000 AXNT20 KNHC 261153 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE JUN 26 2012 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 1015 UTC. ...SPECIAL FEATURES... TROPICAL STORM DEBBY IS CENTERED NEAR 28.9N 84.5W AT 26/1200 UTC OR ABOUT 74 NM W OF CEDAR KEY FLORIDA MOVING E AT 03 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 991 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. DOPPLER RADAR AND INFRARED SATELLITE IMAGERY INDICATES SCATTERED SHOWERS AND SCATTERED MODERATE CONVECTION N OF 29N BETWEEN 80W-85W... INCLUDING INLAND NORTHERN FLORIDA AND SOUTHEASTERN GEORGIA. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 04N35W TO 13N32W MOVING W AT 10 KT. A WEAK MONSOONAL 1013 MB LOW IS ALONG THE WAVE AXIS NEAR 08N. THE WAVE REMAINS EMBEDDED WITHIN THIS LOW-LEVEL MONSOON GYRE THAT HAS SET UP ACROSS THE TROPICAL ATLC THE PAST FEW DAYS BETWEEN 28W-40W AND COINCIDES WITH A 700 MB LOW ALOFT CENTERED NEAR 05N34W. ISOLATED MODERATE CONVECTION IS FROM 03N-10N BETWEEN 31W-38W. TROPICAL WAVE EXTENDS FROM 12N63W TO 18N62W MOVING W AT 10-15 KT. EXAMINING TOTAL PRECIPITABLE WATER IMAGERY...THE WAVE AXIS COINCIDES WITH A MAXIMUM OF PRECIPITABLE WATER BETWEEN 60W-64W BRINGING INCREASED LOW TO MIDDLE LEVEL MOISTURE TO THE LESSER ANTILLES AND EASTERN CARIBBEAN THIS MORNING. NO SIGNIFICANT DEEP CONVECTION IS NOTED...HOWEVER ISOLATED SHOWERS ARE OCCURRING WITHIN FROM 11N-18N BETWEEN 60W-66W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO THE 1013 MB MONSOONAL LOW NEAR 08N34W TO 06N40W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N40W TO 04N52W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 05N-11N BETWEEN 11W-19W. ISOLATED MODERATE CONVECTION IS FROM 04N-08N BETWEEN 20W-29W. ...DISCUSSION... GULF OF MEXICO... TROPICAL STORM DEBBY CONTINUES TO IMPACT MUCH OF THE EXTREME NE GULF AND NORTHERN FLORIDA THIS MORNING AS IT DRIFTS EAST SLOWLY. MUCH OF THE STRONG CONVECTION OCCURRING WITH DEBBY IS TO THE NORTHEAST OF CENTER...HOWEVER SURFACE TROUGHING EXTENDS FROM THE SE GULF NEAR 26N85W TO 23N90W AND INTO THE SW GULF NEAR 19N93W WHICH IS PROVIDING FOCUS FOR ISOLATED SHOWERS AND TSTMS FROM 24N-27N BETWEEN 81W-89W. THIS ACTIVITY ALONG WITH CONVECTION ASSOCIATED WITH DEBBY IS LIKELY ENHANCED DUE TO MIDDLE TO UPPER LEVEL DIFFLUENCE ON THE WESTERN AND NORTHERN PERIPHERY OF AN ANTICYCLONIC CIRCULATION CENTERED OVER THE YUCATAN CHANNEL NEAR 21N85W. FARTHER WEST OVER THE REMAINDER OF THE GULF W OF 90W...AN UPPER LEVEL LOW IS CENTERED NEAR 26N94W AND PROVIDES THE NW GULF WITH A FEW UPPER LEVEL CLOUDS...BUT OTHERWISE WATER VAPOR IMAGERY SHOWS DRY AIR AND SUBSIDENCE ALOFT. A WEAK SURFACE RIDGE EXTENDS FROM CENTRAL PORTIONS OF TEXAS ALONG 97W TO A 1013 MB HIGH CENTERED NEAR 20N97W. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE YUCATAN CHANNEL NEAR 21N85W AND PROVIDES NORTHEAST TO EAST WINDS ALOFT TO MUCH OF THE CARIBBEAN W OF 62W. OVERALL THIS MIDDLE TO UPPER LEVEL FLOW IS DRY BUT A FEW PASSING UPPER LEVEL CLOUDS ARE NOTED N OF 16N W OF 72W. TO THE SOUTHEAST OF THE UPPER LEVEL ANTICYCLONE...UPPER LEVEL DIFFLUENCE IS MAXIMIZED OVER PORTIONS OF CENTRAL AMERICA GENERATING SCATTERED SHOWERS AND TSTMS FROM 15N-19N BETWEEN 87W-93W WITH THE MOST INTENSE ACTIVITY THIS MORNING IN THE GULF OF HONDURAS. OTHERWISE...THE REMAINDER OF THE CARIBBEAN IS FAIRLY TRANQUIL WITH ONLY A FEW ISOLATED LOW-TOPPED SHOWERS NOTED ON SATELLITE IMAGERY OCCURRING ACROSS THE FAR EASTERN CARIBBEAN AND LESSER ANTILLES IN ASSOCIATION WITH THE TROPICAL WAVE ALONG 63W MENTIONED ABOVE. ATLANTIC OCEAN... UPPER LEVEL ANTICYCLONIC FLOW COVERS MUCH OF THE SW NORTH ATLC W OF 56W PROVIDING FOR MIDDLE TO UPPER LEVEL OUTFLOW ASSOCIATED WITH TROPICAL STORM DEBBY CENTERED IN THE NORTHEAST GULF OF MEXICO AND MOISTURE ADVECTION EASTWARD BETWEEN 27N AND A COLD FRONT ANALYZED FROM THE CAROLINAS TO CENTRAL MISSISSIPPI. SCATTERED SHOWERS AND ISOLATED TSTMS STRETCH FROM THE NE GULF OF MEXICO INTO THE SW NORTH ATLC OCCURRING N OF 26N W OF 65W. FARTHER EAST OVER THE CENTRAL ATLC...A SURFACE RIDGE HOLDS CONTROL BETWEEN 45W-70W ANCHORED BY A 1022 MB HIGH CENTERED NEAR 35N49W AND A 1021 MB HIGH CENTERED NEAR 27N60W WITH MOSTLY CLEAR SKIES AND FAIR CONDITIONS. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 16N41W THAT EXTENDS A RIDGE AXIS NORTHEASTWARD TO 30N35W. WHILE A WEAK 1020 MB HIGH CENTERED NEAR 30N28W IS PROVIDING OVERALL FAIR CONDITIONS...AN UPPER LEVEL TROUGH TO THE NORTH OF THE DISCUSSION AREA SUPPORTS A COLD FRONT ANALYZED FROM 32N31W SW TO 25N45W. A PRE-FRONTAL SURFACE TROUGH IS SE OF THE COLD FRONT FROM 27N39W TO 23N45W. BOTH BOUNDARIES HAVE ISOLATED SHOWERS OCCURRING WITHIN 120 NM ON EITHER SIDE OF EACH FEATURE. FINALLY...EXAMINING THE SAHARAN AIR LAYER TRACKING PRODUCT BY CIMSS...A LARGE AREA OF SAHARAN DUST COVERS MUCH OF THE EASTERN ATLC FROM FROM 12N TO BEYOND 32N E OF 30W AND FROM 10N-22N BETWEEN 30W-63W. 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