000 AXNT20 KNHC 231758 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED OCT 23 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 FEATURE... THE CENTER OF TROPICAL STORM LORENZO AT 23/1500 UTC IS NEAR 29.5N 49.0W AND IS MOVING EAST AT 5 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KNOTS WITH GUSTS TO 50 KNOTS. PUBLIC ADVISORIES ON LORENZO ARE ISSUED UNDER WMO HEADER WTNT33 KNHC AND UNDER AWIPS HEADER MIATCPAT3. FORECAST/ADVISORIES ON LORENZO ARE ISSUED UNDER WMO HEADER WTNT23 KNHC AND UNDER AWIPS HEADER MIATCMAT3. NUMEROUS STRONG CONVECTION IS FROM 27N-29N BETWEEN 46W-48W. SCATTERED MODERATE CONVECTION IS ELSEWHERE FROM 26N-29N BETWEEN 44W-48W. GALE FORCE WINDS ARE ON THE SW GULF OF MEXICO S OF 21N W OF COLD FRONT FROM 28N83W TO 25N90W TO 18N95W. IN THIS REGION...NW TO N WINDS OF 30-35 KT WITH SEAS RANGING FROM 8-13 FT. N-NE NEAR GALE FORCE WINDS ARE FROM 21N-24N W OF FRONT WITH SEAS RANGING FROM 8- 10 FT. GALE FORCE WINDS ARE FORECAST TO SUBSIDE TONIGHT BUT HIGH OR NEAR GALE FORCE WINDS ARE EXPECTED THROUGH FRIDAY AFTERNOON. ...TROPICAL WAVES... A TROPICAL WAVE IS ON THE EASTERN ATLC WITH AXIS EXTENDING FROM 16N21W TO 05N23W AND MOVING WEST AT APPROXIMATELY 5 KT. SSMI TOTAL PRECIPITABLE WATER IMAGERY INDICATE THE WAVE IS MOSTLY EMBEDDED WITHIN A MODERATE MOIST ENVIRONMENT WHILE A SECTOR OF HIGH MOISTURE LIES SE OF THE AXIS. SCATTERED MODERATE CONVECTION IS FROM 03N-12N BETWEEN 18W-23W...COINCIDING WITH THE AREA OF HIGH MOISTURE. TROPICAL WAVE AXIS EXTENDS FROM 10N55W TO 18N55W AND IS MOVING WEST AT ABOUT 10-15 KT. WATER VAPOR IMAGERY SHOW SUBSIDENCE OF VERY DRY AIR WITHIN THE WAVE ENVIRONMENT WHICH IS HINDERING CONVECTION AT THIS TIME. TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AXIS EXTENDING FROM 08N82W TO 20N82W AND MOVING W NEAR 10 KT. WATER VAPOR IMAGERY SHOW DRY AIR SUBSIDING IN THE NORTHERN SECTOR OF THE WAVE N OF 15N WHICH IS SUPPRESSING CONVECTION IN THE NW CARIBBEAN BASIN. IN THE SOUTHERN BASIN...A MOISTURE MAXIMUM IS OBSERVED IN THE SSMI TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS MOSTLY ASSOCIATED WITH THE MONSOON TROUGH ARE S OF 15N BETWEEN 70W-84W. ...THE ITCZ/THE MONSOON TROUGH... A TROPICAL WAVE IS DISRUPTING THE MONSOON TROUGH IN THE EASTERN ATLC. THE ITCZ EXTENDS WEST OF THE WAVE FROM 08N26W TO 03N34W TO 05N42W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE...SCATTERED MODERATE CONVECTION IS FROM 07N-10N BETWEEN 24W- 32W. SIMILAR CONVECTION IS FROM 0N-09N BETWEEN 33W-43W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM THE UPPER GREAT LAKES TO THE SOUTHERN GULF SUPPORTS A PAIR OF COLD FRONTS. THE FIRST COLD FRONT EXTENDS FROM THE SW N ATLC TO CENTRAL FLORIDA TO 27N82W AND THEN SW IN THE GULF ALONG 25N88W TO 18N94W IN THE BAY OF CAMPECHE. A REINFORCING COLD FRONT EXTENDS FROM EASTERN TALLAHASSEE TO 29N85W 26N92W TO EASTERN MEXICO NEAR 23N97W. GALE FORCE WINDS ARE IN THE SW GULF W OF 92W BETWEEN THE TWO FRONTAL BOUNDARIES. A PRE-FRONTAL SURFACE TROUGH IS IN THE BAY OF CAMPECHE FROM 23N90W TO 18N91W. UPPER-LEVEL DIVERGENCE IN THE BAY OF CAMPECHE IS SUPPORTING A CLUSTER OF MODERATE CONVECTION AND TSTMS S OF 22N BETWEEN 90W-94W. WATER VAPOR IMAGERY SHOW THAT DIVERGENT FLOW ASSOCIATED WITH TROPICAL STORM RAYMOND IN THE EAST PACIFIC IS ADVECTING SOME MOISTURE TO THE CENTRAL-SOUTHERN GULF...WHICH IS SUPPORTING A SWATH OF ISOLATED SHOWERS BETWEEN THE TWO FRONTS AND IN THE SE BASIN. THE REINFORCING COLD FRONT WILL OVERTAKE THE FRONT AHEAD OF IT AND WILL CONTINUE TO DRIFT E-SE TO EXTEND ACROSS SOUTHERN FLORIDA TONIGHT. LATER TODAY THE PORTION OF THE FRONT OVER THE GULF IS EXPECTED TO BECOME STATIONARY. GALE FORCE WINDS ARE FORECAST TO SUBSIDE TONIGHT BUT HIGH WINDS ARE EXPECTED THROUGH FRIDAY AFTERNOON. THE CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AXIS EXTENDING FROM 08N82W TO 20N82W AND MOVING W NEAR 10 KT. WATER VAPOR IMAGERY SHOW DRY AIR SUBSIDING IN THE NORTHERN SECTOR OF THE WAVE N OF 15N WHICH IS SUPPRESSING CONVECTION IN THE NW CARIBBEAN BASIN. IN THE SOUTHERN BASIN...A MOISTURE MAXIMUM IS OBSERVED IN THE SSMI TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS MOSTLY ASSOCIATED WITH THE MONSOON TROUGH ARE S OF 15N BETWEEN 70W-84W. A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE WINDWARD PASSAGE AND SUPPORTS A SURFACE TROUGH FROM THE SOUTHERN BAHAMAS NEAR 22N72W TO 17N75W. ISOLATED SHOWERS AND TSTMS ARE ACROSS SOUTHEASTERN BAHAMAS...THE WINDWARD PASSAGE...EASTERN CUBA AND JAMAICA. A SURFACE TROUGH IS SE OF PUERTO RICO FROM 17N64W TO 13N64W. A CLUSTER OF HEAVY SHOWERS AND TSTMS ASSOCIATED WITH THIS TROUGH HAS DEVELOPED WITHIN THE LAST COUPLE OF HOURS FROM 13N-16N BETWEEN 65W-68W. THE TROPICAL WAVE WILL CONTINUE TO DRIFT WESTWARD AND IS EXPECTED TO MOVE ACROSS CENTRAL AMERICA TONIGHT. THE SURFACE TROUGH IN THE EASTERN BASIN IS FORECAST TO MOVE W AND DISSIPATE LATER TODAY. A NEW TROPICAL WAVE WILL BE MOVING ACROSS THE LESSER ANTILLES FRIDAY NIGHT. HISPANIOLA... A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE WINDWARD PASSAGE AND SUPPORTS A SURFACE TROUGH FROM THE SOUTHERN BAHAMAS NEAR 22N72W TO ADJACENT WATERS SW OF HAITI NEAR 17N75W. ISOLATED SHOWERS AND TSTMS ARE OVER THE WINDWARD PASSAGE. ISOLATED SHOWERS ARE LIKELY ACROSS THE ISLAND AND ADJACENT WATERS THROUGH TONIGHT. THESE SHOWERS WILL CONTINUE TO DISPLACE W-NW AS THE UPPER-LEVEL LOW DRIFTS IN THAT DIRECTION. A DRY AIRMASS IS EXPECTED TO ENTER THE DOMINICAN REPUBLIC BY EARLY THURSDAY WHICH WILL LIKELY HELP TO SUPPRESS CONVECTIVE ACTIVITY. THE ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM THE UPPER GREAT LAKES TO THE SOUTHERN GULF SUPPORTS A COLD FRONT THAT ENTERS THE SW N ATLC NEAR 30N77W TO CAPE CANAVERAL...SW THROUGH CENTRAL FLORIDA AND THE SOUTHERN GULF. ISOLATED SHOWERS AND TSTMS ARE ACROSS THE NORTHERN BAHAMAS. A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE WINDWARD PASSAGE AND SUPPORTS A SURFACE TROUGH FROM THE SOUTHERN BAHAMAS NEAR 22N72W TO ADJACENT WATERS SW OF HAITI NEAR 17N75W. ISOLATED SHOWERS AND TSTMS ARE ACROSS SE BAHAMAS. TROPICAL STORM LORENZO IS IN THE CENTRAL ATLC. SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE INFORMATION. FURTHER EAST...SE OF LORENZO...A 1019 MB HIGH PRESSURE CENTER IS NEAR 26N38W...WHICH IS EXPECTED TO MERGE WITH ANOTHER HIGH PRESSURE CENTER NORTHWARD WITHIN THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR