000 AXNT20 KNHC 231746 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED MAY 23 2012 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1700 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 12N30W TO 5N31W MOVING W AT 15-20 KT. THE WAVE COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. NO DEEP CONVECTION IS CURRENTLY NEAR THE WAVE LIKELY DUE TO AFRICAN DUST BOTH TO THE N AND W OF THE AXIS. A TROPICAL WAVE EXTENDS FROM 12N51W TO 7N53W MOVING W NEAR 10 KTS. OVER THE PAST DAY OR SO THE WAVE WAS INTERACTING WITH AN UPPER LEVEL TROUGH THAT IS NOW OVER THE CENTRAL ATLC. THIS INTERACTION CAUSED THE WAVE TO SLOW DOWN ITS WWD MOTION AS WELL AS WEAKEN IT. THE CURRENT LOCATION IS SOMEWHAT DIFFICULT TO DISCERN. THE WAVE REMAINS EMBEDDED WITHIN AN AREA OF MAXIMUM MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 7N-9N BETWEEN 49W-54W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF GUINEA AT 10N14W CONTINUING OVER THE E ATLC WATERS ALONG 6N19W 6N27W. THE ITCZ BEGINS NEAR 5N34W AND CONTINUES ALONG 5N44W 8N51W. ...DISCUSSION... THE GULF OF MEXICO... DRY AIR ALOFT IN MAINLY ZONAL WLY FLOW IS PROVIDING FAIR CONDITIONS ACROSS MUCH OF THE GULF OF MEXICO TODAY. SURFACE RIDGING AROUND A 1014 MB HIGH AT 27N90W IS ALSO CONTRIBUTING TO THE FAIR WEATHER. LIGHT ANTI-CYCLONIC FLOW IS AROUND THE HIGH CENTER WITH STRONGER WINDS ALONG THE TEXAS COAST. AN UPPER LEVEL TROUGH TO THE N OVER THE ERN CONUS SUPPORTS A WEAK STATIONARY FRONT THAT LINES THE NE GULF COAST ALONG 31N85W 30N89W 31N94W. A FEW ISOLATED SHOWERS ARE ALONG THE AXIS. MOISTURE ASSOCIATED WITH AN AREA OF LOW PRESSURE IN THE NW CARIBBEAN STILL EMERGES SLIGHTLY INTO THE FAR SE GULF. NO SHOWERS OR THUNDERSTORMS ARE PRESENT IN THE BASIN AT THIS TIME...BUT COULD BE POSSIBLE ESPECIALLY OVER THE FLORIDA STRAITS AND S FLORIDA. THE SYSTEM IN THE NW CARIBBEAN IS EXPECTED TO MOVE N OR NE AND COULD CONTINUE TO IMPACT THE SE GULF OVER THE NEXT COUPLE OF DAYS. WEAK SURFACE RIDGING WILL CONTINUE ACROSS THE REMAINDER OF THE BASIN. THE CARIBBEAN SEA... BROAD CYCLONIC SURFACE FLOW COVERS THE NW CARIBBEAN AROUND A 1009 MB LOW NEAR 20N84W. A SURFACE TROUGH EXTENDS THROUGH THE LOW CENTER FROM E OF FLORIDA AT 25N80W ACROSS CUBA AT 23N81W TO THE LOW CENTER AT 20N84W AND CONTINUING TOWARDS THE S AND INTO HONDURAS AT 15N87W. THIS AREA ALSO LIES UNDERNEATH DIFFLUENCE ALOFT BETWEEN A BROAD UPPER LEVEL TROUGH OVER THE ERN CONUS AND AN UPPER LEVEL RIDGE EXTENDING FROM NICARAGUA ACROSS HISPANIOLA AND INTO THE W ATLC. THIS PATTERN IS HELPING PRODUCE NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS MAINLY E OF THE SURFACE TROUGH FROM 15N-23N BETWEEN 78W-82W. THIS SYSTEM IS EXPECTED TO MOVE N OR NE OVER THE NEXT SEVERAL DAYS. THE ERN CARIBBEAN IS EXPERIENCING MOSTLY FAIR WEATHER DUE TO DRY AIR ALOFT AROUND THE E SIDE OF THE AFOREMENTIONED UPPER LEVEL RIDGE. TRADEWIND FLOW OF 15-20 KTS COVERS MUCH OF THE BASIN BESIDES NEAR THE AREA OF LOW PRESSURE IN THE WRN GULF. A FEW SHOWERS/POSSIBLE THUNDERSTORMS ARE ALSO IMPACTING THE SRN WINDWARD ISLANDS DUE TO SOME MOISTURE THAT HAS MOVED W FROM THE TROPICAL ATLC. EXPECT MOIST CONDITIONS TO REMAIN OVER THE WRN GULF FOR THE NEXT SEVERAL DAYS WITH POSSIBLE SHOWERS/THUNDERSTORMS TO CONTINUE IN THE SE CARIBBEAN. THE ATLANTIC OCEAN... DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE ERN CONUS AND AN UPPER LEVEL RIDGE EXTENDING FROM THE CARIBBEAN ACROSS HISPANIOLA TO 39N53W IS SUPPORTING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF CUBA TO 27N BETWEEN 74W-80W...AND N OF 27N BETWEEN 66W-79W. A SURFACE TROUGH EXTENDING FROM THE W ATLC ACROSS CUBA TO NEAR 25N80W MAY ALSO BE SUPPORTING SOME OF THE ACTIVITY. THE UPPER RIDGE SUPPORTS BROAD SURFACE RIDGING AROUND A 1028 MB HIGH NEAR 36N46W. HOWEVER...AN UPPER LEVEL TROUGH OVER THE NE ATLC THAT EXTENDS INTO THE CENTRAL TROPICAL ATLC FROM THE AZORES ISLANDS TO 13N43W SUPPORTS A STATIONARY FRONT THAT EXTENDING INTO THE SURFACE RIDGE ALONG 31N25W 28N37W 31N48W. ISOLATED SHOWERS ARE WITHIN 50 NM EITHER SIDE OF THE AXIS. AN UPPER LEVEL RIDGE COVERS THE ERN TROPICAL ATLC CENTERED NEAR 16N23W. VISIBLE SATELLITE IMAGERY ALONG WITH GOES-R DUST ENHANCEMENT IMAGERY INDICATES THAT AN AREA OF DUST EXTENDS FROM THE COAST OF AFRICA TO 50W WITH CLEARING AROUND THE TROPICAL WAVE NEAR IN THE CENTRAL TROPICAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON