000 AXNT20 KNHC 011130 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUN 01 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS LOCATED OVER THE SE CARIBBEAN ALONG 62W S OF 14N MOVING W 15-20 KT. THIS WAVE IS ASSOCIATED WITH A NARROW MAXIMUM IN TOTAL PRECIPITABLE WATER AHEAD OF DRY LOW-MID LEVEL AIR IN PART ASSOCIATED WITH SAHARAN DUST. THE POSITION OF THE WAVE IS BASED MAINLY ON THIS TPW FIELD...AS LITTLE SIGNATURE IS APPARENT IN THE LOW-MID LEVEL CLOUDS OR IN SFC OBSERVATIONS. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N11W 3N23W 2N34W 1N45W TO THE EQUATOR ALONG 50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 2N-7N BETWEEN 10W-22W. SIMILAR CONVECTION IS S OF 6N BETWEEN 24W-34W. SCATTERED MODERATE CONVECTION IS S OF 3N BETWEEN 35W-49W. ...DISCUSSION... GULF OF MEXICO... A SURFACE TROUGH REPRESENTING THE REMNANTS OF A FRONT IS MEANDERING OVER THE SE AND S CENTRAL GULF FROM NEAR FORT MYERS FLORIDA TO 25N87W TO JUST W OF THE NW CORNER OF THE YUCATAN PENINSULA. LOW LEVEL CONVERGENCE IS SUPPORTING ISOLATED SHOWERS AND TSTMS ALONG AND S OF THE TROUGH. SUBSIDENCE ASSOCIATED WITH WEAK SURFACE HIGH PRESSURE OVER THE N WATERS IS RESULTING IN GENERALLY FAIR WEATHER...WHERE LIGHT WINDS PERSIST. SOUTHWESTERLY FLOW ALOFT CONTINUES TO ADVECT MOISTURE OVER THE WESTERN WATERS...WHERE HIGH LEVEL CLOUDINESS IS INCREASING. IR IMAGERY AND LIGHTNING DATA SHOW SOME TSTM ACTIVITY JUST OFF THE COAST OF MEXICO FROM 21N-23N W OF 96W. LOOKING AHEAD A DAY OR TWO...NWP MODELS SUGGEST THAT THE OLD FRONT WILL GRADUALLY DISSIPATE ALLOWING SFC RIDGING TO BECOME BETTER ESTABLISHED ACROSS THE AREA. CARIBBEAN SEA... THE MID-UPPER PATTERN IS QUITE AMPLIFIED OVER THE CARIBBEAN WITH A RIDGE OVER THE WRN HALF AND TROUGHING OVER THE ERN HALF. DIFFLUENCE ALOFT COUPLED WITH LOW-LEVEL CONVERGENCE ALONG AN OLD FRONT OVER THE SE GULF OF MEXICO IS PRODUCING SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE YUCATAN PENINSULA...YUCATAN CHANNEL...AND W CUBA. SIMILAR ACTIVITY IS OCCURRING OVER PORTIONS OF CENTRAL AMERICA ENHANCED BY THE ITCZ. THE ATMOSPHERE IS MORE STABLE OVER THE CENTRAL CARIBBEAN IN AN UPPER CONFLUENT AREA BETWEEN THE TROUGH AND RIDGE. SW FLOW ALOFT E OF THE TROUGH AXIS IS ADVECTING MOISTURE ACROSS THE SE CARIBBEAN... BUT IT IS NOT RESULTING IN ANY SIGNIFICANT SHOWER OR TSTM ACTIVITY. IN THE LOWER LEVELS...SHORTWAVE IR IMAGERY...SFC OBS...AND QUIKSCAT DATA SHOW EVIDENCE OF A WEAK TROUGH OVER AND N OF THE VIRGIN ISLANDS. THIS WEAK FEATURE IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS IN ITS VICINITY. TRADE WINDS REMAIN 20-30 KT ACROSS THE S CENTRAL PORTION DUE TO THE PRESSURE GRADIENT BETWEEN A HIGH OVER THE SUBTROPICAL CENTRAL ATLC AND LOWER PRES OVER NRN SOUTH AMERICA. WINDS NEAR 20 KT EXIST OVER THE TOPOGRAPHICALLY ENHANCED GULF OF HONDURAS. LITTLE CHANGE IN THESE FLOWS ARE FORECAST OVER THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... WEATHER CONDITIONS ACROSS MUCH OF THE ATLC DISCUSSION ZONE ARE QUIET...WITH ONLY A FEW AREAS OF UNSETTLED WEATHER TO MENTION. SCATTERED SHOWERS AND ISOLATED TSTMS ARE LOCATED OVER THE WRN BAHAMAS ASSOCIATED WITH AN UPPER JET AND AN OLD FRONTAL BOUNDARY. THE ASSOCIATED THINNING DEBRIS MOISTURE HAS SPREAD WELL TO THE NE THRU BERMUDA BY STRONG SW FLOW ALOFT. HIGHLY AMPLIFIED DEEP LAYER RIDGING DOMINATES THE CENTRAL ATLC...THOUGH AN UPPER LOW AND SFC TROUGH NEAR THE VIRGIN ISLANDS ARE INTERRUPTING THE RIDGE SLIGHTLY. NONETHELESS...FAIR WEATHER DOMINATES THE MAJORITY OF THE REGION WITH THE EXCEPTION OF NEAR THE SFC TROUGH...S OF 22N BETWEEN 61W-67W WHERE SCATTERED SHOWERS AND ISOLATED TSTMS ARE LIKELY. THE E ATLC IS MAINLY UNDER AN UPPER TROUGH WITH A RELATED FRONT NEARING THE N BORDER AND A WEAK SFC TROUGH S OF IT EXTENDING FROM 31N24W TO 25N29W. LITTLE SIGNIFICANT SHOWER ACTIVITY IS ALONG THE BOUNDARY. IN FACT...CONVECTION OVER THE E ATLC APPEARS CONFINED TO THE ITCZ. $$ CANGIALOSI