000 AXNT20 KNHC 150548 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN SEP 15 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... HURRICANE INGRID IS CENTERED NEAR 22.2N 95.2W AT 15/0600 UTC OR ABOUT 150 NM E OF TAMPICO MEXICO AND ABOUT 175 NM ESE OF LA PESCA MEXICO MOVING NNW AT 6 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 986 MB. MAXIMUM SUSTAINED WIND SPEED IS 75 KT WITH GUSTS TO 90 KT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 19N-24N BETWEEN 92W-96W...WITH WIDELY SCATTERED MODERATE CONVECTION ELSEWHERE FROM 16N-24N BETWEEN 87W- 99W. WHILE INGRID IS FORECAST TO MOVE GENERALLY NORTHWESTWARD THEN WESTWARD THROUGH EARLY MONDAY...ASIDE FROM HURRICANE FORCE WINDS IMPACTING THE SW GULF WATERS AND COASTAL MEXICO...VERY HEAVY RAINFALL IS EXPECTED OVER A LARGE PORTION OF EASTERN MEXICO WHICH IS LIKELY TO RESULT IN FLASH FLOODING AND MUD SLIDES. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT5/WTNT35 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. THE REMNANT 1005 MB LOW OF HUMBERTO IS CENTERED NEAR 26N38W MOVING W AT 10-15 KT AND CONTINUES TO REMAIN ON THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE ANCHORED TO THE NORTHWEST OF THE AZORES. A STRONG PRESSURE GRADIENT IS NOTED ON EARLIER SCATTEROMETER PASSES WITHIN 150 NM OF THE NORTHERN SEMICIRCLE GENERATING GALE FORCE WINDS. IN ADDITION...SCATTERED MODERATE CONVECTION IS FROM 26N-32N BETWEEN 34W-39W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 09N18W TO 19N17W MOVING W AT 10-15 KT. THE WAVE REMAINS GENERALLY EMBEDDED WITHIN THE MONSOON TROUGH HOWEVER GLOBAL MODEL GUIDANCE INDICATES THE WAVE COINCIDES WITH SURFACE TO 700 MB TROUGHING WITH A MID-LEVEL RELATIVE VORTICITY MAXIMUM ALONG THE WAVE AXIS NEAR 14N17W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 12N- 18N BETWEEN 15W-19W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 19N16W TO 10N25W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 10N25W TO 06N30W TO 09N50W. ASIDE FROM CONVECTION ASSOCIATED WITH THE TROPICAL WAVE THAT HAS EMERGED OFF THE AFRICAN COAST... ISOLATED MODERATE CONVECTION IS FROM 07N-10N BETWEEN 25W-32W... FROM 03N-07N BETWEEN 38W-46W...AND FROM 06N-12N BETWEEN 48W-54W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL RIDGE AXIS EXTENDS FROM SOUTHERN MEXICO NEAR 18N95W NORTHWARD OVER THE WESTERN GULF TO A CREST ACROSS THE CENTRAL AND SOUTHERN U.S. PLAINS THIS EVENING. THIS UPPER LEVEL ENVIRONMENT IS PROVIDING MUCH OF THE WESTERN GULF WITH UPPER LEVEL DIFFLUENCE W OF A LINE FROM COASTAL TEXAS NEAR 30N94W TO OVER THE NORTHERN PORTION OF THE YUCATAN PENINSULA NEAR 22N88W. THE MIDDLE TO UPPER LEVEL DIFFLUENCE IS DIRECTLY ENHANCING SCATTERED SHOWERS AND TSTMS ALONG THE SE TEXAS AND MEXICO COAST S OF 27N W OF 94W...WHICH LEADS SOUTHWARD INTO THE SURFACE CIRCULATION OF HURRICANE INGRID CENTERED IN THE SW GULF WATERS. MOISTURE CONTINUES TO ADVECT EASTWARD ACROSS MUCH OF THE SOUTHERN GULF S OF 24N WITH SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING S OF 24N W OF 83W...INCLUDING THE YUCATAN PENINSULA AND CHANNEL THIS EVENING. OTHERWISE...ACROSS THE NORTHERN GULF...WATER VAPOR IMAGERY INDICATES RELATIVELY DRIER AIR IN PLACE N OF 25N E OF 93W DUE PRIMARILY TO NORTHWESTERLY FLOW ALOFT...HOWEVER A DISSIPATING STATIONARY FRONT REMAINS DRAPED ALONG 30N FROM NORTHERN FLORIDA TO NEAR THE MISSISSIPPI RIVER DELTA THAT LACKS ANY SIGNIFICANT PRECIPITATION AND REMAINS DRY. WITH HURRICANE INGRID REMAINING OVER THE SW GULF WATERS THROUGH MONDAY...OUTSIDE OF INGRID'S INFLUENCE...GENERALLY E-SE WINDS WILL PREVAIL ELSEWHERE ACROSS THE GULF IN THE RANGE OF 10-20 KT E OF 90W...AND 15-25 KT W OF 90W. CARIBBEAN SEA... AN UPPER LEVEL LOW IS CENTERED OVER THE NORTH-CENTRAL CARIBBEAN NEAR 16N72W AND IS PROVIDING NORTHWESTERLY TO NORTHERLY FLOW OVER THE WESTERN CARIBBEAN. MUCH OF THIS ANTICYCLONIC FLOW IS ADVECTING MOISTURE FROM THE EAST PACIFIC REGION AND SOUTHERN MEXICO ACROSS THE SW GULF OF MEXICO AND PORTIONS OF CENTRAL AMERICA WHICH IS GENERATING SCATTERED SHOWERS AND TSTMS WEST OF A LINE FROM THE WINDWARD PASSAGE NEAR 19N75W TO 11N84W...THAT INCLUDES PORTIONS OF THE YUCATAN CHANNEL...YUCATAN PENINSULA... AND CUBA. FARTHER SOUTH...ACROSS INLAND PORTIONS OF THE CENTRAL AMERICA...THE MONSOON TROUGH AXIS EXTENDS FROM NORTHERN COLOMBIA TO PANAMA TO HONDURAS AND IS PROVIDING FOCUS FOR ISOLATED SHOWERS AND TSTMS THIS EVENING. AS MENTIONED BEFORE...AN UPPER LEVEL LOW IS CENTERED SOUTH OF HISPANIOLA AND IS GENERATING ELEVATED ISOLATED SHOWERS AND TSTMS FROM 11N-21N BETWEEN 67W- 74W. THE UPPER LEVEL LOW IS FORECAST TO DRIFT NORTHWARD THROUGH MONDAY AND CONTINUE TO PROVIDE THE CENTRAL CARIBBEAN WITH CLOUDINESS AND PRECIPITATION. FINALLY...OVER THE EASTERN CARIBBEAN...UPPER LEVEL SOUTH-SOUTHWESTERLY FLOW DOMINATES AND IS ADVECTING SCATTERED MIDDLE TO HIGH LEVEL CLOUDINESS...HOWEVER BENEATH THIS ENVIRONMENT ALOFT ARE E-SE SURFACE WINDS AND GENERALLY FAIR SKIES WITH ONLY A FEW ISOLATED SHOWERS AND TSTMS E OF 63W. HISPANIOLA... MOST EARLIER CONVECTION CONTINUES TO DIMINISH WITH ONLY ISOLATED SHOWERS REMAINING THIS EVENING. THESE SHOWERS ARE DUE TO LIFTING DYNAMICS ASSOCIATED AN UPPER LEVEL LOW CENTERED SOUTH OF THE ISLAND NEAR 16N72W THAT IS FORECAST TO SLOWLY MOVE NORTHWARD INTO THE SW NORTH ATLC BY MONDAY. AS A RESULT...CONTINUED SHOWER ACTIVITY IS EXPECTED WITH STRONGER CONVECTION ANTICIPATED IN THE AFTERNOON AND EVENING HOURS DURING THE NEXT FEW DAYS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH AXIS IS NOTED ON WATER VAPOR IMAGERY OFFSHORE OF THE CAROLINAS EXTENDING SW TO A BASE OVER NORTHERN FLORIDA AND THE SE GULF OF MEXICO. THIS TROUGH SUPPORTS A COLD FRONT ANALYZED FROM 32N73W TO 30N81W AND ALONG 30N TO THE MISSISSIPPI RIVER DELTA REGION. LOW-LEVEL MOISTURE CONVERGENCE ALONG AND PRIMARILY SOUTH OF THE FRONTAL AREA IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS WESTERN PORTIONS OF THE SW NORTH ATLC REGION W OF 73W...WITH THE STRONGEST ACTIVITY LOCATED ACROSS THE NW AND CENTRAL BAHAMAS. FARTHER EAST...WATER VAPOR IMAGERY INDICATES THE WESTERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS PROVIDING FOR AN OVERALL DIFFLUENT ENVIRONMENT BETWEEN 47W-63W THAT IS SUPPORTIVE OF A WEAK 1012 MB LOW CENTERED NEAR 23N61W. LOW-LEVEL CONVERGENCE ALONG WITH THE UPPER LEVEL DYNAMICS ARE GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS FROM 16N- 32N BETWEEN 52W-63W. FINALLY...ASIDE FROM THE AREA IMPACTED BY THE REMNANT LOW OF HUMBERTO...SURFACE RIDGING CONTROLS THE REMAINDER OF THE CENTRAL AND EASTERN ATLC ANCHORED BY A STRONG 1038 MB HIGH CENTERED NW OF THE AZORES NEAR 42N33W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN