000 AXNT20 KNHC 142323 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN JUN 14 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 2245 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 71W S OF 19N MOVING W AROUND 15 KT. THIS WAVE COINCIDES WITH A RELATIVELY HIGHLY-AMPLIFIED MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SURFACE OBSERVATIONS OVER THE DOMINICAN REPUBLIC AND COMPUTER MODEL GUIDANCE INDICATE CYCLONIC CURVATURE IN THE LOW LEVEL FLOW ACROSS THIS WAVE. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 9N-12N BETWEEN 68W-71W INCLUDING PORTIONS OF NW VENEZUELA. SCATTERED MODERATE CONVECTION IS FROM 18N-19N BETWEEN 69W-71W INCLUDING PORTIONS OF HISPANIOLA. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N16W 7N22W 3N30W 2N40W 2N51W. SCATTERED MODERATE CONVECTION IS FROM 4N-11N BETWEEN 19W-24W. SCATTERED MODERATE CONVECTION IS ALSO S OF 3N BETWEEN 36W-45W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYER DRY AIR AND SUBSIDENCE IN NORTHERLY FLOW ALOFT COVER MUCH OF THE GULF REGION...WHERE GENERALLY FAIR WEATHER IS PRESENT. THE SUBSIDENCE IS SUPPORTING A 1019 MB SURFACE HIGH OVER THE CENTRAL GULF NEAR 28N88W. ANTICYCLONIC FLOW AROUND THE SURFACE HIGH IS AFFECTING MUCH OF THE GULF...WITH SE WINDS OF 15 TO 20 KT OCCURRING ACROSS PORTIONS OF THE W GULF IN RESPONSE TO A BROAD SURFACE TROUGH OVER MEXICO AND THE SOUTHERN PLAINS OF THE UNITED STATES. LITTLE CHANGE IN THIS OVERALL PATTERN IS EXPECTED ACROSS MUCH OF THE GULF DURING THE NEXT FEW DAYS. HOWEVER...A SURFACE TROUGH IS FORECAST TO MOVE WESTWARD ACROSS THE S GULF FOR TUESDAY AND WEDNESDAY... ACCOMPANIED BY SCATTERED THUNDERSTORMS. CARIBBEAN SEA... AN UPPER LEVEL TROUGH IS OVER THE FAR NW CARIBBEAN WITH AN AXIS EXTENDING FROM 22N85W TO 16N91W AND EXTENDING SOUTHWESTWARD INTO THE E PACIFIC REGION. THIS UPPER LEVEL TROUGH IS ASSOCIATED WITH A SURFACE TROUGH EXTENDING FROM THE E YUCATAN PENINSULA NEAR 21N87W TO NW HONDURAS NEAR 16N88W. LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS WITHIN 120 NM EITHER SIDE OF THE SURFACE TROUGH. TO THE E...A BROAD UPPER LEVEL RIDGE IS AFFECTING MUCH OF THE CARIBBEAN...WHERE DEEP LAYER MOISTURE IS PRESENT. A SECOND SURFACE TROUGH IS PRESENT OVER THE CARIBBEAN...AND EXTENDS FROM S OF CUBA NEAR 21N79W TO 14N82W TO N PANAMA NEAR 9N82W. LOW LEVEL CONVERGENCE NEAR THIS SECOND SURFACE TROUGH IS COMBINING WITH THE DEEP LAYER MOISTURE TO RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS WITHIN 180 NM EITHER SIDE OF THE SECOND SURFACE TROUGH. RECENT SURFACE OBSERVATIONS CONFIRM CYCLONIC CURVATURE IN THE LOW LEVEL FLOW ACROSS THIS TROUGH. ADDITIONALLY...ATMOSPHERIC INSTABILITY IS RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS ACROSS CUBA AND THE NEARBY COASTAL WATERS. FARTHER TO THE E...SUBSIDENCE IN NW FLOW ALOFT IS INHIBITING DEEP CONVECTION ACROSS MUCH OF THE E CARIBBEAN. ATLANTIC OCEAN... ATMOSPHERIC INSTABILITY ASSOCIATED WITH AN UPPER LEVEL TROUGH ACROSS THE SW NORTH ATLC IS SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS N OF 23N BETWEEN 68W-78W...WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS N OF 21N BETWEEN 60W-67W. FARTHER TO THE W...SUBSIDENCE IN DRY NORTHERLY FLOW ALOFT IS SUPPORTING GENERALLY FAIR WEATHER ACROSS WESTERN PORTIONS OF THE SW NORTH ATLC. HOWEVER...LOW LEVEL CONVERGENCE IS SUPPORTING INCREASED CLOUDINESS AND ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF A SURFACE TROUGH EXTENDING FROM 31N78W TO E OF THE FLORIDA PENINSULA NEAR 29N80W. ACROSS THE CENTRAL AND E ATLC...GENERALLY FAIR WEATHER IS PRESENT WHERE SUBSIDENCE IS OCCURRING NEAR A BROAD SURFACE RIDGE. THIS SURFACE RIDGE IS ASSOCIATED WITH A 1024 MB SURFACE HIGH NEAR 30N53W. HOWEVER...AN UPPER LEVEL TROUGH AXIS EXTENDS FROM 17N54W TO AN UPPER LEVEL LOW NEAR 19N52W TO A SECOND UPPER LEVEL LOW NEAR 26N47W TO 28N43W. THE NORTHERN UPPER LEVEL LOW IS ASSOCIATED WITH A 1020 MB SURFACE LOW NEAR 30N46W. THESE FEATURES ARE SUPPORTING SCATTERED SHOWERS FROM 17N-22N BETWEEN 46W-53W AND N OF 27N BETWEEN 43W-49W. ACROSS THE TROPICAL ATLC...A BROAD UPPER LEVEL RIDGE IS PRESENT WITH AN AXIS EXTENDING FROM 15N17W TO AN UPPER LEVEL HIGH NEAR 14N25W TO 7N44W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THESE FEATURES IS SUPPORTING THE CONVECTION ASSOCIATED WITH THE ITCZ...AS WELL AS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS FROM 6N-10N BETWEEN 12W-15W. $$ COHEN