000 AXNT20 KNHC 251751 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT APR 25 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N8W 3N15W CROSSING THE EQUATOR NEAR 23W EXTENDING JUST SOUTH OF THE EQUATOR TO 1S36W AND INTO NE BRAZIL NEAR 3S42W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM THE EQUATOR TO 5N E OF 3W. ELSEWHERE...SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 6N BETWEEN 10W-16W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYER DRY AIR AND SW TO W FLOW ALOFT ARE PRESENT ACROSS MUCH OF THE GULF REGION. SUBSIDENCE ASSOCIATED WITH A 1032 MB SURFACE HIGH OVER THE W ATLC NEAR 34N69W EXTENDS A SURFACE RIDGE ACROSS THE NRN GULF ALONG 30N AND IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. THE SURFACE FLOW AROUND THIS SURFACE RIDGE IS RESULTING IN E TO SE WINDS OF 20 TO 25 KT ACROSS MOST OF THE GULF WITH THE EXCEPTION OF 10 TO 15 KT WINDS IN THE FAR NE GULF NEAR THE FLORIDA BIG BEND REGION. THIS OVERALL WEATHER PATTERN IS FORECAST TO REMAIN IN PLACE THROUGH THE WEEKEND AS THE SURFACE HIGH IN THE W ATLC REMAINS QUASI-STATIONARY AND PROVIDES FRESH TO STRONG E TO SE SURFACE WINDS ACROSS THE REGION. THESE WINDS WILL ADVECT LOW LEVEL MOISTURE AND INCREASE INSTABILITY OVER THE NW GULF RESULTING IN SCATTERED SHOWERS AND TSTMS NEAR THE TEXAS AND LOUISIANA COASTS THROUGH SUNDAY. CARIBBEAN SEA... A 1032 MB SURFACE HIGH CENTERED OVER THE W ATLC NEAR 34N69W IS MAINTAINING FRESH TO STRONG TRADE WINDS ACROSS THE CARIBBEAN SEA. THE STRONGEST WINDS ARE FOUND NEAR THE COAST OF COLOMBIA... WHERE E TO NE SURFACE WINDS UP TO 30 KT ARE OCCURRING. A BROAD UPPER LEVEL RIDGE ENCOMPASSES THE CARIBBEAN SEA AND OVERALL ATMOSPHERIC STABILITY IS ASSOCIATED WITH THIS RIDGE RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. HOWEVER...THE TRADE WINDS ARE ADVECTING POCKETS OF LOW LEVEL MOISTURE WITH ISOLATED SHOWERS WESTWARD ACROSS THE CARIBBEAN. THE GREATEST CONCENTRATION OF THESE SHOWERS ARE LOCATED OVER PUERTO RICO AND JAMAICA. ALSO... UPPER LEVEL MOISTURE AND HIGH LEVEL CLOUDS CONTINUE TO STREAM NORTHEASTWARD ACROSS THE WRN CARIBBEAN...WITH UPPER LEVEL DIVERGENCE SUPPORTING SCATTERED SHOWERS OVER THE GULF OF HONDURAS S OF 17N W OF 85W...INCLUDING INLAND HONDURAS AND NICARAGUA. ATLANTIC OCEAN... A DEEP LAYER TROUGH OVER THE WRN AND CENTRAL ATLC IS ASSOCIATED WITH A SURFACE COLD FRONT THAT EXTENDS FROM NE OF THE DISCUSSION AREA TO 32N53W TO 27N60W AND CONTINUES AS A SURFACE STATIONARY FRONT TO 26N70W. LOW LEVEL CONVERGENCE IS RESULTING IN SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THESE FRONTS. THIS ACTIVITY IS ALSO BEING SUPPORTED BY UPPER LEVEL DIVERGENCE IN THE NE QUADRANT OF A 75-85 KT UPPER LEVEL WIND SPEED MAXIMUM OVER THE SW NORTH ATLC. TO THE W OF THE FRONTS...DEEP LAYER DRY AIR AND SUBSIDENCE ASSOCIATED WITH A 1032 MB SURFACE HIGH NEAR 34N69W ARE RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. FARTHER TO THE E...SUBSIDENCE IN THE VICINITY OF A SURFACE RIDGE IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE CENTRAL AND E ATLC. HOWEVER...ATMOSPHERIC INSTABILITY AND UPPER LEVEL DIVERGENCE IN THE VICINITY OF A SHARP UPPER LEVEL TROUGH WITH AN AXIS EXTENDING FROM 7N41W TO 20N37W TO 31N25W IS RESULTING IN SCATTERED SHOWERS N OF 23N BETWEEN 20W-28W. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS PRESENT WITH AN AXIS EXTENDING FROM 10N14W TO 3N33W. UPPER LEVEL DIVERGENCE IN THE VICINITY OF THIS UPPER LEVEL RIDGE IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ HUFFMAN