000 AXNT20 KNHC 201743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT SEP 20 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1730 UTC. ...TROPICAL WAVES... A TROPICAL WAVE CONTINUES E OF THE CAPE VERDE ISLANDS WITH AXIS EXTENDING FROM 20N21W TO THE MONSOON TROUGH NEAR 13N22W. THE WAVE IS MOVING SLOWLY AT AROUND 5 KT. METEOSAT SAL IMAGERY SHOWS BOTH DUST AND DRY AIR IN THE ENVIRONMENT OF THIS WAVE SUPPRESSING CONVECTION TO THE AREA NEAR THE MONSOON TROUGH MAINLY S OF 16N BETWEEN 18W-24W. A TROPICAL WAVE IS OVER THE CENTRAL TROPICAL ATLANTIC WITH AXIS EXTENDING FROM 21N52W TO 10N53W...MOVING W AT 15 KT. TOTAL PRECIPITABLE WATER IMAGERY SHOWS A MOIST ENVIRONMENT IN THE VICINITY OF THIS WAVE. SCATTERED MODERATE CONVECTION IS FROM 09N- 19N BETWEEN 49W-53W. ELSEWHERE... ISOLATED SHOWERS ARE WITHIN 300 NM OF THE WAVE AXIS. A TROPICAL WAVE IS OVER WESTERN HISPANIOLA WITH AXIS EXTENDING FROM 21N73W TO 12N74W...MOVING W AT 10-15 KT. ALTHOUGH MODERATE DEEP LAYER MOISTURE IS IN THE ENVIRONMENT OF THIS WAVE...NO CONVECTION IS PRESENT DUE TO DEEP LAYER WIND SHEAR. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 15N18W TO 09N39W. THE ITCZ AXIS EXTENDS FROM 09N39W TO 10N49W. OTHER THAN THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...ISOLATED MODERATE CONVECTION IS FROM 08N-13N BETWEEN 26W-31W. ...DISCUSSION... GULF OF MEXICO... AN UPPER-LEVEL TROUGH CONTINUES ACROSS EASTERN US EXTENDING TO THE ATLANTIC AND EASTERN GULF. TO THE WEST...AN UPPER-LEVEL HIGH CONTINUES ACROSS NORTHERN MEXICO AND EXTENDING TO THE WESTERN GULF WATERS. THESE FEATURES ARE KEEPING A DIFFLUENT FLOW ACROSS MOST OF THE BASIN. AT LOW LEVELS...A STATIONARY FRONT REMAINS OVER THE NORTHERN GULF WATERS. A SURFACE TROUGH EXTENDS FROM THE ATLANTIC TO THE GULF NEAR 26N95W. SCATTERED MODERATE CONVECTION REMAINS S OF THE TROUGH BETWEEN 97W-82W. EXPECT IN 24 HOURS FOR A 1012MB SURFACE LOW TO DEVELOP OVER THE W ATLANTIC NEAR 30N80W BRINGING ITS FRONTAL BOUNDARY TO THE EASTERN GULF ENHANCING CONVECTION. CARIBBEAN SEA... UPPER-LEVEL DIFFLUENCE PERSISTS ACROSS THE NORTH-WESTERN HALF OF THE CARIBBEAN AS AN UPPER-LEVEL HIGH CENTERED NEAR 11N77W N OF PANAMA INTERACTS WITH AN UPPER-LEVEL LOW S OF CUBA NEAR 18N82W. DESPITE THIS...FAIR WEATHER PREVAILS ACROSS MOST OF THE BASIN DUE TO DEEP LAYER WIND SHEAR. FOR INFORMATION ABOUT THE TROPICAL WAVE OVER WESTERN HISPANIOLA...REFER TO THE SECTION ABOVE. ABUNDANT MOISTURE IS PRESENT ALONG THE MONSOON TROUGH N OF PANAMA SUPPORTING CLUSTERS OF SCATTERED MODERATE CONVECTION S OF 11N BETWEEN 76W-82W. EXPECT THE SAME WEATHER PATTERN OVER THE NEXT 24 HOURS OVER THE W CARIBBEAN...WHILE ADDITIONAL CONVECTION ADVECTS OVER THE CENTRAL AND EASTERN CARIBBEAN DUE TO THE NEXT TROPICAL WAVE APPROACHING. ...HISPANIOLA... A TROPICAL WAVE IS MOVING ACROSS W HAITI WITH NO SIGNIFICANT CONVECTION ACROSS THE ISLAND. EXPECT CONVECTION TO DEVELOP LATER TODAY AND OVER THE WEEKEND DUE TO OROGRAPHIC LIFTING AND DAYTIME HEATING. ATLANTIC OCEAN... FOR INFORMATION ABOUT THE TROPICAL WAVES...REFER TO THE SECTION ABOVE. AN UPPER-LEVEL HIGH IS CENTERED NEAR 33N42W PAIRED WITH AN UPPER-LEVEL LOW NEAR 24N51W KEEPING A DIFFLUENT FLOW ACROSS THE W ATLANTIC. AT THE SURFACE...A FRONTAL BOUNDARY EXTENDS FROM THE COAST OF LOUISIANA ACROSS THE FLORIDA PENINSULA INTO THE NW ATLANTIC. A SURFACE TROUGH IS PRECEDING THIS FRONTAL BOUNDARY EXTENDING FROM THE E GULF WATERS TO 28N73W. SCATTERED MODERATE CONVECTION IS FROM 26N-36N W OF 68W. A 1021 MB SURFACE HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 29N36W PRODUCING FAIR WEATHER. EXPECT IN 24 HOURS FOR A 1012 MB SURFACE LOW TO DEVELOP OVER THE W ATLANTIC NEAR 30N80W BRINGING ITS FRONTAL BOUNDARY TO THE WESTERN ATLANTIC ENHANCING CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA