000 AXNT20 KNHC 270543 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE JUL 27 2010 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0530 UTC. ...TROPICAL WAVES... ELONGATED TROPICAL WAVE IS ALONG 19N27W 13N32W 6N34W MOVING W 5 TO 10 KT. WELL DEFINED LOW TO MID LEVEL CYCLONIC FLOW SURROUNDS THE WAVE AXIS EVIDENT IN BOTH SATELLITE DATA AND SATELLITE DERIVED WINDS. THE WAVE ALSO COINCIDES WITH A SURGE IN DEEP LAYER MOISTURE SEEN IN TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...THIS WAVE IS FOUND WITHIN A BROAD AREA OF SIGNIFICANT SAHARAN AIR LAYER SUPPRESSING ANY DEEP CONVECTION FROM DEVELOPING. TROPICAL WAVE IS ABOUT 180 NM EAST OF THE LESSER ANTILLES ALONG 57W S OF 18N MOVING WEST 5 TO 10 KT. THIS WAVE REMAINS ATTACHED TO THE ITCZ WITH VERY WEAK LOW-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE AXIS. THE WAVE ALSO LIES AHEAD OF A SURGE IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. VERY DRY AND STABLE AIR ALOFT IS OVERHEAD THIS WAVE. THEREFORE...ONLY SCATTERED WEAK CONVECTION IS IN THE FAR SOUTHERN EXTENSION OF THE WAVE LINKED TO THE ITCZ. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED FROM THE WESTERN AFRICAN COAST OF THE GAMBIA NEAR 13N16W...WESTWARD ALONG 14N20W 17N27W 8N35W 7N50W 10N60W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 190 NM ON EITHER SIDE OF THE ITCZ FROM 35W TO 60W. ISOLATED MODERATE CONVECTION IS OVER THE COASTAL WATERS OF GUINEA AND GUINEA-BISSAU TO 200 NM OFFSHORE. ...DISCUSSION... GULF OF MEXICO... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ACROSS MOST OF THE EASTERN HALF...FROM 23N TO 27N BETWEEN 84W AND 91W...AND THE NORTH CENTRAL GULF...NORTH OF 27N BETWEEN 81W AND 94W...ENHANCED BY BROAD CYCLONIC CIRCULATION AROUND A MID/UPPER LEVEL LOW CENTERED NEAR 28N88W. STRONGER CONVECTION IS OBSERVED OVER THE EASTERN BAY OF CAMPECHE...SOUTH OF 21N EAST OF 94W...AND THE NORTHERN YUCATAN PENINSULA COAST TO 80 NM OFFSHORE...PRODUCED BY A SURFACE TROUGH ALONG 92W SOUTH OF 22N. THIS TROUGH WILL CONTINUE TO MOVE WEST WITH CONVECTION OVER THE NEXT DAY OR SO. AN UPPER LOW CENTERED OVER NORTHERN TEXAS EXTENDS AN UPPER TROUGH INTO THE NW GULF GENERATING SCATTERED SHOWERS AND THUNDERSTORM ACROSS THE COASTAL WATERS OF TEXAS TO 30 NM OFFSHORE. COMPUTER MODELS INDICATE MORE CONVECTION WILL DEVELOP ALONG THE TEXAS COAST OVER THE NEXT FEW DAYS AS THE UPPER LOW OVER NORTHERN TEXAS LINGERS OVER THIS REGION. CARIBBEAN SEA... SCATTERED SHOWERS AND THUNDERSTORMS ARE OVER THE FAR SW CARIBBEAN...WEST OF 74W SOUTH OF 12N...DUE TO THE PACIFIC ITCZ EXTENDING ACROSS THE CENTRAL AMERICAN COUNTRIES OF COSTA RICA AND PANAMA TO NORTHERN COLOMBIA. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS LINGER OVER THE COASTAL WATERS OF THE EASTERN YUCATAN PENINSULA...BELIZE...HONDURAS...AND NICARAGUA TO 100 NM OFFSHORE...FROM MID/UPPER LEVEL TROUGHINESS THAT MOVED OVER THE WESTERN CARIBBEAN 24 HOURS AGO. STRONG SUBSIDENCE ALOFT ALONG WITH SAHARAN DUST IS ELSEWHERE ACROSS THE REGION...PROVIDING FAIR WEATHER CONDITIONS ACROSS THE REMAINDER OF THE CARIBBEAN. ATLANTIC OCEAN... NO SIGNIFICANT WEATHER IS OCCURRING ACROSS THE ATLANTIC DUE TO DRY SAHARAN AIR ACROSS THE TROPICAL ATLC INTO THE CARIBBEAN AND SURFACE RIDGING DOMINATING THE AREA OF DISCUSSION ANCHORED BY A 1020 MB HIGH CIRCULATING OVER WESTERN ATLANTIC NEAR 27N74W AND A BROAD 1025 MB HIGH WEST OF THE AZORES NEAR 37N31W PROVIDING FAIR WEATHER CONDITIONS ACROSS THE AREA. COMPUTER MODELS CONTINUE THIS TREND FOR AT LEAST THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA