000 AXNT20 KNHC 270002 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAY 26 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 2330 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 70W S OF 14N MOVING W 15-20 KT. WAVE POSITION BASED ON PROPAGATION CONTINUITY AS IT REMAINS DIFFICULT TO DEPICT ON SATELLITE IMAGERY. TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS SHOWS DECREASING MOISTURE AS THE WAVE CONTINUES WESTWARD ACROSS NORTHERN VENEZUELA. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N12W 5N20W 1N30W CROSSING THE EQUATOR NEAR 34W AND INTO NE BRAZIL NEAR 2S45W. ISOLATED MODERATE CONVECTION IS WITHIN 30 NM OF THE AXIS BETWEEN 19W-26W. A LARGE CLUSTER OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 5S-3N BETWEEN 26W-35W. ...DISCUSSION... GULF OF MEXICO... SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE TO IMPACT THE NE GULF THIS EVENING. AN UPPER LEVEL TROUGH PRESENT ACROSS THE NE GULF EXTENDS OVER FLORIDA AND INTO THE W ATLC. ASSOCIATED DIFFLUENCE IN THE MID AND UPPER LEVELS COMBINED WITH LOW-LEVEL MOISTURE CONVERGENCE IS SUPPORTING THIS CONVECTIVE ACTIVITY N OF 26N AND E OF 87W. SCATTERED SHOWERS MOVING OFF THE TEXAS COAST CONTINUE TO DISSIPATE ACROSS THE NW GULF AS THEY ENCOUNTER DRIER AIR ALOFT IN THE SUBSIDENT ATMOSPHERE ON THE BACK SIDE OF THE AFOREMENTIONED UPPER TROUGH. ACROSS THE SRN GULF... DEEP LAYER DRY AIR IN WLY FLOW ALOFT IS SUPPORTING GENERALLY FAIR WEATHER. LIGHT SLY RETURN FLOW IS OBSERVED ACROSS THE SW GULF AND BAY OF CAMPECHE. AREAS OF SMOKE AND HAZY CONDITIONS S OF 25N W OF 86W ARE A RESULT OF WILDFIRES ACROSS SRN MEXICO AND THE YUCATAN PENINSULA. CARIBBEAN SEA... HIGH PRESSURE IN THE W ATLC IS MAINTAINING STRONG E TO SE WIND FLOW ACROSS THE CARIBBEAN. THE SOUTHEASTERLY FLOW IS GENERATING AFTERNOON SHOWERS AND THUNDERSTORMS ACROSS THE GREATER ANTILLES AND NORTHERN LEEWARD ISLANDS.THIS ACTIVITY IS BEING SUPPORTED BY UPPER LEVEL DIVERGENCE AND DEEP LAYER MOISTURE NEAR AND TO THE EAST OF THE BASE OF AN UPPER LEVEL TROUGH EXTENDING FROM THE ERN GULF OF MEXICO TO THE BAHAMAS. AN UPPER LEVEL DIFFLUENT PATTERN AROUND AN UPPER HIGH OVER THE EAST PACIFIC IS GENERATING ISOLATED SHOWERS AND THUNDERSTORMS IN THE SW CARIBBEAN S OF 12N. THE NW CARIBBEAN REMAINS RELATIVELY CLEAR UNDER MODERATE SUBSIDENCE ALOFT. IN ADDITION...A TROPICAL WAVE IS OVER THE S/CENTRAL CARIBBEAN ALONG 70W. PLEASE SEE TROPICAL WAVE SECTION ABOVE FOR FURTHER INFORMATION. ATLANTIC OCEAN... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OBSERVED ALONG A SURFACE TROUGH THAT EXTENDS FROM 32N77W INTO A 1010 MB LOW NEAR 31N75W AND CONTINUES TO 26N74W. THIS CONVECTION IS BEING ENHANCED BY UPPER LEVEL DIVERGENCE ALONG THE LEADING EDGE OF AN UPPER TROUGH. THE LOW AND ASSOCIATED SFC TROUGH ARE FORECAST TO MOVE NORTH OF THE DISCUSSION AREA OVER THE NEXT 24 HOURS. ADDITIONAL CONVECTION IS FLARING UP OVER THE EASTERN BAHAMAS AT THE EXIT REGION OF A WEAK WESTERLY JET ALONG THE BASE OF THE AFOREMENTIONED TROUGH. FURTHER EAST...A 1023 MB SFC HIGH IS CENTERED NEAR 31N62W. THE PRESENCE OF THIS HIGH PRESSURE IS LIMITING THE SOUTHWARD EXTEND OF A COLD FRONT NORTH OF THE REGION. STRONG SUBSIDENCE IS MAINTAINING FAIR WEATHER IN THE VICINITY OF THIS HIGH. UPPER LEVEL TROUGHING IS PRESENT ACROSS THE CENTRAL ATLC. AN ASSOCIATED WEAK 1019 MB SURFACE LOW IS CENTERED NEAR 29N50W...HOWEVER...LITTLE CONVECTION IS OBSERVED. A SURFACE RIDGE IS PRESENT ACROSS THE E ATLC. UPPER LEVEL DIVERGENCE ASSOCIATED WITH AN UPPER HIGH NEAR 5N30W IS ENHANCING CONVECTION ALONG THE ITCZ. $$ WADDINGTON