000 AXNT20 KNHC 240535 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU JUL 23 2015 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 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE IN THE TROPICAL ATLC EXTENDS ALONG 37W FROM 9N-17N MOVING W 10-15 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS N OF ANY DEEP MOISTURE. THE NOAA/NESDIS AEROSOL PRODUCT AND THE LAST VISIBLE SATELLITE IMAGERY INDICATES THAT THE WAVE REMAINS EMBEDDED WITHIN A PLUMB OF AEROSOLS OR SAHARAN DUST LIMITING ANY ASSOCIATED CONVECTION. TROPICAL WAVE IN THE CENTRAL CARIBBEAN EXTENDS ALONG 77W/78W S OF 18N TO ACROSS PANAMA MOVING W 20-25 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED WITHIN A BROAD AREA OF MODERATE TO DEEP MOISTURE THAT COVERS THE CARIBBEAN W OF 70W. NO ASSOCIATED DEEP CONVECTION BUT IS ENHANCING THE ACTIVITY ASSOCIATED WITH THE UPPER LOW. TROPICAL WAVE IN THE W CARIBBEAN EXTENDS ALONG 88W S OF 17N TO ACROSS CENTRAL AMERICA MOVING W-SW NEAR 15-20 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED WITHIN A BROAD AREA OF MODERATE TO DEEP MOISTURE THAT COVERS THE CARIBBEAN W OF 70W. NO ASSOCIATED DEEP CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 13N17W ALONG 10N23W TO 8N35W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 8N43W TO SOUTH AMERICA NEAR 6N55W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 250 NM S OF THE MONSOON TROUGH E OF 26W TO THE COAST OF AFRICA AND WITHIN 150 NM N OF THE ITCZ 45W-50W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM S OF THE MONSOON TROUGH/ITCZ BETWEEN 27W-43W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE IS ANCHORED OVER THE FLORIDA PANHANDLE COVERING THE E GULF WHILE THE UPPER LOW CENTERED IN THE SW GULF NEAR 24N93W COVERS THE REMAINDER OF THE GULF. THE UPPER RIDGE IS PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED TO NUMEROUS SHOWERS WITH ISOLATED THUNDERSTORMS ACROSS THE NE GULF N OF 28N E OF 87W. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC THROUGH THE STRAITS OF FLORIDA TO NE TEXAS WITH A 1018 MB HIGH NEAR 26N87W. ISOLATED SHOWERS ARE POSSIBLE ACROSS THE FAR E GULF S OF 28N E OF 85W LEAVING THE REMAINDER OF THE GULF WITH CLEAR SKIES TONIGHT. SURFACE RIDGE WILL PERSIST THROUGH SUN. A TROUGH OF LOW PRESSURE MAY ENTER THE NE GULF SUN NIGHT. CARIBBEAN SEA... AN UPPER LOW IS CENTERED JUST S OF HAITI NEAR 17N75W WITH AN UPPER TROUGH COVERING THE CARIBBEAN BETWEEN 69W-85W. THIS UPPER TROUGH COUPLED WITH THE TROPICAL WAVE IS GENERATING SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS FROM 18N TO OVER HAITI AND E CUBA BETWEEN 72W-77W AND ISOLATED SHOWERS/THUNDERSTORMS DOTTING THE REMAINDER OF THE AREA N OF 18N BETWEEN 77W-86W. AN UPPER RIDGE ANCHORED IN THE TROPICAL ATLC EXTENDS ACROSS THE E CARIBBEAN. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE SW CARIBBEAN S OF 13N W OF 73W TO OVER CENTRAL AMERICA LEAVING THE REMAINDER OF THE CARIBBEAN WITH MOSTLY CLEAR SKIES TONIGHT. W ATLC SURFACE RIDGE WILL MAINTAIN MODERATE TO FRESH TRADE WINDS WITH STRONG TO OCCASIONAL NEAR GALE CONDITIONS OCCURRING OFF THE COAST OF COLOMBIA AND VENEZUELA THROUGH SUN. THE W CARIBBEAN TROPICAL WAVE WILL MOVE OUT THE BASIN OVERNIGHT. THE CENTRAL CARIBBEAN TROPICAL WAVE WILL INTO THE W CARIBBEAN THROUGH SAT. A THIRD TROPICAL WAVE WILL ENTER THE E CARIBBEAN SUN. ...HISPANIOLA... SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS ARE OVER HAITI AND THE GULF OF GONAVE MOVING WESTWARD. THIS ACTIVITY IS DUE TO THE UPPER LOW S OF HAITI AND THE TROPICAL WAVE MOVING AWAY FROM THE ISLAND. THIS UPPER LOW WILL MOVE W GIVING THE ISLAND SOUTHERLY FLOW ALOFT FRI AND SAT WITH AN UPPER RIDGE SETTING UP ON SUN. MOISTURE ASSOCIATED WITH THE TROPICAL WAVE WILL LINGER THROUGH FRI INCREASING THE CHANCES OF AFTERNOON SHOWERS/THUNDERSTORMS. SAT AND SUN WILL SEE A SLIGHT BREAK IN THE MOISTURE AND WITH DAYTIME HEATING COULD STILL PRODUCE A CHANCE OF SHOWERS AND POSSIBLE THUNDERSTORMS DURING THE AFTERNOON/EVENINGS HOURS. ATLANTIC OCEAN... AN E/W ELONGATED UPPER RIDGE IS ANCHORED IN THE W ATLC NEAR 30N68W COVERING THE W ATLC N OF 24N W OF 60W. THE UPPER LOW CENTERED S OF HAITI COVERS THE W ATLC S OF 24N AND IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 23N TO OVER CUBA BETWEEN 74W-76W. AN NE/SW ELONGATED UPPER LOW IS CENTERED IN THE CENTRAL ATLC NEAR 26N50W SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 28N47W TO 30N50W AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 180 NM EITHER SIDE OF THE TROUGH AND FROM 27N-31N BETWEEN 54W-59W. THE ATLC BASIN IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH N OF THE DISCUSSION AREA NEAR 33N35W AND EXTENDING A RIDGE AXIS THROUGH A 1023 MB HIGH NEAR 27N55W THEN W THROUGH THE STRAITS OF FLORIDA AND INTO THE GULF OF MEXICO. SURFACE RIDGE WILL RETREAT EASTWARD AND WEAKEN FRI NIGHT AND SAT AS A WEAK LOW MOVES OFF THE SE U.S. COAST. THE LOW WILL THEN MOVE N OF THE AREA SUN NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW