000 AXNT20 KNHC 180004 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE SEP 17 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... THE CENTER OF TROPICAL STORM HUMBERTO AT 17/2100 UTC IS NEAR 30.3N 42.8W OR ABOUT 908 NM WSW OF THE AZORES. HUMBERTO IS MOVING NORTHWARD AT 10 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KNOTS WITH GUSTS TO 50 KNOTS. PLEASE READ THE PUBLIC ADVISORIES ABOUT HUMBERTO THAT ARE ISSUED UNDER WMO HEADER WTNT34 KNHC AND UNDER AWIPS HEADER MIATCPAT4... AND THE FORECAST/ADVISORIES THAT ARE ISSUED UNDER WMO HEADER WTNT24 KNHC AND UNDER AWIPS HEADER MIATCMAT4. ISOLATED MODERATE CONVECTION IS FROM 28N-33N BETWEEN 40W-45W. A 1005 MB LOW IS CENTERED OVER N BELIZE NEAR 18N88W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OVER THE NW CARIBBEAN AND CENTEAL AMERICA FROM EL SALVADOR TO THE N YUCATAN PENINSULA BETWEEN 82W-92W. THIS LOW IS FORECAST TO MOVE SLOWLY TOWARD THE WEST-NORTHWEST AND EMERGE OVER THE BAY OF CAMPECHE ON WEDNESDAY. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE FAVORABLE FOR DEVELOPMENT DURING THE NEXT DAY OR TWO. THIS LOW HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. AND HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. REGARDLESS OF TROPICAL CYCLONE FORMATION...THIS LOW WILL LIKELY SPREAD HEAVY RAINS OVER EASTERN MEXICO. THESE RAINS COULD CAUSE LIFE-THREATENING FLOODS AND MUD SLIDES OVER AREAS ALREADY IMPACTED BY THE TORRENTIAL RAINS ASSOCIATED WITH INGRID AND MANUEL. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE CAPE VERDE ISLANDS FROM 20N24W TO 9N27W MOVING W AT 10 KT. THE SSMI TOTAL PRECIPITABLE WATER VAPOR IMAGERY SHOWS A MOIST AREA ALONG THE WAVE AXIS. AN AREA OF DUST IS NOTED FURTHER W HOWEVER BETWEEN 27W-40W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE WAVE AXIS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SENEGAL NEAR 14N17W TO 15N23W TO 10N32W. THE ITCZ CONTINUES FROM 10N32W TO 10N40W TO 11N50W. SCATTERED MODERATE CONVECTION IS FROM 6N-12N BETWEEN 23W- 29W...AND FROM 7N-11N BETWEEN 40W-44W. ...DISCUSSION... THE GULF OF MEXICO... A WEAK COLD FRONT EXTENDS FROM JACKSONVILLE FLORIDA TO NEW ORLEANS LOUISIANA PRODUCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. CENTRAL AND SOUTH FLORIDA TOGETHER WITH THE SE GULF OF MEXICO HAS ISOLATED MODERATE CONVECTION ADVECTING FROM THE NW CARIBBEAN SEA. FURTHER W... ISOLATED MODERATE CONVECTION IS OVER NE MEXICO...S TEXAS...AND THE W GULF W OF 96W. IN THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W GULF W OF 90W. AN UPPER LEVEL TROUGH IS OVER THE NE GULF SUPPORTING THE SURFACE FRONT. EXPECT OVER THE NEXT 24 HOURS FOR A SURFACE LOW TO ADVECT TO THE BAY OF CAMPECHE WITH CONVECTION. SEE THE SPECIAL FEATURES ABOVE. THE CARIBBEAN SEA... SIGNIFICANT CONVECTION IS OVER THE NW CARIBBEAN AND CENTRAL AMERICA N OF EL SALVADOR. SCATTERED MODERATE CONVECTION IS ALSO OVER CUBA...HISPANIOLA...PUERTO RICO...AND JAMAICA DUE TO EVENING AIRMASS HEATING. A MONSOON TROUGH EXTENDS FROM E PANAMA TO TO N NICARAGUA PRODUCING SCATTERED MODERATE CONVECTION. SILILAR CONVECTION IS OVER NORTHERN COLOMBIA AND NORTHERN VENEZUELA. ELSEWHERE...SCATTERED SHOWERS ARE OVER THE WINDWARD ISLANDS S OF 15N AND E OF 64W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS OVER THE W CARIBBEAN NEAR 17N79W. AN UPPER LEVEL TROUGH IS OVER THE E CARIBBEAN E OF 70W. EXPECT OVER THE NEXT 24 HOURS FOR THE BELIZE SURFACE LOW TO MOVE W...AND LITTLE CHANGE ELSEWHERE. HISPANIOLA... SCATTERED MODERATE CONVECTION IS OVER HISPANIOLA DUE TO AFTERNOON AND EVENING HEATING. AN UPPER LEVEL LOW IS ALSO NE OF THE ISLAND NEAR 22N66W ENHANCING THE CONVECTION. EXPECT MORE CONVECTION TO FORM DURING THE AFTERNOON AND EVENING HOURS TOMORROW. THE ATLANTIC OCEAN... A COLD FRONT IS OVER THE W ATLANTIC FROM 32N70W TO JACKSONVILLE FLORIDA SCATTERED MODERATE CONVECTION IS WITHIN 90 NM OF THE FRONT. SCATTERED MODERATE CONVECTION IS ALSO OVER THE BAHAMAS. A SURFACE TROUGH IS ALSO E OF THE BAHAMAS FROM 28N69W TO 24N72W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 24N-30N BETWEEN 61W-70W. T.S.HUMBERTO IS OVER THE CENTRAL ATLANTIC. SEE ABOVE. OF NOTE IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED NEAR 30N43W NEAR HUMBERTO. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA