000 AXNT20 KNHC 301804 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI MAR 30 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... 6N8W 3N20W...FROM THE EQUATOR TO 1N ALONG 30W AND 44W...AND TO 1S51W. ISOLATED TO WIDELY SCATTERED MODERATE SHOWERS/POSSIBLE THUNDERSTORMS FROM 2N TO 4N BETWEEN 20W AND 40W...AND FROM 1N TO 2N BETWEEN 32W AND 34W. ISOLATED MODERATE SHOWERS FROM 3N TO 7N BETWEEN 10W AND 20W. ISOLATED TO WIDELY SCATTERED MODERATE SHOWERS/LOCALLY STRONG THUNDERSTORMS FROM THE EQUATOR TO 7N BETWEEN 49W AND 55W...FROM EXTREME NORTHEASTERN BRAZIL TO SURINAME AND FRENCH GUIANA. ISOLATED MODERATE SHOWERS ELSEWHERE FROM THE EQUATOR TO 6N BETWEEN 46W AND 50W. ...DISCUSSION... THE GULF OF MEXICO... DEEP LAYER CYCLONIC FLOW COVERS THE U.S.A. FROM MEXICO NORTHWARD BEYOND 32N BETWEEN 97W IN EAST CENTRAL TEXAS AND KANSAS...AND THE UTAH/NEVADA BORDER. BROAD UPPER LEVEL ANTICYCLONIC FLOW MOVES FROM CENTRAL TEXAS ACROSS THE GULF OF MEXICO. AN UPPER LEVEL RIDGE EXTENDS FROM THE EAST CENTRAL GULF OF MEXICO NORTHWARD BEYOND ALABAMA. HIGH CLOUDS ARE MOVING ACROSS THE GULF WATERS WHERE MIDDLE TO UPPER LEVEL DRY AIR ALREADY HAS BEEN IN PLACE. A SURFACE RIDGE RUNS THROUGH THE FLORIDA PANHANDLE NEAR 30N85W TO THE CENTRAL GULF...TO THE SOUTHWESTERN CORNER OF THE AREA. A DISSIPATING COLD FRONT IS IN THE ATLANTIC OCEAN...APPROACHING THE NORTHEASTERN FLORIDA COAST AND THE BAHAMAS. THE CARIBBEAN SEA... UPPER LEVEL WESTERLY TO SOUTHWESTERLY WIND FLOW COVERS THE AREA. THE WESTERLY COMPONENT IS DUE TO AN EAST-WEST UPPER LEVEL RIDGE ALONG 7N. UPPER LEVEL CLOUDS ARE PASSING ON TOP OF MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE THAT ALREADY IS IN PLACE. SURFACE TO LOW LEVEL WINDS ARE GENERALLY FROM THE NORTHEAST. THE ATLANTIC OCEAN... CYCLONIC FLOW FROM A DEEP LAYER TROUGH COVERS THE ATLANTIC OCEAN NORTH OF 20N WEST OF 50W. A TROUGH ON CURRENT WATER VAPOR SATELLITE IMAGERY STARTS FROM A CYCLONIC CIRCULATION CENTER NEAR 32N62W TO 26N66W TO 20N68W. MIDDLE TO UPPER LEVEL DRY AIR SURROUNDS THIS TROUGH AND THE AREA OF CYCLONIC FLOW AROUND THE TROUGH. ONE SURFACE COLD FRONT PASSES THROUGH 32N50W TO 25N60W TO 24N70W. A DISSIPATING COLD FRONT GOES FROM 24N70W TO 26N77W NEAR THE BAHAMAS...TO 30N81W NEAR NORTHEASTERN FLORIDA. A SECOND AND DISSIPATING COLD FRONT IS WITHIN 300 TO 400 NM TO THE NORTH OF THE FIRST COLD FRONT. A SURFACE TROUGH GOES FROM 31N47W TO 27N50W...TO A 1010 MB LOW PRESSURE CENTER NEAR 25N50W TO 20N53W TO 17N61W. THE 1010 MB LOW CENTER IS AT THE SOUTHWESTERN EDGE OF THE BAROCLINIC-LEAF CLOUD PATTERN ON CURRENT WATER VAPOR SATELLITE IMAGERY. ISOLATED MODERATE SHOWERS ARE WITHIN 30 TO 60 NM ON EITHER SIDE OF 25N58W 27N55W 30N52W BEYOND 31N51W. ISOLATED MODERATE SHOWERS TO POSSIBLE THUNDERSTORMS ARE NORTH OF 20N BETWEEN 40W AND 50W. A SURFACE RIDGE PASSES THROUGH 31N29W TO 25N34W TO 19N38W. AN UPPER RIDGE IS ALONG 19N42W 26N40W BEYOND 31N40W. BROAD CYCLONIC FLOW FROM A MIDDLE TO UPPER LEVEL TROUGH COVERS THE ATLANTIC WATERS EAST OF THE RIDGE. THE TROUGH PASSES THROUGH 31N21W TO 24N24W TO 17N30W. $$ MT