000 AXNT20 KNHC 220003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON JUL 21 2014 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 2345 UTC. ...SPECIAL FEATURES... FORMER LOW PRESSURE CENTER EMBEDDED IN THE MONSOON TROUGH AND ASSOCIATED WITH A TROPICAL WAVE HAS INTENSIFIED TO A TROPICAL DEPRESSION NEAR 2000 UTC. AS OF 2100 UTC...TROPICAL DEPRESSION TWO IS LOCATED NEAR 11.6N 43.8W OR ABOUT 1045 NM E OF THE LESSER ANTILLES. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1012 MB. MAXIMUM SUSTAINED WINDS ARE 30 KT WITH GUSTS TO 40 KT. A CLUSTER OF MODERATE CONVECTION IS FROM 10N-12N BETWEEN 43W-46W. RAINBANDS ASSOCIATED WITH THE SYSTEM EXTENDS FROM 9N-14N BETWEEN 42W-46W. SEE THE LATEST NHC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS OVER THE CENTRAL ATLC WITH AXIS EXTENDING FROM 19N35W TO 12N35W MOVING W AT 20 KT. THE WAVE IS SLIGHTLY N OF THE MONSOON TROUGH AND EMBEDDED IN THE DRY SAHARAN AIR LAYER WHICH IS HINDERING CONVECTION. TROPICAL WAVE HAS DETACHED FROM THE CURRENT TROPICAL DEPRESSION TWO. THE WAVE CONTINUES TO MOVE WESTWARD WITH AXIS EXTENDING FROM 18N44W TO 12N45W AT A SPEED OF 20 KT DURING THE PAST 24 HOURS. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL DEPRESSION SE OF THE AXIS...NO OTHER CONVECTIVE ACTIVITY IS ASSOCIATED WITH THE WAVE AS IT IS EMBEDDED IN THE DRY SAHARAN AIR LAYER. TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN WITH AXIS EXTENDING FROM 18N76W TO 10N76W MOVING W AT 20-25 KT DURING THE LAST 24 HOURS. DRY AIR SUBSIDENCE FROM ALOFT AS WELL AS A STRONG DEEP LAYER ENVIRONMENTAL SHEAR OVER THE CENTRAL AND EASTERN CARIBBEAN ARE FACTORS INHIBITING CONVECTION AT THE TIME. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N16W TO 9N21W 12N35W TO A 1013 MB LOW NEAR 11N43W TO 8N45W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 8N45W TO 8N52W TO 7N58W. ASIDE FROM CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-10N BETWEEN W OF 36W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL LOW IS CENTERED JUST N OF FLORIDA AND SUPPORTS A STATIONARY FRONT EXTENDING ACROSS THE SE CONUS AND ALONG THE LOUISIANA GULF COAST. A PRE-FRONTAL SURFACE TROUGH IS ANALYZED FROM THE WESTERN FLORIDA PANHANDLE NEAR 31N85W SW TO 29N87W TO 27N89W. LOW-LEVEL MOISTURE CONVERGENCE IN THE E-SE GULF IS ENHANCING SCATTERED SHOWERS AND TSTMS N OF 23N E OF 89W AS WELL AS THE FLORIDA STRAITS. OTHERWISE...SURFACE RIDGING DOMINATES ELSEWHERE IN THE GULF WHERE VARIABLE WINDS RANGE FROM 5-15 KT. OVER THE WESTERN GULF...DRY AIR SUBSIDENCE FROM THE MID- UPPER LEVELS SUPPORT FAIR WEATHER. EXCEPT FOR A TROPICAL WAVE POSSIBLY EXTENDING TO THE BAY OF CAMPECHE ON TUE MORNING...SURFACE RIDGING AND HIGH PRESSURE IS FORECAST TO PREVAIL THE NEXT TWO TO THREE DAYS. CARIBBEAN SEA... UPPER LEVEL NORTH-NORTHEASTERLY FLOW IS OVER MUCH OF THE WESTERN CARIBBEAN W OF AN UPPER LEVEL LOW CENTERED NEAR 18N75W WITH TROUGH AXIS EXTENDING SOUTHWARD TO A BASE OVER THE SW CARIBBEAN NEAR 11N77W. THIS WIND PATTERN ALOFT IS GENERATING DIFFLUENCE ALONG CUBA WHICH ALONG LOW-LEVEL MOISTURE CONVERGENCE SUPPORT HEAVY SHOWERS AND TSTMS ACROSS THIS ISLAND AND ADJACENT WATERS. THE AXIS OF A TROPICAL WAVE IS JUST SOUTH OF EASTERN CUBA MOVING ACROSS JAMAICA AND COLOMBIA COASTAL WATERS. THERE IS NO CONVECTION ASSOCIATED WITH THE WAVE AT THE TIME. SEE TROPICAL WAVES SECTION FOR MORE DETAILS. ALOFT AND EAST OF THE WAVE AXIS...THE SW PERIPHERY OF AN UPPER-LEVEL ANTICYCLONE CENTERED OVER THE CENTRAL ATLC NEAR 24N48W IS GENERATING A DIFFLUENT ENVIRONMENT ACROSS PORTIONS OF THE EASTERN CARIBBEAN. THIS ENVIRONMENT ALOFT IS SUPPORTING ISOLATED SHOWERS AND TSTMS ACROSS HISPANIOLA. ISOLATED SHOWERS ARE POSSIBLE FOR THE MONA PASSAGE AND WESTERN PUERTO RICO. SCATTERED MODERATE CONVECTION IS OVER INLAND AND COASTAL WATERS OF COSTA RICA AND PANAMA BEING ASSOCIATED WITH THE MONSOON TROUGH. ELSEWHERE...FAIR WEATHER DOMINATES BEING SUPPORTED BY DEEP LAYER DRY AIR. MODERATE TO FRESH TRADES CONTINUE AND ARE EXPECTED TO PERSIST THROUGH MUCH OF THE WEEK AHEAD... OCCASIONALLY WITH STRONGER WINDS 25 TO 30 KT OCCURRING WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA AND NW VENEZUELA. ...HISPANIOLA... AN UPPER LEVEL LOW CENTERED NEAR 18N75W WITH TROUGH AXIS EXTENDING SOUTHWARD TO A BASE OVER THE SW CARIBBEAN ALONG WITH WIND FLOW ASSOCIATED WITH THE SW PERIPHERY OF AN UPPER-LEVEL ANTICYCLONE CENTERED OVER THE CENTRAL ATLC GENERATE A DIFFLUENT ENVIRONMENT ALOFT ACROSS PORTIONS OF THE CENTRAL-EASTERN CARIBBEAN. THIS ENVIRONMENT ALOFT IS SUPPORTING ISOLATED SHOWERS AND TSTMS ACROSS HISPANIOLA AND COASTAL WATERS. WEATHER CONDITIONS ARE EXPECTED TO IMPROVE TUE MORNING. ATLANTIC OCEAN... NORTH-NORTHEASTERLY FLOW ASSOCIATED WITH A WEAK MID-UPPER LEVEL ANTICYCLONE OVER PORTIONS OF THE SW N ATLC AND THE WIND FLOW OF AN IMMEDIATE MID-UPPER LEVEL LOW IS GENERATING A DIFFLUENT ENVIRONMENT IN THIS REGION OF THE ATLC. THIS ALONG WITH LOW- LEVEL MOISTURE CONVERGENCE IS SUPPORTING SCATTERED SHOWERS AND TSTMS N OF 23N W OF 75W. SIMILAR CONVECTION IS ALONG COASTAL WATERS OF NORTHERN HISPANIOLA. SEE SECTION ABOVE FOR MORE DETAILS. THE UPPER LEVEL LOW ALSO SUPPORTS A SURFACE TROUGH ANALYZED FROM 31N58W TO 24N62W. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC ARE UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NEAR 32N39W AND A 1025 MB HIGH CENTERED NEAR 33N33W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR