000 AXNT20 KNHC 131106 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU AUG 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 28W/29W...FROM 18N SOUTHWARD...MOVING WESTWARD 15 KNOTS. THE POSITION OF THE WAVE AT 13/0600 UTC IS SLIGHTLY TO THE EAST OF THE POSITION FOR 13/0000 UTC...BASED ON SATELLITE IMAGERY...700 MB MODEL DATA... AND TPW DATA. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 50W/51W FROM 15N SOUTHWARD MOVING WESTWARD 10 KNOTS. THE POSITION OF THE WAVE AT 13/0600 UTC IS SLIGHTLY TO THE EAST OF THE POSITION FOR 13/0000 UTC...BASED ON SATELLITE IMAGERY...700 MB MODEL DATA...AND TPW DATA. CONVECTIVE PRECIPITATION...ISOLATED MODERATE TO LOCALLY STRONG WITHIN 60 NM ON EITHER SIDE OF 12N51W 10N54W 07N58W. FROM 10N TO 12N BETWEEN 50W AND 52W. A CARIBBEAN SEA TROPICAL WAVE IS ALONG 78W/79W FROM JUST TO THE WEST OF THE WESTERN COAST OF JAMAICA TO PANAMA...MOVING WESTWARD 15 TO 20 KNOTS. THE WAVE COINCIDES WITH A 700 MB TROUGH. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY. THIS WAVE IS MOVING THROUGH AN AREA OF LARGE- SCALE CYCLONIC WIND FLOW THAT SPANS THE CARIBBEAN SEA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL BORDER SECTIONS OF SENEGAL AND GAMBIA NEAR 13N16W...TO 11N24W AND 09N31W. THE ITCZ CONTINUES FROM 09N31W TO 07N44W AND 06N50W. CONVECTIVE PRECIPITATION...ISOLATED MODERATE TO LOCALLY STRONG WITHIN 150 NM ON EITHER SIDE OF 12N16W 09N20W 07N25W 07N37W 08N45W 07N51W. ...DISCUSSION... ...THE GULF OF MEXICO... LARGE-SCALE ANTICYCLONIC WIND FLOW IS SWEEPING ACROSS THE NORTHERN HALF OF THE GULF OF MEXICO...FROM 24N NORTHWARD. A COLD FRONT PASSES THROUGH 32N76W TO A 1013 MB SOUTHERN GEORGIA LOW PRESSURE CENTER. A STATIONARY FRONT CONTINUES FROM THE GEORGIA LOW PRESSURE CENTER...ALONG 30N...BEYOND SOUTHWESTERN LOUISIANA. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG IS ALONG THE UPPER TEXAS GULF COAST. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED MODERATE CONVECTIVE PRECIPITATION ELSEWHERE COVER THE AREA THAT IS FROM 25N TO 31N BETWEEN FLORIDA AND TEXAS. WARMING CLOUD TOP TEMPERATURES AND WEAKENING PRECIPITATION ARE IN THE SOUTHWESTERN CORNER OF THE AREA FROM 22N SOUTHWARD. A SURFACE RIDGE PASSES ACROSS ANDROS ISLAND...INTO THE SOUTH CENTRAL GULF OF MEXICO...TO THE MEXICO GULF COAST NEAR 22N98W. ...THE CARIBBEAN SEA AND HISPANIOLA... ONE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 19N77W BETWEEN SOUTHEASTERN CUBA AND JAMAICA. A SECOND AND COMPARATIVELY WEAKER MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS TO THE SOUTH OF HAITI NEAR 17N72W. THESE TWO INDIVIDUAL CYCLONIC CIRCULATION CENTERS ARE EMBEDDED IN THE OVERALL LARGER-SCALE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC WIND FLOW THAT SPANS THE CARIBBEAN SEA. A SURFACE TROUGH IS ALONG 70W/71W FROM 13N TO 17N. