000 AXNT20 KNHC 011037 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN SEP 01 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 0952 UTC. ...TROPICAL WAVES... A TROPICAL WAVE ASSOCIATED WITH A 1009 MB LOW PRESSURE IS EAST OF THE CAPE VERDE ISLANDS. ITS AXIS EXTENDS FROM 19N20W TO THE LOW NEAR 16N20W TO 11N20W AND IS MOVING W NEAR 5 KT. METEOSAT SAL TRACKING IMAGERY SHOW SOME DRY AIR WITHIN THE WAVE ENVIRONMENT N OF 16N AND E OF ITS AXIS WHICH IS LIMITING CONVECTIVE ACTIVITY. SCATTERED MODERATE CONVECTION IS WEST OF THE LOW CENTER FROM 14N-17N BETWEEN 21W-25W. A TROPICAL WAVE ASSOCIATED WITH A 1009 MB LOW EXTENDS AN AXIS FROM 17N58W TO THE LOW NEAR 14N58W TO 10N58W AND MOVES W NEAR 10 KT. TOTAL PRECIPITABLE WATER IMAGERY DEPICT THE WAVE CONTINUES WITHIN A HIGH MOIST ENVIRONMENT WITH MAXIMUM VALUES NOW EXTENDING EAST AND WEST OF THE WAVE AXIS. SCATTERED MODERATE CONVECTION COINCIDES WITH THE AREAS OF MOISTURE MAXIMA AND IS LOCATED FROM 12N-17N BETWEEN 51W-58W AS WELL AS FROM 14N-17N BETWEEN 58W-65W. A TROPICAL WAVE IS IN THE FAR WESTERN CARIBBEAN SEA WITH AXIS EXTENDING ALONG 22N85W TO 11N86W AND MOVING W NEAR 10 KT. TOTAL PRECIPITABLE WATER IMAGERY SHOW A DECREASE IN MOISTURE WITHIN THE WAVE ENVIRONMENT. THE WAVE IS NOW COUPLED TO A WEAK RIDGE AXIS OVER THE WESTERN BASIN IN THE UPPER LEVELS AND ITS CONVECTION HAS REDUCED TO ISOLATED SHOWERS WITHIN 90 NM EITHER SIDE OF THE AXIS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE WEST AFRICAN COAST NEAR 16N16W TO 10N30W 10N40W 12N51W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES ALREADY DISCUSSED...SCATTERED MODERATE CONVECTION IS FROM 04N-11N E OF 37W AS WELL AS FROM 04N- 15N BETWEEN 40W-50W. ...DISCUSSION... GULF OF MEXICO... DRY AND STABLE AIR ALOFT CONTINUE TO SUPPORT FAIR WEATHER ACROSS MOST OF THE BASIN WHILE SOUTHEASTERLY WIND IN THE RANGE OF 5-10 KT DOMINATES IN THE SURFACE. IN THE SE GULF...AN UPPER LEVEL ELONGATED LOW CENTERED NEAR THE FLORIDA KEYS IS SUPPORTING ISOLATED SHOWERS AND TSTMS FROM 24N-27N E OF 83W. OTHERWISE...A SURFACE TROUGH IS IN THE BAY OF CAMPECHE ALONG 21N92W TO 15N96W. UPPER LEVEL DIFFLUENCE FROM A WEAK RIDGE W OF 95W AND THE LOW CENTERED NEAR THE FLORIDA KEYS IS SUPPORTING SCATTERED MODERATE CONVECTION AND TSTMS IN SOUTHERN MEXICO AND GUATEMALA. THE TROPICAL WAVE IN THE W CARIBBEAN SEA WILL CONTINUE TO MOVE WESTWARD THROUGH THE YUCATAN CHANNEL EARLY TODAY PASSING OVER THE YUCATAN PENINSULA TONIGHT. THE WAVE IS EXPECTED TO WEAKEN OVER THE BAY OF CAMPECHE MON THROUGH WED. A WEAK TROUGH WILL PASS E ACROSS THE N CENTRAL WATERS ON TUE AND THROUGH THE NE WATERS