000 AXNT20 KNHC 302358 TWDAT TROPICAL WEATHER DISCUSSION NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON SEP 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM JERRY IS CENTERED NEAR 27.3N 44.9W AT 30/2100 UTC OR ABOUT 1078 NM E OF BERMUDA...OR ABOUT 1108 NM WSW OF THE AZORES MOVING E AT 6 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAIN WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. PLEASE SEE LATEST NHC PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 27N-29N BETWEEN 42W-45W. ...TROPICAL WAVES... A TROPICAL WAVE AXIS NEAR THE CAPE VERDE ISLANDS EXTENDS FROM 16N22W TO 4N23W MOVING W AT 20 KT. THE SOUTHERN SECTOR OF THIS WAVE IS EMBEDDED WITHIN THE MONSOON TROUGH WHILE THE NORTHERN SECTOR IS BEING ENGULFED BY SAHARAN DRY AIR. SCATTERED MODERATE CONVECTION IS ON THE WAVE AXIS FROM 8N-10N BETWEEN 23W-26W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS LOCATED W OF THE WAVE AXIS FROM 8N-11N BETWEEN 26W-30W. A TROPICAL WAVE AXIS EXTENDS FROM 21N34W TO 7N37W MOVING W AT 15 KT. THE WAVE REMAINS EMBEDDED WITHIN A VERY MOIST ENVIRONMENT AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. ISOLATED MODERATE CONVECTION IS FROM 6N-20N BETWEEN 32W-39W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE COASTAL AREAS OF MAURITANIA AT 18N16W TO 14N20W. THE ITCZ CONTINUES W OF TWO TROPICAL WAVES AT 9N40W AND CONTINUES TO 7N50W TO THE COAST OF SURINAME AT 6N55W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...ISOLATED MODERATE CONVECTION IS FROM 6N- 12N BETWEEN 40W-50W...AND FROM 7N-11N BETWEEN 54W-60W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A QUASI-STATIONARY FRONT IS JUST INLAND OF THE TEXAS COAST OF FROM 32N95W TO 26N99W. RADAR IMAGERY SHOWS SCATTERED SHOWERS ARE WITHIN 90 NM OF THE FRONT. SURFACE RIDGING REMAINS OVER N FLORIDA AND THE NE GULF OF MEXICO. A SMALL SURFACE TROUGH IS NOTED OVER THE SE GULF OF MEXICO FROM 25N87W TO THE YUCATAN CHANNEL AT 22N85W WITH NO PRECIPITATION. MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF THE GULF. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER THE SE GULF NEAR 26N86W WITH UPPER LEVEL MOISTURE OVER THE N GULF N OF 26N AND STRONG SUBSIDENCE OVER THE S GULF. EXPECT THE TEXAS FRONT TO DISSIPATE OVER THE NEXT 24 HOURS. CARIBBEAN SEA... A SURFACE TROUGH IS OVER THE WESTERN CARIBBEAN SEA S OF THE CAYMAN ISLANDS FROM 19N80W TO 10N81W. GRADUAL DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF DAYS WHILE IT MOVES SLOWLY NORTHWESTWARD. THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. UPPER- LEVEL WINDS ARE EXPECTED TO BE MARGINALLY CONDUCIVE FOR DEVELOPMENT WHEN THE SYSTEM MOVES OVER THE NORTHWESTERN CARIBBEAN SEA AND THE SOUTHERN GULF OF MEXICO LATER THIS WEEK. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. LOCALLY HEAVY RAINFALL WILL CONTINUE OVER PORTIONS OF HAITI...JAMAICA...AND EASTERN CUBA TONIGHT. THESE RAINS WILL SPREAD WESTWARD ACROSS CUBA AND THE CAYMAN ISLANDS ON TUESDAY. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 10N-22N BETWEEN 70W-81W. ELSEWHERE...AFTERNOON AND EVENING AIRMASS THUNDERSTORMS ARE OVER PUERTO RICO. SCATTERED MODERATE CONVECTION IS INLAND OVER CENTRAL AMERICA FROM COSTA RICA TO THE YUCATAN PENINSULA WITH STRONGEST CONVECTION OVER NICARAGUA. A MONSOON TROUGH EXTENDS FROM N COLOMBIA AT 8N75W TO BEYOND COSTA RICA AT 10N85W. SCATTERED MODERATE CONVECTION IS FROM 6N-10N BETWEEN 75W-84W. IN THE UPPER LEVELS...A SMALL UPPER LEVEL TROUGH IS OVER THE NW CARIBBEAN WITH STRONG SUBSIDENCE. A LARGE UPPER LEVEL RIDGE IS OVER THE REMAINDER OF THE CARIBBEAN WITH SIGNIFICANT MOISTURE. EXPECT CONTINUED CONVECTION OVER THE CENTRAL AND SW CARIBBEAN OVER THE NEXT 24 HOURS DUE TO THE SURFACE TROUGH. HISPANIOLA... BANDS OF THUNDERSTORMS ARE NOW OVER HISPANIOLA MOVING FROM S TO N. UPPER LEVEL DIFFLUENCE IS ALSO OVER THE ISLAND. EXPECT SHOWERS AND THUNDERSTORMS TO PERSIST FOR THE NEXT 24 HOURS DUE TO THE SURFACE TROUGH. ATLANTIC OCEAN... A SURFACE TROUGH IS OVER THE W ATLANTIC FROM 31N63W TO W OF THE BAHAMAS AT 24N69W. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM E OF THE TROUGH. TROPICAL STORM JERRY IS OVER THE CENTRAL ATLANTIC. SEE ABOVE. 1019 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 26N56W. ANOTHER 1018 MB HIGH IS OVER THE E ATLANTIC NEAR 25N29W. OF NOTE IN THE UPPER LEVELS...A SMALL UPPER LEVEL LOW IS CENTERED JUST E OF THE LEEWARD ISLANDS NEAR 18N59W. UPPER LEVEL DIFFLUENCE IS E OF THE CENTER CONTRIBUTING TO SOME SCATTERED SHOWERS. ANOTHER UPPER LEVEL LOW IS CENTERED NEAR 16N36W NEAR. AGAIN UPPER LEVEL DIFFLUENCE IS E OF THE CENTER CONTRIBUTING TO SCATTERED SHOWERS. EXPECT OVER THE NEXT 24 HOURS FOR TROPICAL STORM JERRY TO REMAIN CLOSE TO ITS PRESENT LOCATION WITH CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA