOBARS ON THE SURFACE MAP DO NOT APPEAR TO SHOW A STRONG PRESSURE GRADIENT. THAT DOES NOT MEAN THAT A SLIGHT CHANGE IN THE PRESSURE FIELD IS NOT ABLE TO GENERATE COMPARATIVELY STRONGER WIND SPEEDS ACROSS THE OPEN WATERS OF THE CARIBBEAN SEA. AN EXAMPLE OF FAST WINDS FROM WHAT DOES NOT APPEAR TO BE SUCH A STRONG GRADIENT ACCORDING TO THE ISOBARIC ANALYSIS IS FROM 10N TO 18N BETWEEN 70W AND 80W NORTHEAST-TO-EAST WINDS FROM 20 KT TO 30 KT AND SEAS FROM 8 TO 13 FT. THE 24 HOUR AND 48 HOUR FORECASTS DO NOT CHANGE MUCH FOR THIS AREA. THE ATLANTIC OCEAN... A WESTERN ATLANTIC COLD FRONT RUNS FROM A 1015 MB LOW PRESSURE CENTER NEAR 30N80W IN THE ATLANTIC OCEAN TO CENTRAL FLORIDA... TO THE COASTAL WATERS OF THE NORTHERN YUCATAN PENINSULA. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE ALONG THIS FRONT FROM 29N TO 33N BETWEEN 70W AND 77W. AN ATLANTIC OCEAN COLD FRONT PASSES THROUGH THE EAST CENTRAL SECTIONS NEAR 32N38W TO 24N50W TO 22N66W. A MIDDLE TO UPPER LEVEL TROUGH PASSING THROUGH 33N47W 27N50W 24N51W SUPPORTS THIS COLD FRONT. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE WITHIN 90 NM ON EITHER SIDE OF 22N57W 26N44W BEYOND 32N35W. A 1027 MB HIGH PRESSURE CENTER IS ABOUT 150 NM EAST-NORTHEAST OF BERMUDA. THIS HIGH PRESSURE CENTER AND ITS ASSOCIATED FLUCTUATIONS IN THE PRESSURE GRADIENT ARE PRODUCING 20 KT TO 30 KT WIND SPEEDS IN THE SOUTH CENTRAL CARIBBEAN SEA...AND IN PARTS OF THE ATLANTIC OCEAN. PLEASE REFER TO THE MIAHSFAT2 HIGH SEAS FORECAST FOR SPECIFIC FORECAST INFORMATION. AN ATLANTIC OCEAN MIDDLE TO UPPER LEVEL TROUGH PASSES THROUGH 32N25W TO 21N31W TO 15N37W TO NORTHERN GUYANA. A SURFACE RIDGE IS EAST OF THE 32N39W 23N66W COLD FRONT ALONG 20N50W 26N31W BEYOND 32N20W. $$ MT