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG ABOUT 60 NM TO THE SOUTH OF THE SOUTHWESTERN PART OF THE COAST OF THE DOMINICAN REPUBLIC. ISOLATED MODERATE FROM 14N TO PUERTO RICO AND HISPANIOLA FROM 65W WESTWARD...AND FROM 11N TO 14N BETWEEN 80W AND CENTRAL AMERICA. RAINSHOWERS ARE POSSIBLE IN GENERAL ELSEWHERE TO THE NORTHWEST AND NORTH OF THE LINE THAT RUNS FROM 18N65W TO 11N68W TO 13N74W TO 09N80W. SURFACE OBSERVATIONS FOR THE DOMINICAN REPUBLIC...SCATTERED LOW LEVEL CLOUDS ARE BEING OBSERVED IN SANTO DOMINGO. FEW LOW LEVEL CLOUDS ARE IN PUNTA CANA. A LOW LEVEL CLOUD CEILING IS BEING REPORTED IN SANTIAGO. THE GFS MODEL FORECAST FOR 250 MB SHOWS THAT THE CURRENT 17N72W CYCLONIC CIRCULATION CENTER WILL MOVE NORTHWESTWARD TO 20N81W. SOUTHERLY WIND FLOW WILL COVER HISPANIOLA FOR MOST OF THE FIRST 24 HOURS OF THE 48-HOUR FORECAST PERIOD THAT STARTS ON 13/0000 UTC. THE CYCLONIC CIRCULATION CENTER EVENTUALLY WILL MOVE TO 20N81W...AND THEN IT WILL DISSIPATE BY THE END OF THE 48-HOUR FORECAST PERIOD. THE GFS MODEL FORECAST FOR 500 MB SHOWS THAT INVERTED TROUGHS WILL MOVE ACROSS HISPANIOLA FOR THE FIRST 24 HOURS OF THE 48-HOUR FORECAST PERIOD. SOUTHEASTERLY WIND FLOW EVENTUALLY COVERS THE ENTIRE AREA FOR DAY TWO. THE GFS MODEL FORECAST FOR 700 MB SHOWS THAT INVERTED TROUGHS WILL MOVE WESTWARD ACROSS HISPANIOLA FOR THE NEXT 48 HOURS. EXPECT VARIATIONS IN THE WIND DIRECTION. THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS IN THE COASTAL WATERS OF THE SOUTH CAROLINA...GEORGIA...AND FLORIDA FROM 29N NORTHWARD. COMPARATIVELY DRIER AIR IN SUBSIDENCE IS TO THE NORTH AND NORTHWEST OF 29N81W BEYOND 32N78W. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N76W TO A 1013 MB SOUTHERN GEORGIA LOW PRESSURE CENTER. A STATIONARY FRONT CONTINUES FROM THE GEORGIA LOW PRESSURE CENTER...ALONG 30N...BEYOND SOUTHWESTERN LOUISIANA. CONVECTIVE PRECIPITATION IN THE ATLANTIC OCEAN... WIDELY SCATTERED TO SCATTERED MODERATE AND ISOLATED STRONG FROM THE WATERS THAT ARE BETWEEN ANDROS ISLAND AND SOUTHEASTERN FLORIDA...TO 28N78W...AND TO THE NORTHWEST OF 32N68W 29N72W 27N80W. A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 25N52W CYCLONIC CIRCULATION CENTER...TO A 23N64W CYCLONIC CIRCULATION CENTER. THE SURFACE TROUGH THAT WAS ALONG 31N31W 26N39W 29N47W FOR THE 13/0000 UTC MAP ANALYSIS WEAKENED AND DISSIPATED. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE FROM 23N NORTHWARD BETWEEN 47W AND 66W. AN UPPER LEVEL TROUGH EXTENDS FROM A 31N24W CYCLONIC CIRCULATION CENTER...TO 24N26W. COMPARATIVELY DRIER AIR IN SUBSIDENCE SURROUNDS THE CYCLONIC CENTER AND TROUGH. A SURFACE RIDGE PASSES THROUGH 32N58W TO 28N63W...TO ANDROS ISLAND IN THE BAHAMAS...INTO THE SOUTH CENTRAL GULF OF MEXICO...TO THE MEXICO GULF COAST NEAR 22N98W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT