000 AXNT20 KNHC 081754 CCA TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN SEP 08 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 1715 UTC. ...SPECIAL FEATURES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 18W/19W TO THE SOUTH OF 19N MOVING WESTWARD 10 KNOTS A 1008 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 13N. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 12N TO 15N BETWEEN 20W AND 23W...IN COASTAL MAURITANIA FROM 17N TO 19N...AND FROM THE SOUTHWESTERN CORNER OF SENEGAL TO 14N INCLUDING IN WESTERN GAMBIA. SCATTERED STRONG FROM 10N TO 12N BETWEEN 20W AND 30W. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR FURTHER DEVELOPMENT...AND A TROPICAL DEPRESSION MAY FORM LATER TODAY OR TOMORROW WHILE THE LOW MOVES WEST-NORTHWESTWARD ABOUT 10 KNOTS. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. INTERESTS IN THE CAPE VERDE ISLANDS SHOULD MONITOR THE PROGRESS OF THIS SYSTEM...AND TROPICAL STORM WATCHES OR WARNINGS MAY BE REQUIRED IF A DEPRESSION FORMS. HEAVY RAINFALL AND GUSTY WINDS ARE POSSIBLE IN THE CAPE VERDE ISLANDS BY TONIGHT...EVEN IF A TROPICAL CYCLONE DOES NOT FORM. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 35W/36W TO THE SOUTH OF 21N...MOVING WESTWARD 10 TO 15 KNOTS. A 1010 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 16.5N. CONVECTIVE PRECIPITATION... SCATTERED TO NUMEROUS STRONG FROM 18N TO 20N BETWEEN 36W AND 41W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 15N TO 20N BETWEEN 28W AND 41W. THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS WHILE IT MOVES TO THE WEST-NORTHWEST ABOUT 9 KNOTS. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 86W TO THE SOUTH OF 19N...MOVING WESTWARD 10 TO 15 KNOTS. A MIDDLE LEVEL TO UPPER LEVEL TROUGH CUTS THROUGH SOUTH FLORIDA...TO WESTERN CUBA...TO 20N84W IN THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA...TOWARD WESTERN COASTAL HONDURAS. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 17N TO 20N BETWEEN 81W AND 84W. WIDELY SCATTERED TO SCATTERED MODERATE TO ISOLATED STRONG TO THE NORTHWEST OF THE LINE THAT PASSES THROUGH THE WINDWARD CHANNEL...TO 15N80W...TO NORTHEASTERN COASTAL NICARAGUA/EASTERN COASTAL HONDURAS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SENEGAL NEAR 14N17W TO THE 1008 MB LOW PRESSURE CENTER THAT IS ALONG THE 18W/19W TROPICAL WAVE...TO THE 1010 MB LOW PRESSURE CENTER THAT IS ALONG THE 35W/36W TROPICAL WAVE...TO 12N40W. THE ITCZ CONTINUES FROM 12N40W TO 9N46W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 7N TO 10N BETWEEN 42W AND 50W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 6N TO 10N TO THE EAST OF 42W. ...DISCUSSION... FROM THE WESTERN ATLANTIC OCEAN...ACROSS FLORIDA...INTO THE NORTHERN GULF OF MEXICO...TO SOUTH CENTRAL TEXAS... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 35N65W IN THE ATLANTIC OCEAN...TO 32N74W...TO A CYCLONIC CIRCULATION THAT IS NEAR 29N79W...ACROSS FLORIDA ALONG 28N/29N...TO 29N86W. A SHEAR AXIS CONTINUES FROM 29N86W TO THE UPPER TEXAS GULF COAST...AND A CYCLONIC CIRCULATION CENTER THAT IS NEAR 30N101W TO THE NORTH OF DEL RIO...THAT IS ALONG THE TEXAS/MEXICO BORDER. THE SURFACE PRESSURE GRADIENT FOR THE GULF OF MEXICO THAT IS AWAY FROM THE SOUTHWESTERN CORNER OF THE AREA IS FLAT AND WEAK. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG FROM 23N TO 27N BETWEEN 90W AND 94W. CONVECTIVE PRECIPITATION IN THE ATLANTIC OCEAN...SCATTERED MODERATE TO ISOLATED STRONG IN THE BAHAMAS WITHIN A 60 NM RADIUS OF 26N78W. ISOLATED TO WIDELY SCATTERED MODERATE ELSEWHERE TO THE WEST OF 70W. A STATIONARY FRONT PASSES THROUGH 32N74W TO 31N76W. THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 08/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN...IS 0.13 IN BERMUDA. THE REST OF THE GULF OF MEXICO... A SURFACE TROUGH IS IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...ALONG 23N97W 18N93W. CONVECTIVE PRECIPITATION... SCATTERED MODERATE TO ISOLATED STRONG FROM THE MEXICO COAST TO 23N BETWEEN 92W AND 97W. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... A LOW CLOUD CEILING AND A MIDDLE LEVEL CLOUD CEILING COVER THE ICAO STATION KGBK. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE ACROSS THE AREA. MULTILAYERED CLOUD CEILINGS COVER THE DEEP SOUTH OF TEXAS. RAINSHOWERS WITH THUNDER ARE IN THE EASTERN/COASTAL AREAS MORE THAN BEING INLAND. MULTILAYERED CLOUDS AND RAINSHOWERS WITH THUNDER COVER THE MIDDLE TEXAS GULF COASTAL PLAINS...AND FROM THE MIDDLE TEXAS GULF COAST TOWARD HOUSTON...GALVESTON...AND BEAUMONT-PORT ARTHUR. SCATTERED TO BROKEN LOW CLOUDS ARE IN THE COASTAL AREAS FROM SOUTH CENTRAL LOUISIANA EASTWARD. MULTILAYERED CLOUD CEILINGS COVER THE AREA THAT IS AROUND LAKE PONTCHARTRAIN...INCLUDING NEW ORLEANS. SCATTERED TO BROKEN LOW CLOUDS COVER THE COASTAL AREAS OF MISSISSIPPI AND ALABAMA. HIGH CLOUD CEILINGS ARE REPORTED AT THE TAMPA INTERNATIONAL AIRPORT AND AT THE KEY WEST NAVAL AIR STATION. LOW LEVEL CLOUD CEILINGS COVER THE AREA FROM NAPLES TO PUNTA GORDA. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE IN THE COASTAL SECTIONS OF THE U.S.A. GULF COAST STATES. THE REST OF THE CARIBBEAN SEA... MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE AREA THAT IS TO THE EAST OF 80W. SOME OF THE WIND FLOW THAT IS ON THE WESTERN SIDE OF THE AREA OF ANTICYCLONIC WIND FLOW IS ATTRIBUTABLE TO THE SOUTHWESTERN WIND FLOW THAT IS ON THE EASTERN SIDE OF THE SOUTH FLORIDA-TO-20N84W TROUGH. THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 08/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN...IS 0.40 IN SAN JUAN PUERTO RICO...AND 1.53 IN TEGUCIGALPA. THE MONSOON TROUGH IS ALONG 10N73W IN COLOMBIA...11N80W IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA...BEYOND WESTERN/ NORTHWESTERN NICARAGUA. CONVECTIVE PRECIPITATION...ISOLATED MODERATE TO THE SOUTH OF 15N TO THE WEST OF 79W IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. HISPANIOLA... A SURFACE TROUGH EXTENDS FROM THE 1008 MB LOW PRESSURE CENTER REMNANT OF GABRIELLE THAT IS NEAR 25N68.5W...TO 22N70W AND 18N72W IN SOUTHEASTERN HAITI. CONVECTIVE PRECIPITATION... NUMEROUS STRONG FROM 14N TO 18N BETWEEN 70W AND 74W TO THE SOUTH OF HISPANIOLA. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND WIDELY SCATTERED TO SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION ARE WITHIN 240 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N58W TO 28N60W 20N66W 15N73W. MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS HISPANIOLA. THE GFS FORECAST FOR 700 MB SHOWS THAT AN EAST-TO- WEST ORIENTED RIDGE WILL COVER THE AREA FOR AT LEAST THE FIRST 24 TO 30 HOURS OF THE FORECAST. AN INVERTED TROUGH WILL COVER HISPANIOLA FOR THE REST OF THE TIME PERIOD. THE GFS FORECAST FOR 500 MB AND FOR 250 MB SHOWS THAT A NORTHEAST-TO-SOUTHWEST ORIENTED RIDGE WILL COVER THE AREA FOR THE ENTIRE TIME. THE REST OF THE ATLANTIC OCEAN... A SURFACE TROUGH IS ALONG 30N67W 27N68W...TO THE 1008 MB LOW PRESSURE CENTER REMNANT OF GABRIELLE THAT IS NEAR 25N68.5W...TO 22N70W AND 18N72W IN SOUTHEASTERN HAITI. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 22N TO 25N BETWEEN 65W AND 70W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND WIDELY SCATTERED TO SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION ARE WITHIN 240 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N58W TO 28N60W 20N66W 15N73W. AN UPPER LEVEL RIDGE IS ON TOP OF THE AREA OF THE TROUGH AND LOW CENTER. THE CIRCULATION ASSOCIATED WITH THE LOW IS NOT WELL ORGANIZED...AND THE SHOWER AND THUNDERSTORM ACTIVITY IS DISPLACED TO THE EAST OF THE CENTER. UPPER LEVEL WINDS ARE EXPECTED TO BECOME EVEN LESS CONDUCIVE FOR DEVELOPMENT DURING THE NEXT FEW DAYS WHILE THE LOW MOVES NORTHEASTWARD AND THEN NORTH-NORTHEASTWARD ABOUT 10 KNOTS. THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 28N43W CYCLONIC CIRCULATION CENTER TO 23N47W...TO AN 18N53W CYCLONIC CIRCULATION CENTER TO 11N53W. RAINSHOWERS ARE POSSIBLE FROM 16N TO 20N BETWEEN 51W AND 54W. A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N10W IN THE EASTERN ATLANTIC OCEAN...TO 28N18W TO 22N24W. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT. A SURFACE RIDGE PASSES THROUGH 32N43W TO 28N51W TO 20N60W. SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN TO THE NORTH OF 20N TO THE EAST OF 60W...AND AWAY FROM THE 35W/36W TROPICAL WAVE. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR MORE DETAILS ABOUT 1009 MB LOW CENTER REMNANTS OF GABRIELLE NEAR 25N69W. EXPECT 20 TO 25 KNOT WINDS AND SEA HEIGHTS TO 8 FEET FROM 22N TO 26N BETWEEN 65W AND 69W. A SECOND LOW CENTER IS A 1011 MB CENTER THAT IS NEAR 17N37W. EXPECT NORTHEAST TO EAST 20 TO 25 KNOT WINDS AND SEA HEIGHTS TO 9 FEET FROM 17N TO 25N TO THE EAST OF 40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT