000 AXNT20 KNHC 080553 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUL 08 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...TROPICAL WAVES... A TROPICAL WAVE MOVED OFF THE COAST OF WEST AFRICA EARLIER YESTERDAY. AS MODEL DATA AND WEATHER OBSERVATIONS BECAME MORE CONCLUSIVE...THE WAVE AXIS WAS ADDED TO THE 07/0000 UTC SURFACE ANALYSIS MAP EXTENDING FROM 19N19W TO THE MONSOON TROUGH AXIS NEAR 12N20W. THIS WAVE IS MOVING WEST AT ABOUT 5 KT. THE WAVE AXIS LIES ON THE WRN SIDE OF A LARGE SURGE OF DEEP LAYER MOISTURE ON TOTAL PRECIPITABLE WATER IMAGERY. CURRENTLY...THE CONVECTION THE CONVECTION IN THE SRN EXTENSION OF THE WAVE AXIS IS CONFINED TO THE MONSOON TROUGH DISCUSSED BELOW. TROPICAL WAVE MOVES ACROSS THE CENTRAL ATLC WITH AXIS ANALYZED FORM 26N51W TO 16N54W MOVING W AT 15-20 KT. THE WAVE LIES ON THE WRN SIDE OF A SURGE OF DEEP LAYER MOISTURE NOTICED ON TOTAL PRECIPITABLE WATER IMAGERY. DESPITE SAHARAN DUST EMBEDDED IN THE WAVE ENVIRONMENT...WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER LEVEL CYCLONIC CIRCULATION NEAR THE WAVE AXIS AROUND 29N52W HELPING THE WAVE TO GENERATE SOME SCATTERED SHOWERS IN THE VICINITY OF THE WAVE AXIS. TROPICAL WAVE IS MOVING INLAND ACROSS THE YUCATAN PENINSULA AND PORTIONS OF CENTRAL AMERICA WITH AXIS ANALYZED FROM 22N87W TO 14N90W MOVING W NEAR 5-10 KT. THE WAVE IS EMBEDDED IN A LARGE SURGE OF DEEP LAYER MOISTURE COVERING THE FAR WRN CARIBBEAN AND CENTRAL AMERICA. SCATTERED HEAVY RAINFALL AND THUNDERSTORM ACTIVITY COVER THE NW CARIBBEAN BASIN N OF 11N W OF 81W...AS WELL AS INLAND PORTIONS OF CENTRAL AMERICA. AREAS THAT ARE RECEIVING HEAVY RAINFALL ARE AT RISK FOR LOCALIZED FLOODING AND MUDSLIDES AND SHOULD MONITOR THE ACTIVITY ASSOCIATED WITH THE WAVE. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS SW FROM THE WEST AFRICAN COAST OF SENEGAL NEAR 14N17W ALONG 12N20W TO 9N30W...WHERE THE ITCZ AXIS CONTINUES TO 7N39W. A WEAK 1012 MB SURFACE LOW BREAKS THE ITCZ ANALYZED NEAR 7N41W. THE ITCZ REFORMS W OF THE LOW NEAR 6N44W AND CONTINUES W TO THE ERN COAST OF GUYANA NEAR 6N58W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 110-150 NM ON EITHER SIDE OF THE ITCZ AND MONSOON TROUGH W OF 23W. SIMILAR CONVECTION IS E OF 23W FROM 8N16N. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL OMEGA TYPE RIDGE COVERING MOST OF THE CENTRAL AND EASTERN CONUS THIS MORNING. THIS FEATURE IS GENERATING EASTERLY ZONAL FLOW ALOFT ACROSS THE GULF N OF 21N. THIS PATTERN IS PROVIDING FAIR WEATHER CONDITIONS AND LIGHT ANTI-CYCLONIC SURFACE FLOW AROUND A PAIR OF SURFACE HIGHS CENTERED OVER THE EASTERN BASIN NEAR 28N83W. HOWEVER... CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE NOTED ACROSS THE FAR SE GULF AND YUCATAN CHANNEL S OF 24N BETWEEN 83W-90W. THE MOISTURE AND SHOWER ACTIVITY IN THIS REGION IS ASSOCIATED TO THE PASSAGE OF A TROPICAL WAVE MOVING ACROSS INLAND PORTIONS OF THE YUCATAN PENINSULA AND CENTRAL AMERICA. A SURFACE TROUGH AXIS MOVES ACROSS THE SRN FLORIDA PENINSULA AND STRAITS. DESPITE THE LOCATION OF THE SURFACE FEATURE...THE CONVECTIVE ACTIVITY IS ACTUALLY OVER THE NW BAHAMAS. WEAK SURFACE RIDGING IS EXPECTED TO REMAIN IN PLACE OVER THE WEEKEND...WHILE MOISTURE CONVERGENCE IN THE VICINITY OF THE TROPICAL WAVE WILL BRING SHOWERS AND THUNDERSTORMS TO THE BAY OF CAMPECHE. CARIBBEAN SEA... HEAVY RAINFALL AND THUNDERSTORMS ACTIVITY COVER THE NW BASIN N OF 11N W OF 81W ASSOCIATED WITH THE PASSAGE OF A TROPICAL WAVE MOVING INLAND ACROSS THE YUCATAN PENINSULA AND PORTIONS OF CENTRAL AMERICA. SIMILAR ACTIVITY IS OVER THE SW BASIN S OF 11N W OF 75W...ASSOCIATED TO A PORTION OF THE MONSOON TROUGH AXIS EXTENDING FROM NRN COLOMBIA TO ERN PANAMA TO SRN COSTA RICA. WHILE THE RAINSHOWER ACTIVITY OVER THE NW BASIN COULD SEE SOME BREAKS IN BETWEEN...THE ACTIVITY OVER THE SW BASIN IS EXPECTED TO REMAIN CONSTANT AND SLOWLY MOVE INLAND ACROSS CENTRAL AMERICA...PROVOKING FLOODING AND POSSIBLE MUDSLIDES DURING THE NEXT DAY OR SO. FAIR WEATHER CONDITIONS ARE ELSEWHERE ACROSS THE CENTRAL AND ERN CARIBBEAN DUE TO A COMBINATION OF DRY AIR ALOFT AND SAHARAN DUST ACROSS THESE REGIONS OF THE CARIBBEAN. EASTERLY TRADEWIND FLOW OF 15-25 KT IS ACROSS MUCH OF THE BASIN REACHING TO NEAR GALE FORCE CRITERIA IN THE CENTRAL CARIBBEAN BETWEEN 72W-78W S OF 14N. ATLANTIC OCEAN... WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS THE NW BAHAMAS S OF 27N BETWEEN 75W-80W. THIS AREA OF CONVECTION IS ASSOCIATED TO BROAD TURNING AROUND A WEAK SURFACE TROUGH MOVING ACROSS SRN FLORIDA PENINSULA AND STRAITS. A TROPICAL WAVE MOVES ACROSS THE CENTRAL ATLC WITH CONVECTION. SEE TROPICAL WAVES DISCUSSION ABOVE FOR MORE DETAILS. OTHERWISE...A BROAD AND STRONG 1031 MB HIGH PRESSURE SYSTEM CENTERED NW OF THE AZORES EXTENDS A SURFACE RIDGE AXIS TO THE WRN ATLC KEEPING FAIR WEATHER CONDITIONS ELSEWHERE ACROSS THE REMAINDER OF THE DISCUSSION AREA. THE FAIR WEATHER IS FURTHER ENHANCED BY A LARGE AREA OF SAHARAN DUST EXTENDING FROM THE WEST AFRICA TO THE ERN AND CENTRAL CARIBBEAN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA