000 AXNT20 KNHC 301804 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE JUL 30 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1725 UTC. ...TROPICAL WAVES... TROPICAL WAVE AXIS EXTENDS FROM 16N35W TO 04N33W MOVING W NEAR 5 KT. IN GENERAL...THE WAVE IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT WITH A SLIGHTLY MOISTER ENVIRONMENT S OF 07N OR THE PORTION OF THE WAVE S OF THE MONSOON TROUGH AXIS. ISOLATED MODERATE CONVECTION IS WITHIN 170 NM EITHER SIDE OF THE WAVE AXIS IN THIS REGION OF THE WAVE. HOWEVER...N OF 07N THERE IS SAL DRY AIR SPARSED IN THE WAVE ENVIRONMENT WHICH IS HINDERING CONVECTION. A SAL OUTBREAK WITH VERY DRY AIR IS JUST BEHIND THIS WAVE. MODEL GUIDANCE INDICATES THAT DRY AIR INTRUSION FROM THIS OUTBREAK MAY ACT TO DISSIPATE THE WAVE BY EARLY THURSDAY. TROPICAL WAVE OR THE REMNANTS OF DORIAN ARE MOVING ACROSS TURKS AND CAICOS AS WELL AS HAITI. ITS AXIS EXTENDS FROM 24N71W TO 14N73W AND IS MOVING W-NW NEAR 5 KT. THE PORTION OF THE WAVE OVER THE W ATLC AND HISPANIOLA IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT WHILE OVER THE CENTRAL CARIBBEAN IT IS EMBEDDED IN DRY AIR. STRONG DEEP LAYER WIND SHEAR HAS ACTED TO DISPLACE MOST OF THE CONVECTION ASSOCIATED WITH THIS WAVE NW OF THE AXIS. THIS CONVECTION IS FROM 21N-26N BETWEEN 67W-70W AND IS DESCRIBED AS SCATTERED MODERATE. SCATTERED RAINSHOWERS WITH ISOLATED TSTMS ARE WITHIN 200 NM W OF THE WAVE AXIS FROM 18N-22N. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE WEST AFRICAN COAST NEAR 13N16W TO 07N26W 06N37W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N37W TO 06N46W 05N52W. BESIDES THE CONVECTION ASSOCIATED WITH THE WAVE ALREADY DISCUSSED...SCATTERED MODERATE CONVECTION IS FROM 06N-10N E OF 17W. A CLUSTER OF MODERATE CONVECTION WITH TSTMS IS FROM 04N-25N BETWEEN 23W-28W. ISOLATED MODERATE CONVECTION IS WITHIN 100 NM N OF THE MONSOON AXIS BETWEEN 20W-23W AND WITHIN 80 NM S OF THE ITCZ AXIS BETWEEN 42W- 47W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...SURFACE RIDGING DOMINATES ACROSS THE GULF WITH RETURN FLOW IN THE RANGE OF 5-10 KT ANCHORED BY A 1022 MB HIGH NEAR 27N87W. MODERATE MOISTURE IS BEING ADVECTED TO THE FLORIDA PENINSULA BY E-SE FLOW OVER THE W ATLC AS WELL AS UPPER LEVEL NORTHEASTERLY FLOW WHICH COMBINED WITH MIDDLE LEVEL DIFFLUENCE IS SUPPORTING SCATTERED SHOWERS AND TSTMS S OF 27N INCLUDING THE FLORIDA STRAITS. A TONGUE OF LOWER AND MIDDLE LEVELS DRY AIR IS SUPPORTING FAIR WEATHER OVER THE REMAINDER BASIN. SURFACE RIDGING IS EXPECTED TO CONTINUE ACROSS MOST OF THE BASIN DURING THE NEXT 48 HOURS AS WELL AS THE CENTER OF HIGH PRESSURE. RAINSHOWERS ACTIVITY IS EXPECTED TO BE LIMITED DURING THIS PERIOD SUPPORTED BY UPPER LEVEL RIDGING AS WELL AS FAIRLY DRY AIR IN THE LOWER TO MIDDLE LEVELS. CARIBBEAN SEA... STRONG TRADEWINDS UP TO 25 KT CONTINUE TO SPREAD OVER THE CENTRAL-SOUTHERN CARIBBEAN WHICH ARE BANKING HIGH LOW LEVEL MOISTURE ALONG THE SOUTHERN COAST OF NICARAGUA...THE COAST OF COSTA RICA AND PANAMA W OF 80W. THE MONSOON TROUGH AXIS IS ENHANCING NUMEROUS MODERATE CONVECTION WITH TSTMS IN THIS REGION S OF 12N. THE REMNANTS OF DORIAN ARE MOVING ACROSS TURKS AND CAICOS AS WELL AS HAITI AND IS GENERATING SCATTERED SHOWERS AND TSTMS OVER CUBA AS WELL AS ISOLATED SHOWERS ACROSS HAITI. OTHERWISE...LOWER AND MIDDLE LEVEL DRY AIR SUPPORTS FAIR WEATHER OVER THE REMAINDER BASIN. THE REMNANTS OF DORIAN ARE EXPECTED TO MOVE ACROSS THE BAHAMAS LATER TODAY GENERATING MORE SHOWERS. HISPANIOLA... MOSTLY DRY AIR IS ACROSS THE HISPANIOLA. ISOLATED SHOWERS ARE OVER HAITI ASSOCIATED WITH THE REMNANTS OF DORIAN. RAINSHOWERS ARE EXPECTED TO REFORM LATER THIS AFTERNOON AS WELL AS WEDNESDAY AFTERNOON/EVENING. ATLANTIC OCEAN... THE REMNANTS OF DORIAN ARE MOVING ACROSS TURKS AND CAICOS AS WELL AS HAITI. STRONG DEEP LAYER WIND SHEAR HAS ACTED TO DISPLACE MOST OF THE CONVECTION ASSOCIATED WITH THIS NOW TRPCL WAVE NW OF ITS AXIS. THIS CONVECTION IS FROM 21N-26N BETWEEN 67W- 70W AND IS DESCRIBED AS SCATTERED MODERATE. SCATTERED RAINSHOWERS WITH ISOLATED TSTMS ARE WITHIN 200 NM W OF THE WAVE AXIS FROM 18N-22N. THE REMNANTS OF DORIAN ARE ALSO GENERATING SCATTERED SHOWERS AND TSTMS OFFSHORE AND ALONG THE NORTHERN COAST OF CUBA WITH ISOLATED SHOWERS ACROSS THE BAHAMAS. AN UPPER LEVEL LOW IS SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 26N45W TO 14N48W WITH ISOLATED SHOWERS WITHIN 130 NM W OF ITS AXIS N OF 21N. A 1024 MB HIGH IS NEAR 30N31W WHICH IS EXPECTED TO DRIFT WESTWARD WITHIN THE NEXT 24 HOURS. BESIDES THE FEATURES ALREADY DISCUSSED...SURFACE RIDGING AND MOSTLY DRY AIR IS SUPPORTING FAIR WEATHER ACROSS THE REMAINING BASIN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR