000 AXNT20 KNHC 020556 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON SEP 02 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0522 UTC. ...SPECIAL FEATURES... A TROPICAL WAVE ASSOCIATED WITH A 1011 MB LOW IS STARTING TO MOVE ACROSS THE LESSER ANTILLES. ITS AXIS EXTENDS ALONG 20N58W TO THE LOW NEAR 14N60W TO 11N61W AND IS MOVING W-NW NEAR 10 KT. UPPER-LEVEL WINDS CONTINUE TO APPEAR CONDUCIVE FOR DEVELOPMENT...HOWEVER TOTAL PRECIPITABLE WATER IMAGERY SHOW MOISTURE HAS DECREASED WITHIN THE WAVE ENVIRONMENT RESULTING IN A DECREASE IN THE RAINSHOWERS AND THUNDERSTORMS ACTIVITY. STRONG DEEP LAYER ENVIRONMENTAL SHEAR IN THE EASTERN CARIBBEAN SEA IS KEEPING MOST OF THE CONVECTION ASSOCIATED WITH THIS SYSTEM E OF THE LOW. SCATTERED MODERATE CONVECTION IS FROM 10N-18N BETWEEN 52W-59W WHILE ISOLATED SHOWERS ARE ELSEWHERE FROM 12N-20N BETWEEN 60W-65W. THERE IS A MEDIUM CHANCE FOR THIS SYSTEM TO BECOME A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... A TROPICAL WAVE ASSOCIATED WITH A 1011 MB LOW IS WEST OF THE CAPE VERDE ISLANDS. THE WAVE HAS BEEN RELOCATED BASED ON SURFACE OBSERVATIONS AND UPPER LEVEL WINDS AND CURRENTLY EXTENDS AN AXIS FROM 20N27W TO THE LOW NEAR 15N28W TO 12N27W MOVING W NEAR 15-20 KT. TOTAL PRECIPITABLE WATER IMAGERY DEPICT MOSTLY A MODERATE MOIST ENVIRONMENT WITHIN 180 NM OF THE LOW PRESSURE CENTER N OF 15N AND A DRIER ENVIRONMENT WITHIN THE SAME DISTANCE S OF 15N. SMALL CLUSTERS OF MODERATE CONVECTION ARE FROM 15N-18N BETWEEN 26W-32W. A TROPICAL WAVE AXIS EXTENDS FROM 18N47W TO 11N49W MOVING W NEAR 10 KT. WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 11N-16N BETWEEN 45W-52W. A TROPICAL WAVE IS ACROSS THE YUCATAN PENINSULA AND GUATEMALA EXTENDING AN AXIS FROM 21N90W TO 12N91W WHICH IS MOVING W NEAR 10 KT. NUMEROUS MODERATE/ISOLATED STRONG CONVECTION AND TSTMS ARE OVER GUATEMALA...WESTERN HONDURAS AND EL SALVADOR BEING SUPPORTED BY UPPER LEVEL DIVERGENCE IN THAT AREA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 18N16W AND CONTINUES ALONG 15N28W TO 09N37W. THE ITCZ BEGINS NEAR 09N38W AND CONTINUES TO 11N48W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES ALREADY DISCUSSED...A CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION IS FROM 06N-11N E OF 17W. SCATTERED MODERATE CONVECTION IS FROM 04N- 10N BETWEEN 18W-47W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY SHOW DRY STABLE AIR ASSOCIATED WITH AN ELONGATED UPPER-LEVEL LOW THAT EXTENDS FROM SE TEXAS TO THE YUCATAN PENINSULA WHICH IS FAVORING FAIR WEATHER W OF 89W. A TROPICAL WAVE IS ACROSS THE YUCATAN PENINSULA AND GUATEMALA EXTENDING AN AXIS FROM 21N90W TO 12N91W. NUMEROUS MODERATE/ISOLATED STRONG CONVECTION AND TSTMS ARE OVER GUATEMALA...WESTERN HONDURAS AND EL SALVADOR BEING SUPPORTED BY UPPER LEVEL DIVERGENCE IN THAT AREA. A MIDDLE-LEVEL TROUGH IS SUPPORTING ISOLATED SHOWERS IN THE NE GULF N OF 28N BETWEEN 85W- 90W. UPPER LEVEL DIFFLUENCE COINCIDING WITH AN AREA OF HIGH MOISTURE IN THE LOWER TO MIDDLE LEVELS OVER THE NW CARIBBEAN SEA IS SUPPORTING SCATTERED MODERATE CONVECTION AND TSTMS THAT EXTENDS TO THE SE GULF S OF 25N E OF 89W. THE N EXTENSION OF THE TROPICAL WAVE WILL MOVE W INTO THE BAY OF CAMPECHE EARLY MON THROUGH EARLY THU. A WEAK TROUGH WILL PASS E ACROSS THE FAR N CENTRAL GULF ON TUE AND THROUGH THE FAR NE GULF ON WED. WEAK SURFACE RIDGE WILL MEANDER FROM CENTRAL FLORIDA TO THE NE TEXAS COAST THROUGH FRI. CARIBBEAN SEA... UPPER LEVEL DIFFLUENCE COINCIDING WITH AN AREA OF HIGH MOISTURE IN THE LOWER TO MIDDLE LEVELS OVER THE NW CARIBBEAN SEA IS SUPPORTING SCATTERED MODERATE CONVECTION AND TSTMS N OF 16N W OF 79W. AN UPPER-LEVEL LOW CENTERED OVER SOUTHERN HAITI IS GENERATING CLOUDINESS AS WELL AS ISOLATED SHOWERS AND TSTMS OVER WESTERN HISPANIOLA AND THE WINDWARD PASSAGE. IN THE SOUTHERN BASIN...THE MONSOON TROUGH IS ENHANCING ISOLATED SHOWERS AND TSTMS S OF 14N W OF 79W AS WELL AS S OF 12N E OF 77W. A TROPICAL WAVE ASSOCIATED WITH A 1011 MB LOW IS STARTING TO MOVE ACROSS THE LESSER ANTILLES. ITS AXIS EXTENDS ALONG 20N58W TO THE LOW NEAR 14N60W TO 11N61W. UPPER-LEVEL WINDS CONTINUE TO APPEAR CONDUCIVE FOR DEVELOPMENT...HOWEVER TOTAL PRECIPITABLE WATER IMAGERY SHOW MOISTURE HAS DECREASED WITHIN THE WAVE ENVIRONMENT RESULTING IN A DECREASE IN THE RAINSHOWERS AND THUNDERSTORMS ACTIVITY. STRONG DEEP LAYER ENVIRONMENTAL SHEAR IN THE EASTERN CARIBBEAN SEA IS KEEPING MOST OF THE CONVECTION ASSOCIATED WITH THIS SYSTEM E OF THE LOW PRESSURE CENTER. SCATTERED MODERATE CONVECTION IS FROM 10N-18N BETWEEN 52W-59W WHILE ISOLATED SHOWERS ARE ELSEWHERE FROM 12N-20N BETWEEN 60W-65W. SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION ABOUT THIS SYSTEM. THE TROPICAL WAVE WILL ENTER THE EASTERN CARIBBEAN TONIGHT REACHING THE CENTRAL CARIBBEAN TUE...AS A POSSIBLE TROPICAL CYCLONE. HISPANIOLA... AN UPPER-LEVEL LOW CENTERED OVER SOUTHERN HAITI IS GENERATING CLOUDINESS AS WELL AS ISOLATED SHOWERS AND TSTMS OVER WESTERN HISPANIOLA AND THE WINDWARD PASSAGE. THE UPPER LOW CURRENTLY OVER HISPANIOLA WILL SHIFT W THROUGH EARLY WED. A TROPICAL WAVE WILL ENTER THE EASTERN CARIBBEAN TONIGHT AND IS EXPECTED TO PASS OVER THE ISLAND TUE THROUGH EARLY THU. THEREFORE SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH AT LEAST EARLY THU. ATLANTIC OCEAN... A BROAD UPPER RIDGE DOMINATES THE W ATLC N OF 23N BETWEEN 61W- 77W. THIS UPPER RIDGE IS PROVIDING DIFFLUENCE ALOFT TO GENERATE ISOLATED SHOWERS AND TSTMS FROM 22N-30N W OF 75W. A 1018 MB HIGH PRESSURE CENTER DEVELOPED AROUND 0300 UTC NEAR 28N74W. FARTHER EAST...AN UPPER-LEVEL TROUGH N OF 30N BETWEEN 58W-65W SUPPORTS A STATIONARY FRONT THAT ENTERS THE REGION NEAR 30N60W TO 27N63W. 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