ON WED. CARIBBEAN SEA... A TROPICAL WAVE IS IN THE FAR WESTERN CARIBBEAN SEA WITH AXIS EXTENDING ALONG 22N85W TO 11N86W. TOTAL PRECIPITABLE WATER IMAGERY SHOW A DECREASE IN MOISTURE WITHIN THE WAVE ENVIRONMENT. THE WAVE IS NOW COUPLED TO A WEAK RIDGE AXIS OVER THE WESTERN BASIN IN THE UPPER LEVELS AND ITS CONVECTION HAS REDUCED TO ISOLATED SHOWERS WITHIN 90 NM EITHER SIDE OF THE AXIS. UPPER LEVEL DIFFLUENCE FROM AN ELONGATED LOW CENTERED NEAR THE FLORIDA KEYS AND THE WEAK RIDGE ACROSS THE WESTERN CARIBBEAN IS ENHANCING SCATTERED MODERATE CONVECTION AND TSTMS E OF THE WAVE FROM 15N-23N BETWEEN 74W-83W. SIMILAR CONVECTION IS OCCURRING IN THE SOUTHERN BASIN S OF 13N E OF 78W ASSOCIATED WITH THE MONSOON TROUGH. SHOWERS AND TSTMS CONTINUES IN THE DOMINICAN REPUBLIC E OF 70W BEING SUPPORTED BY AN UPPER LEVEL LOW CENTERED OVER HISPANIOLA. SCATTERED MODERATE CONVECTION AND TSTMS ASSOCIATED WITH A TROPICAL WAVE THAT APPROACHES THE LESSER ANTILLES ARE AFFECTING THE EASTERN BASIN FROM 14N-17N E OF 66W. THE TROPICAL WAVE OVER THE WESTERN CARIBBEAN WILL MOVE ACROSS THE YUCATAN PENINSULA AND CENTRAL AMERICA ON SUN. A SECOND TROPICAL WAVE/LOW WILL PASS THROUGH THE E CARIBBEAN ON SUN AND MON. THE LOW IS EXPECTED TO WEAKEN AS THE WAVE MOVES THROUGH THE CENTRAL CARIBBEAN TUE AND WED. HISPANIOLA... RAINSHOWERS AND TSTMS CONTINUES IN THE DOMINICAN REPUBLIC E OF 70W BEING SUPPORTED BY AN UPPER LEVEL LOW CENTERED OVER THE ISLAND. THE UPPER LOW WILL SHIFT W THROUGH EARLY WED. A TROPICAL WAVE WILL ENTER THE CARIBBEAN SUN AND PASS OVER THE ISLAND TUE AND WED. THEREFORE SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH EARLY THU. ATLANTIC OCEAN... SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE OCCURRING IN THE BAHAMAS AND ADJACENT WATERS FROM 22N-29N W OF 72W. THIS PRECIPITATION ACTIVITY COINCIDES WITH AN AREA OF UPPER LEVEL DIFFLUENCE FROM A LOW CENTERED NEAR THE FLORIDA KEYS AND A RIDGE TO THE E CENTERED NEAR 26N68W. A BROAD UPPER TROUGH IS N OF 30N W OF 30W SUPPORTING A FRONTAL SYSTEM ASSOCIATED WITH A 1015 MB LOW NEAR 33N60W. A COLD FRONT EXTENDS FROM THE LOW INTO THE DISCUSSION AREA ALONG 30N61W TO 28N66W WHERE IT TRANSITIONS TO A DISSIPATING COLD FRONT TO 27N68W. A SURFACE PRE-FRONTAL TROUGH EXTENDS ALONG 29N61W TO 22N63W GENERATING SCATTERED SHOWERS AND TSTMS FROM 21N-24N BETWEEN 62W-66W AS WELL AS WITHIN 60 NM EITHER SIDE OF THE TROUGH AXIS FROM 26N-29N. OTHERWISE...BESIDES THE TROPICAL WAVES ALREADY DISCUSSED...SURFACE RIDGING AND DRY STABLE AIR DOMINATES THE REMAINDER BASIN SUPPORTING FAIR WEATHER. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR