000 AXNT20 KNHC 082344 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAY 08 2011 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2300 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED FROM NRN LIBERIA NEAR 7N12W ALONG 5N20W CROSSING THE EQUATOR NEAR 30W CONTINUING TO NRN BRAZIL NEAR 1S46W. STRONG CONVECTION IS WITHIN 150 NM S OF THE AXIS BETWEEN 11W-19W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM EQ-4N BETWEEN 23W-35W. SIMILAR ACTIVITY IS WITHIN 230 NM S OF THE AXIS BETWEEN 28W-42W. ...DISCUSSION... GULF OF MEXICO... THE GULF OF MEXICO IS EXPERIENCING MOSTLY FAIR WEATHER UNDER THE INFLUENCE OF SURFACE RIDGING AROUND A 1017 MB HIGH CENTERED OFF THE W COAST OF FLORIDA NEAR 27N86W. LIGHT ANTI-CYCLONIC FLOW IS AROUND THE HIGH WITH SE-S WINDS OF 10-15 KTS ACROSS THE FAR WRN GULF. ALOFT...BROAD UPPER LEVEL RIDGING IS ACROSS THE BASIN WITH AXIS EXTENDING FROM THE YUCATAN PENINSULA TO THE MISSISSIPPI VALLEY. SWLY FLOW ALOFT AROUND THE WRN SIDE OF THE UPPER RIDGE IS DRAWING MOISTURE FROM THE E PAC INTO THE WRN GULF SUPPORTING AREAS OF HIGH CLOUDS. THE REMAINDER OF THE BASIN IS ESSENTIALLY CLOUD FREE. EXPECT LITTLE CHANGE OVER THE NEXT SEVERAL DAYS. CARIBBEAN SEA... THE NW CARIBBEAN IS EXPERIENCING MOSTLY FAIR CONDITIONS INFLUENCED BY SURFACE RIDGING EXTENDING FROM THE GULF OF MEXICO AS WELL AS DRY AIR ALOFT THAT IS COVERING THE NRN HALF OF THE CARIBBEAN IN ZONAL WLY FLOW. HOWEVER...THE SW CARIBBEAN IS UNDER MORE MOIST CONDITIONS WITH TOTAL PRECIPITABLE WATER IMAGERY INDICATING MAXIMUM MOISTURE VALUES IN THIS AREA. SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS ARE S OF 11N BETWEEN 76W-85W INCLUDING THE MAJORITY OF COSTA RICA AND PANAMA. SCATTERED SHOWERS ARE ALSO OVER PORTIONS OF HONDURAS AND NICARAGUA. MOISTURE ALOFT IS ALSO BEING DRAWN ACROSS THE SRN CARIBBEAN SUPPORTING HIGH CLOUDS. ACROSS THE ERN CARIBBEAN...A SHEAR AXIS EXTENDS FROM THE ATLC TO THE LEEWARD ISLANDS NEAR ANTIGUA. TOTAL PRECIPITABLE WATER IMAGERY ALSO SHOWS A LINE OF ENHANCED MOISTURE CONTINUING FROM THE LEEWARD ISLANDS ALONG 16N. SCATTERED SHOWERS ARE NOTED FROM 16N-19N E OF 70W. EXPECT LITTLE CHANGE OVER THE NEXT 24 HRS. ATLANTIC OCEAN... WHILE MUCH OF THE SW N ATLC IS UNDER FAIR CONDITIONS THIS EVENING INFLUENCED BY DRY AIR ALOFT AND SURFACE RIDGING CENTERED OVER OF THE ERN GULF OF MEXICO...A COLD FRONT ENTERS THE DISCUSSION AREA NEAR 32N62W CONTINUING S THEN W ALONG 28N64W 26N74W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 NM AHEAD OF THE FRONT. THE SYSTEM IS SUPPORTED BY AN UPPER LEVEL TROUGH EXTENDING FROM MASSACHUSETTS TO NEAR 31N59W. AN UPPER LEVEL RIDGE IS BETWEEN 33W-55W SUPPORTING FAIR WEATHER. A SECOND LOW PRESSURE SYSTEM IS OVER THE E CENTRAL ATLC WITH AN OCCLUDED 1004 MB SURFACE LOW CENTERED NEAR 34N40W. A PAIR OF SURFACE TROUGHS EXTEND INTO THE DISCUSSION AREA ASSOCIATED WITH THIS SYSTEM. THE OUTERMOST TROUGH EXTENDS ALONG 31N33W 22N36W 17N46W CONTINUING AS A SHEARLINE TO THE LEEWARD ISLANDS NEAR 17N62W. SCATTERED SHOWERS ARE WITHIN 120 NM E OF THE TROUGH E OF 37W...AND WITHIN 60 NM EITHER SIDE OF THE AXIS OF THE REMAINDER OF THE TROUGH AND THE SHEARLINE W OF 37W. THE SECOND SURFACE TROUGH EXTENDS FROM THE LOW CENTER ALONG 31N37W 27N39W 24N43W. ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF THE AXIS. THIS SYSTEM IS SUPPORTED BY AN UPPER LEVEL CUT-OFF LOW NEAR 36N40W. THE REMAINDER OF THE E ATLC IS EXPERIENCING FAIR CONDITIONS INFLUENCE BY SURFACE RIDGING AROUND A 1020 MB HIGH NEAR 34N20W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON