000 AXNT20 KNHC 171047 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED JUN 17 2015 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 1115 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION BILL IS CENTERED NEAR 31.0N 97.1W AT 17/0900 UTC OR ABOUT 40 NM S OF WACO TEXAS MOVING N AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED MODERATE CONVECTION IS FROM 27N-29N BETWEEN 94W-98W. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/ WTNT32 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. A STRONG PRESSURE GRADIENT EXISTS BETWEEN A 1020 MB HIGH CENTERED NE OF THE BAHAMAS NEAR 28N74W AND LOWER PRESSURE FOCUSED ON A 1006 MB LOW CENTERED ACROSS NORTHERN COLOMBIA NEAR 10N76W THAT IS RESULTING IN NEAR GALE FORCE E-NE WINDS THIS MORNING WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THIS WIND FIELD IS FORECAST TO INCREASE TO GALE FORCE WITHIN 24 HOURS AS THE PRESSURE GRADIENT STRENGTHENS SLIGHTLY. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 09N25W TO 15N22W MOVING W AT 15 KT. THE WAVE HAS EMERGED OFF THE AFRICAN COAST AND COINCIDES WITH 700 MB TROUGHING BETWEEN 21W-27W. NO SIGNIFICANT DEEP CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME. TROPICAL WAVE EXTENDS FROM 04N45W TO 11N44W MOVING W AT 20-25 KT. TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE EMBEDDED WITHIN A RELATIVELY LOW AMPLITUDE AREA OF MOISTURE S OF 09N BETWEEN 43W-50W. NO SIGNIFICANT DEEP CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME. TROPICAL WAVE EXTENDS FROM 04N63W TO 15N60W MOVING W AT 20 KT. THE WAVE COINCIDES WITH WEAK 700 MB TROUGHING BETWEEN 58W-64W ON THE WESTERN EXTENT OF A LENGTHY EASTERLY JET STRETCHING FROM 13N27W TO 10N62W. ISOLATED MODERATE CONVECTION IS MOSTLY INLAND ACROSS PORTIONS OF EASTERN VENEZUELA AND NORTHERN GUYANA. TROPICAL WAVE EXTENDS FROM 08N75N TO 17N73W MOVING W AT 20 KT. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE EMBEDDED WITHIN A POLEWARD SURGE OF DEEP MOISTURE ACROSS THE CENTRAL AND EASTERN CARIBBEAN SEA. NO SIGNIFICANT CONVECTION IS NOTED WITH THE WAVE AT THIS TIME. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 17N16W TO 11N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 11N21W TO 04N45W TO 02N51W. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 27W-41W. ...DISCUSSION... GULF OF MEXICO... THE GULF IS INFLUENCED BY TWO UPPER LEVEL FEATURES...ONE AN ANTICYCLONIC CIRCULATION CENTERED OVER THE WESTERN GULF NEAR 21N94W AND THE OTHER AN UPPER LEVEL LOW CENTERED OVER THE EASTERN GULF NEAR 23N87W. THE ANTICYCLONE IS LARGELY INVOLVED WITH THE UPPER LEVEL DYNAMICS OF TROPICAL DEPRESSION BILL AS IT MOVES FARTHER INLAND ACROSS EASTERN TEXAS THIS MORNING. UPPER LEVEL DIFFLUENCE ALONG WITH CONVERGENT LOW-LEVEL WINDS ACROSS THE NW GULF IS GENERATING SCATTERED TO NUMEROUS SHOWERS AND SCATTERED TSTMS N OF 26N W OF 95W. OTHERWISE...MIDDLE TO UPPER LEVEL CLOUDINESS CONTINUES TO COVER MUCH OF THE BASIN W OF 90W WITH FRESH TO OCCASIONALLY STRONG E-SE BREEZE CONDITIONS PREVAILING THROUGH WEDNESDAY. ELSEWHERE...SURFACE RIDGING CONTINUES TO HOLD ACROSS THE NE GULF ANCHORED BY A 1020 MB HIGH CENTERED NEAR 28N85W. CARIBBEAN SEA... AN UPPER LEVEL LOW CENTERED OVER THE SE GULF OF MEXICO EXTENDS INFLUENCE OVER THE NW CARIBBEAN TO 15N W OF 80W. WEAK LOW-LEVEL SPEED CONVERGENCE ALONG WITH MIDDLE TO UPPER LEVEL DIFFLUENCE IS GENERATING A FEW ISOLATED SHOWERS ACROSS THE NW CARIBBEAN THIS MORNING STRETCHING FROM THE GULF OF HONDURAS TO JAMAICA. THE REMAINDER OF THE BASIN IS UNDER THE INFLUENCE OF GENERALLY WESTERLY FLOW ALOFT A PART OF WHICH...BETWEEN 70W-80W...IS MOSTLY DRY AND STABLE UPON EXAMINING WATER VAPOR IMAGERY. E OF 70W...MIDDLE TO UPPER LEVEL MOISTURE ALONG WITH THE PRESENCE OF A TROPICAL WAVE ALONG 74W IS PROVIDING FOCUS FOR POSSIBLE WIDELY SCATTERED SHOWERS FROM 13N-19N BETWEEN 61W-71W. DUE TO HIGH PRESSURE ANCHORING ITSELF ACROSS THE SW NORTH ATLC REGION... TRADES ARE ANTICIPATED TO REMAIN AT STRONG LEVELS WITH NEAR GALE FORCE...30 KT...FORECAST WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THIS AREA IS FORECAST TO STRENGTHEN FURTHER WITHIN 24 HOURS PRODUCING NEAR GALE TO GALE FORCE CONDITIONS WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. ...HISPANIOLA... CURRENTLY...SKIES REMAIN MOSTLY CLEAR THIS MORNING WITH ISOLATED SHOWERS NOTED ON SATELLITE IMAGERY WITHIN THE SOUTHEASTERN ADJACENT COASTAL WATERS AND MONA PASSAGE REGION. THIS MOISTURE IS LIKELY ASSOCIATED WITH A TROPICAL WAVE PASSING TO THE SOUTH OF THE ISLAND AND ANOTHER TROPICAL WAVE APPROACHING THE WINDWARD ISLANDS ALONG 61W. ATLANTIC OCEAN... A 1020 MB HIGH IS CENTERED OFFSHORE OF THE FLORIDA PENINSULA NEAR 28N74W. FAIR SKIES ARE NOTED ACROSS MUCH OF THE SW NORTH ATLC THIS MORNING. THE ONLY FEATURE ALONG THE DISCUSSION BOUNDARY IS A STATIONARY FRONT ANALYZED FROM 31N43W INTO A 1019 MB LOW CENTERED NEAR 33N53W TO 31N60W TO NE OF BERMUDA NEAR 34N63W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING N OF 27N BETWEEN 55W-72W...AND WITHIN 60 NM EITHER SIDE OF THE FRONTAL BOUNDARY. OTHERWISE...SURFACE HIGH PRESSURE AND RIDGING DOMINATES ELSEWHERE ACROSS THE CENTRAL AND EASTERN ATLC WATERS WITH OVERALL FAIR CONDITIONS PREVAILING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN