000 AXNT20 KNHC 192336 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU MAR 19 2009 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 4N8W 1N20W CROSSING THE EQUATOR NEAR 27W EXTENDING TO NE BRAZIL NEAR 2S43W. CLUSTERS OF ISOLATED MODERATE CONVECTION IS WITHIN 90 NM OF THE ITCZ BETWEEN 9W AND 27W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A QUASI-STATIONARY SURFACE TROUGH IS CENTERED OVER THE CENTRAL GULF OF MEXICO FROM 22N89W TO 27N90W. A BAND OF BROKEN LOW CLOUDS WITH ISOLATED SHOWERS AND POSSIBLE THUNDERSTORMS ARE OVER THE N CENTRAL GULF WITHIN 45-60 NM OF A LINE FROM 25N86W TO 26N90W TO 26N93W. MOSTLY FAIR SKIES REMAIN OVER THE W GULF AS A RIDGE AXIS EXTENDS ALONG THE TEXAS COAST AND SOUTHWARD TO THE BAY OF CAMPECHE WITH A 1020 MB HIGH ABOUT 120 NM ENE OF VERACRUZ MEXICO. SURFACE WINDS ARE FROM THE NE TO E AT 10 TO 15 KT OVER THE GULF...DECREASING TO 5-10 KT CLOSER TO THE COAST. IN THE UPPER LEVELS...A WEAK UPPER LEVEL SHORTWAVE TROUGH EXTENDS FROM THE RIO GRANDE VALLEY SOUTHWARD TO NEAR MEXICO CITY WAS MOVING E AT 10-15 KT. MOSTLY ZONAL FLOW WAS NOTED OVER THE REMAINDER OF THE E-CENTRAL GULF. THE WEAK SHORTWAVE OVER THE EASTERN GULF HAS MOVED INTO THE W ATLC NEAR THE BAHAMAS. CARIBBEAN SEA... FRESH TRADEWINDS ARE OVER THE EASTERN AND SOUTHWESTERN CARIBBEAN SEA WITH THE LAST SCATTEROMETER PASS INDICATING WINDS UP TO 25 KT IN ALONG THE COAST OF NRN COLOMBIA. A SHIP WITH CALL SIGN ZCDF4 WAS ALONG THE COAST OF COLOMBIA AND REPORTED 25 TO 30 KT WINDS AND 11 FT SEAS OVER THE PAST FEW HOURS. LIGHT WINDS PREVAIL OVER THE NORTHERN CARIBBEAN WITH SPEEDS IN THE 5 TO 10 KT RANGE...AS SUBSIDENCE AND FAIR WEATHER PREDOMINATE. HOWEVER...A FEW PATCHES OF BROKEN LOW CLOUDS WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE NEAR HISPANIOLA ...JAMAICA...AND CUBA. THESE SHOWERS HAVE WEAKENED AS DAYTIME HEATING WANES AND THE ATMOSPHERE HAS BECOME MORE STABLE. THERE WAS ALSO A MARKED DECREASE IN LIGHTNING DATA COVERAGE OVER CUBA AS WELL. IN THE UPPER LEVELS...WEAK ZONAL FLOW WILL PERSIST OVER THE AREA OVER THE NEXT 24 HOURS...AS A WEAK SHORT WAVE PASSES TO THE N OF THE REGION OVER THE SW ATLANTIC. ATLANTIC OCEAN... A STRONG COLD FRONT EXTENDS FROM 32N43W SW ALONG 26N50W TO 23N62W...THEN BECOMES STATIONARY ALONG 24N WHILE EXTENDING WESTWARD THROUGH THE CENTRAL BAHAMAS. A 1250 UTC ASCAT PASS INDICATED GALE FORCE WINDS BRUSHING THE NORTHERN PERIPHERY OF THE DISCUSSION AREA WITH NEAR STORM FORCE WINDS FURTHER N. A SHIP WITH CALL SIGN PCBV LOCATED NEAR 30N48W AT 18 UTC REPORTED GALE FORCE WEST WINDS AND 26 FT SEAS. THE GALES ARE EXPECTED TO MOVE N OF THE DISCUSSION AREA OVERNIGHT AS THE PARENT SYSTEM MOVES NE. OVERCAST LOW AND MID CLOUDS WITH SCATTERED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE FRONT AND ARE EXPECTED TO PERSIST INTO FRI. AN AREA OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CURRENTLY N OF THE FRONT TO 29N BETWEEN 70W AND 76W IS SPREADING NE AHEAD OF AN UPPER LEVEL SHORTWAVE TROUGH. A 1024 MB HIGH IS JUST N OF THE DISCUSSION AREA CENTERED NEAR 35N62W...WITH A RIDGE EXTENDING SE TO 26N58W...BEHIND THE COLD FRONT. ANOTHER COLD FRONT FURTHER EAST EXTENDS FROM 32N15W SW TO 26N20W TO 24N33W. SCATTERED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE FRONT... AND ARE EXPECTED TO DIMINISH OVER THE NEXT 24 HOURS AS THE FRONT WEAKENS. IN THE UPPER LEVELS...A RATHER SHARP UPPER LEVEL SHORTWAVE TROUGH IS SWEEPING ACROSS THE CENTRAL BAHAMAS AND APPEARS TO BE AMPLIFYING WITH TIME AND PRODUCING A LARGE AREA OF MULTILAYERED CLOUDS AS NOTED ABOVE. ELSEWHERE N OF 20N...A PREDOMINANTLY ZONAL FLOW EXIST E OF 70W TO 30W WITH A DOWNSTREAM TROUGH APPROACHING THE WEST COAST OF AFRICA N OF 12N. A BROAD UPPER LEVEL RIDGE WAS NOTED S OF 20N W OF 35W WITH THE PARENT HIGH CENTERED OVER THE TROPICAL E ATLANTIC NEAR 2N41W. A RATHER SHARP UPPER LEVEL SHORTWAVE TROUGH NEAR 31N46W WILL LIFT NE OVER THE NEXT 24 HOURS. $$ COBB