000 AXNT20 KNHC 171201 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... FORMER TROPICAL DEPRESSION INGRID DISSIPATED OVER THE MOUNTAINS OF EASTERN MEXICO NEAR 17/0900 UTC. THE REMNANTS OF INGRID WERE LOCATED NEAR LATITUDE 23.7N 99.9W AND WERE MOVING WESTWARD AT 4 NM. MAXIMUM SUSTAINED WINDS DECREASED TO NEAR 20 KT WITH HIGHER GUSTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. HEAVY RAINFALL AND FLOODING STILL POSSIBLE. PLEASE READ THE PUBLIC ADVISORIES ABOUT INGRID THAT ARE ISSUED UNDER WMO HEADER WTNT35 KNHC AND UNDER AWIPS HEADER MIATCPAT5...AND THE FORECAST/ ADVISORIES THAT ARE ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS HEADER MIATCMAT5. CURRENTLY...SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE OVER EASTERN MEXICO FROM 19N- 26N BETWEEN 95W-101W. THE CENTER OF TROPICAL STORM HUMBERTO AT 17/0900 UTC IS NEAR 27.8N 42.7W OR ABOUT 998 NM W-SW OF THE AZORES. ITS PRESENT MOVEMENT IS N-NE AT 4 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 35 KNOTS WITH GUSTS TO 45 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. PRESENTLY...SCATTERED MODERATE CONVECTION AND TSTMS ARE N-NE OF THE LOW CENTER FROM 27N-32N BETWEEN 39W-45W. A BROAD AREA OF LOW PRESSURE IS OVER THE EASTERN YUCATAN PENINSULA ASSOCIATED WITH A SURFACE TROUGH AND A 1007 MB LOW PRESSURE CENTER. THE TROUGH AXIS EXTENDS FROM 21N87W TO THE LOW NEAR 17N88W TO 15N88W. THIS DISTURBANCE IS PRODUCING NUMEROUS STRONG CONVECTION FROM 16N-19N W OF 86W. WIDESPREAD MODERATE/ ISOLATED STRONG CONVECTION IS ELSEWHERE FROM 15N-23N W OF 77W. THIS CONVECTION IS BEING SUPPORTED BY VERY MOIST AIR IN THE REGION AS WELL AS DIFFLUENT FLOW ALOFT FROM AN UPPER-LEVEL TROUGH OVER THE SE GULF AND A WEAK RIDGE THAT EXTENDS FROM THE BAHAMAS TO THE CENTRAL CARIBBEAN SEA. THE LOW IS FORECAST TO MOVE SLOWLY TOWARD THE WEST-NORTHWEST AND EMERGE OVER THE BAY OF CAMPECHE TONIGHT OR WEDNESDAY. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE A LITTLE MORE FAVORABLE FOR DEVELOPMENT DURING THE NEXT DAY OR TWO...AND THE LOW HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. IT IS LIKELY THAT THE LOW IS WILL DRIFT TOWARD THE WEST- NORTHWEST...ACROSS THE SOUTHWESTERN GULF OF MEXICO LATER IN THE WEEK. ENVIRONMENTAL CONDITIONS SHOULD CONTINUE TO BE GENERALLY CONDUCIVE FOR SOME ADDITIONAL DEVELOPMENT DURING THAT TIME. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. ...TROPICAL WAVES... A TROPICAL WAVE IS MOVING ACROSS THE CAPE VERDE ISLANDS. IT AXIS EXTENDS FROM 19N21W TO 09N27W AND IS MOVING W NEAR 5 KNOTS. TOTAL PRECIPITABLE WATER IMAGERY AND METEOSAT SATELLITE IMAGERY SHOW THAT DRY AIR INTRUSION TO THE WAVE ENVIRONMENT OCCURRED WITHIN THE LAST COUPLE OF HOURS. DEEP CONVECTION CONTINUE TO BE SUPPRESSED. SCATTERED MODERATE CONVECTION DEVELOPED WITHIN 170NM NE OF THE WAVE AXIS FROM 16N-20N...CONCURRING WITH A SMALL AREA OF MODERATE TO HIGH MOIST AIR IN THE TOTAL PRECIPITABLE WATER IMAGERY. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL W AFRICA NEAR 12N16W TO 11N24W TO 09N33W. THE ITCZ CONTINUES FROM 09N33W TO 10N46W TO 10N59W. SCATTERED MODERATE CONVECTION IS FROM 07N-10N BETWEEN 23W-32W. SIMILAR CONVECTION WITH ISOLATED TSTMS IS FROM 05N-10N BETWEEN 39W-44W AS WELL AS FROM 10N-13N BETWEEN 44W-62W. ...DISCUSSION... THE GULF OF MEXICO... ADVECTION OF VERY MOIST AIR FROM THE WEST CARIBBEAN SEA CONTINUES TO MOVE ACROSS THE YUCATAN PENINSULA TO THE WESTERN GULF SUPPORTING THE CONVECTION ASSOCIATED WITH THE REMNANTS OF INGRID. MIDDLE-LEVEL DIFFLUENCE OVER THE EASTERN GULF SUPPORTS THIS CONVECTION TOO. SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE INFORMATION ABOUT THE REMNANTS OF INGRID. SCATTERED MODERATE CONVECTION FROM INGRID EXTENDS TO THE WESTERN GULF WATERS S OF 28N W OF 95W. THE BASE OF AN UPPER-LEVEL TROUGH IS OVER THE SE GULF JUST W OF A WEAK RIDGE THAT EXTENDS FROM THE BAHAMAS TO THE CENTRAL CARIBBEAN SEA. THIS SYNOPTIC PATTERN IS GENERATING DIFFLUENT FLOW ALOFT TO SUPPORT SHOWERS AND TSTMS OVER THE YUCATAN CHANNEL AND SE GULF FROM 24N-25N BETWEEN 81W- 85W...INCLUDING KEY WEST. LOW TO MIDDLE LEVEL DRY AIR SUPPORTS FAIR WEATHER ELSEWHERE IN THE BASIN. MOSTLY EASTERLY FLOW OF 15- 20 KT DOMINATES THE BASIN. EVEN THOUGH INGRID DISSIPATED...CONVECTION FROM ITS REMNANTS ARE EXPECTED TO PREVAIL FOR THE REST OF THE DAY TODAY AND POSSIBLY TOMORROW MORNING. A BROAD AREA OF LOW PRESSURE OVER THE FAR NW CARIBBEAN SEA IS STARTING TO MOVE ACROSS THE YUCATAN PENINSULA. THE DISTURBANCE IS EXPECTED TO MOVE TO THE BAY OF CAMPECHE LATER TODAY BRINGING SHOWERS AND THUNDERSTORMS. THIS AREA OF LOW PRESSURE IS EXPECTED TO STALL IN THE BAY OF CAMPECHE FOR SEVERAL DAYS. THE CARIBBEAN SEA... A CUT-OFF LOW EXTENDS A TROUGH ACROSS HISPANIOLA TO THE CENTRAL CARIBBEAN N OF 15N ENHANCING ISOLATED SHOWERS/TSTMS N OF 12N BETWEEN 64W-68W. SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THE MONSOON TROUGH ARE OVER THE SOUTHERN BASIN S OF 12N. HISPANIOLA... A CUT-OFF LOW EXTENDS A TROUGH ACROSS HISPANIOLA TO THE CENTRAL CARIBBEAN N OF 15N ENHANCING ISOLATED SHOWERS/TSTMS IN THE ISLAND ADJACENT WATERS. CONVECTION OVER THE ISLAND AT THIS TIME CONTINUES TO BE HINDERED BY DRY STABLE AIR AT THE LOWER LEVELS. EXPECT AFTERNOON AND EVENING SHOWERS TOMORROW ASSOCIATED WITH SURFACE DAYTIME HEATING. THE ATLANTIC OCEAN... THE MAIN FEATURE IN THE ATLC IS TROPICAL STORM HUMBERTO WHICH INFORMATION IS PROVIDED IN THE SPECIAL FEATURES SECTION. THE BASE OF AN UPPER-LEVEL TROUGH IS OVER THE SE GULF JUST W OF A WEAK RIDGE THAT EXTENDS FROM THE BAHAMAS TO THE CENTRAL CARIBBEAN SEA. THIS SYNOPTIC PATTERN IS GENERATING DIFFLUENT FLOW ALOFT TO SUPPORT SHOWERS AND TSTMS OVER THE BAHAMAS AND ADJACENT WATERS FROM 23N-29N BETWEEN 71W-78W. A SURFACE TROUGH IS OVER THE SW N ATLC FROM 28N66W TO 24N70W GENERATING SCATTERED SHOWERS FROM 26N-29N BETWEEN 65W-70W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR