Tropical Weather Discussion
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000 AXNT20 KNHC 300541 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED JUL 30 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... A 1012 MB LOW IS CENTERED NEAR 10N41W MOVING W-NW AT 15 KT. THE LOW LIES WITHIN THE MONSOON TROUGH AXIS AND CONTINUES TO SHOW AN IMPRESSIVE SATELLITE PRESENTATION...HOWEVER LACKS ANY ORGANIZED SIGNIFICANT DEEP CONVECTION. ISOLATED MODERATE CONVECTION IS FROM 07N-10N BETWEEN 42W-46W. PLEASE READ THE LATEST NHC TROPICAL WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS MIATWOAT/ABNT20 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 06N23W TO 16N23W MOVING W AT 10-15 KT. A BROAD LOW-LEVEL...850 MB-700 MB...CYCLONIC CIRCULATION IS NOTED IN THE VICINITY OF THE WAVE AND ACROSS AN AREA TO THE WEST OF THE WAVE AXIS ALONG THE MONSOON TROUGH. THIS AREA ALSO COINCIDES WITH A BROAD AREA OF 850 MB RELATIVE VORTICITY FROM 08N-11N BETWEEN 20W-29W. CONVECTION REMAINS LIMITED DUE TO THE SAHARAN AIR LAYER COVERING MUCH OF THE TROPICAL ATLC...HOWEVER ISOLATED MODERATE CONVECTION IS FROM 04N-08N BETWEEN 22W-26W. TROPICAL WAVE EXTENDS FROM 08N44W TO 18N44W MOVING W 15-20 KT. THE WAVE REMAINS TO THE WEST OF A 1012 MB SURFACE LOW CENTERED ALONG THE MONSOON TROUGH NEAR 09N41W. SATELLITE IMAGERY AND GLOBAL MODEL DATA AT 700 MB SEEM TO INDICATE THE WAVE MAY BE LOCATED A FEW DEGREES FARTHER WEST AND THIS IS NOTED ON THE METEOSAT SAHARAN AIR LAYER PRODUCT FROM CIMSS. TROPICAL WAVE EXTENDS FROM 12N98W TO 22N97W MOVING W 15-20 KT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 15N- 19N BETWEEN 97W-100W. ISOLATED MODERATE CONVECTION IS FROM 20N- 22N BETWEEN 97W-99W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W TO 09N23W TO 10N38W TO A 1012 MB LOW PRES NEAR 10N41W TO 07N49W. ISOLATED MODERATE CONVECTION IS FROM 05N-09N BETWEEN 28W-32W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE EASTERN CONUS THAT SUPPORTS A 1012 MB LOW CENTERED IN THE SW NORTH ATLC AND A COLD FRONT ANALYZED FROM THE LOW SW ACROSS THE NORTHERN FLORIDA PENINSULA AND INTO THE GULF NEAR 29N83W. THE COLD FRONT EXTENDS WESTWARD ALONG 29N TO THE TEXAS COAST NEAR GALVESTON BAY. THE FRONT REMAINS FAIRLY PRECIPITATION FREE...HOWEVER A PRE-FRONTAL SURFACE TROUGH ANALYZED TO THE SOUTH OF THE FRONT ALONG 27N IS PROVIDING FOCUS FOR ISOLATED SHOWERS AND TSTMS WITHIN 45 NM EITHER SIDE OF THE SURFACE TROUGH...AND FROM 24N-27N BETWEEN 82W-86W. OTHERWISE...A SURFACE RIDGE ANCHORED BY A 1018 MB HIGH CENTERED NEAR 27N95W PREVAILS ACROSS THE WESTERN GULF AND A NARROW EAST-WEST CORRIDOR FROM THE FLORIDA STRAITS TO THE SW GULF. LOOKING AHEAD...THE FRONTAL BOUNDARY IS FORECAST TO DRIFT SOUTH ACROSS THE EASTERN GULF WATERS THROUGH LATE WEDNESDAY AND GRADUALLY BECOME DIFFUSE ON THURSDAY. MEANWHILE...WEAK RIDGING IS EXPECTED TO REMAIN ACROSS THE WESTERN AND CENTRAL GULF THROUGH FRIDAY. CARIBBEAN SEA... RELATIVELY DRY AND STABLE CONDITIONS ALOFT ARE NOTED OVER MUCH OF THE CARIBBEAN THIS EVENING FOCUSED ON BOTH SIDES OF AN UPPER LEVEL LOW CENTERED OVER THE CENTRAL CARIBBEAN NEAR 16N80W. LINGERING WIDELY SCATTERED AFTERNOON AND EVENING SHOWERS AND TSTMS CONTINUE IN THE VICINITY OF THE WINDWARD PASSAGE. OTHERWISE...THE ONLY OTHER CONVECTION OCCURRING IS SCATTERED SHOWERS AND TSTMS ALONG THE COASTS OF COLOMBIA...PANAMA...AND COSTA RICA BETWEEN 75W-84W...DUE TO THE CLOSE PROXIMITY OF THE MONSOON TROUGH ANALYZED ALONG 07N/08N IN THE EAST PACIFIC REGION. FINALLY...MODERATE TO FRESH TRADES PERSIST WITH SLIGHTLY STRONGER WINDS IN THE RANGE OF 20-25 KT IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. ...HISPANIOLA... CURRENTLY LINGERING ISOLATED SHOWERS AND TSTMS ARE OCCURRING ACROSS WESTERN PORTIONS OF THE ISLAND AND THE ADJACENT COASTAL WINDWARD PASSAGE WATERS. THIS ACTIVITY IS EXPECTED TO CONTINUE DIMINISHING DURING THE NEXT FEW HOURS. OTHERWISE...THE ISLAND REMAINS WITHIN SOUTHWESTERLY FLOW ALOFT AS AN UPPER LEVEL LOW IS CENTERED TO THE SW NEAR 16N80W. GIVEN THE OVERALL DIFFLUENT ENVIRONMENT IN PLACE...SCATTERED SHOWERS AND TSTMS ARE FORECAST WEDNESDAY AFTERNOON INTO THE EVENING WITH PEAK DAYTIME HEATING AND INSTABILITY. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS OVER THE EASTERN CONUS THAT SUPPORTS A 1012 MB LOW CENTERED OFF THE SE U.S. COAST NEAR 32N77W. A COLD FRONT EXTENDS SW FROM THE LOW CENTER TO THE NORTHERN FLORIDA PENINSULA NEAR 29N81W. TO THE SE OF THE FRONT...A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 31N75W TO 28N81W AND INTO THE GULF OF MEXICO. ISOLATED SHOWERS AND TSTMS ARE OCCURRING FROM 25N-31N BETWEEN 75W-80W. FARTHER EAST...AN UPPER LEVEL LOW IS CENTERED NEAR 25N66W WITH MID-LEVEL ENERGY FOCUSED NEARLY IN THE SAME LOCATION THAT SUPPORTS AN AREA OF ISOLATED SHOWERS AND TSTMS FROM 23N-28N BETWEEN 62W-67W. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED NEAR 36N54W. THE RIDGE AXIS EXTENDS SE FROM THE HIGH TO 30N50W TO 20N22W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN

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