000 AXNT20 KNHC 051048 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON AUG 05 2013 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... A TROPICAL WAVE AXIS EXTENDS FROM 27N45W TO 18N47W MOVING W-NW NEAR 15 KT AROUND THE SW PERIPHERY OF A SURFACE RIDGE. THE TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT. METEOSAT-9 SAL TRACKING PRODUCT CONTINUES TO SHOW SOME DRY AIR SPREADING OVER THE WAVE ENVIRONMENT WHICH ALONG WITH STRONG WIND SHEAR IS SUPPRESSING CONVECTION. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE WEST AFRICAN COAST NEAR 10N14W TO 09N22W 10N31W. THE INTERTROPICAL CONVERGENCE ZONE AXIS STARTS NEAR 10N31W AND CONTINUES ALONG 12N40W TO 09N50W 05N53W. SCATTERED MODERATE CONVECTION IS WITHIN 170 NM EITHER SIDE OF THE MONSOON TROUGH AXIS. SIMILAR CONVECTION IS FROM 06N-12N BETWEEN 40W-50W AS WELL AS WITHIN 70 NM EITHER SIDE OF THE ITCZ AXIS W OF 50W. ...DISCUSSION... THE GULF OF MEXICO... AS OF 0900 UTC...ANTICYCLONIC FLOW IN THE RANGE OF 5-10 KT SPREADS ACROSS THE BASIN N OF 22N ANCHORED BY A 1017 MB HIGH NEAR 26N89W BEING SUPPORTED BY A BROAD MIDDLE TO UPPER LEVEL RIDGE. DRY AIR IN THE LOWER AND MIDDLE LEVELS IS SUPPORTING FAIR WEATHER ACROSS MOST OF THE GULF THIS MORNING. A SURFACE TROUGH IS OVER THE BAY OF CAMPECHE EXTENDING FROM 22N90W TO 18N93W AND ENHANCING SCATTERED MODERATE CONVECTION/TSTMS S OF 20N W OF 94W. THE CENTER OF HIGH PRESSURE IS EXPECTED TO PERSIST DURING THE NEXT 48 HOURS. RAINSHOWERS IN THE NE GULF ASSOCIATED WITH THE FRONTAL SYSTEM UP NORTH ARE LIKELY TO CONTINUE. RAINSHOWERS ARE ALSO EXPECTED IN THE BAY OF CAMPECHE AS A SURFACE TROUGH MOVES IN THE AREA. THE CARIBBEAN SEA... EXCEPT FOR THE FAR WESTERN CARIBBEAN...THE WINDWARD PASSAGE AND THE SOUTHERN CARIBBEAN...VERY DRY AIR FROM A SAHARAN OUTBREAK SPREADS ACROSS THE BASIN IN THE LOWER AND MIDDLE LEVELS WHICH IS FAVORING FAIR WEATHER. SURFACE RIDGING IS ACROSS THE CARIBBEAN WITH TRADEWINDS RANGING FROM 20-25 KT OVER THE CENTRAL-SOUTHERN BASIN AND 5-15 KT ELSEWHERE. ISOLATED MODERATE CONVECTION/TSTMS ARE WITHIN 200 NM OF THE COAST OF NICARAGUA BEING SUPPORTED BY HIGH LOW LEVEL MOISTURE AND UPPER LEVEL DIVERGENCE. SIMILAR CONVECTION IS S OF 11N ASSOCIATED WITH THE MONSOON TROUGH AXIS. UPPER LEVEL DIFFLUENCE FROM THE BROAD UPPER HIGH CENTERED OVER LOUISIANA AND THE LOW NE OF THE HISPANIOLA IS ENHANCING ISOLATED SHOWERS BETWEEN SE CUBA AND JAMAICA. SIMILAR CONVECTION IS OVER THE W CARIBBEAN S OF 18N W OF 85W DUE TO UPPER LEVEL DIVERGENCE. DRY AIR IS EXPECTED TO PERSIST OVER MOST OF THE BASIN WITHIN THE NEXT 48 HOURS SUPPORTING FAIR WEATHER. A TROPICAL WAVE WILL ENTER THE EASTERN CARIBBEAN TUESDAY. HISPANIOLA... CURRENTLY VERY DRY AIR IS ACROSS THE ISLAND SUPPORTING FAIR WEATHER. A DRY AIRMASS WILL BE MOVING ACROSS THE ISLAND EARLY TODAY AND CLEAR SKIES WILL PERSIST. HOWEVER...SHOWERS AND TSTMS ARE EXPECTED IN THE AFTERNOON/EARLY EVENING ENHANCED BY DAYTIME HEATING AND AN UPPER LEVEL LOW CENTERED NE OF THE ISLAND IN THE ATLC. THE ATLANTIC OCEAN... BESIDES THE TROPICAL WAVE ALREADY DISCUSSED...A PREFRONTAL TROUGH ENTERS THE AREA OF DISCUSSION IN THE W ATLC NEAR 30N69W TO 23N77W. SCATTERED MODERATE CONVECTION AND TSTMS ARE N OF 27N W OF 71W AS WELL AS 80 NM E OF THE TROUGH AXIS N OF 28N. ANOTHER SURFACE TROUGH EXTENDS AHEAD OF THE TROPICAL WAVE FROM 28N50W TO 22N52W WITH NO CONVECTION ASSOCIATED WITH IT. OTHERWISE...SURFACE RIDGING AND FAIR WEATHER SUPPORTED BY LOWER- MIDDLE LEVEL DRY AIR ARE ACROSS THE REMAINDER BASIN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR