000 AXNT20 KNHC 171757 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUN 17 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC... ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 11N36W TO 02N38W MOVING W AT 10-15 KT. THE WAVE REMAINS WITHIN AN AREA OF MAXIMUM DEEP LAYER MOISTURE AS INDICATED ON TOTAL PRECIPITABLE WATER IMAGERY BETWEEN 32W-42W. CYCLONIC TURNING IN THE MIDDLE TO LOW-LEVEL CLOUD FIELD IS EVIDENT ON SATELLITE IMAGERY IN THE VICINITY OF THE WAVE AXIS WITH SCATTERED MODERATE AND ISOLATED STRONG CONVECTION FROM 03N-09N BETWEEN 35W-42W. TROPICAL WAVE EXTENDS FROM 19N67W THROUGH THE MONA PASSAGE TO INLAND OVER NW VENEZUELA NEAR 10N71W MOVING W AT 10-15 KT. AREAS OF INCREASED LOW TO MID-LAYER MOISTURE ARE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY MOVING ACROSS THE EASTERN AND CENTRAL CARIBBEAN...HOWEVER CONVECTION AT THIS TIME APPEARS TO BE SUPPRESSED DUE TO DRIER AIR FILTERING SOUTHWARD ON THE WESTERN PERIPHERY OF A DRY CYCLONIC CIRCULATION CENTERED NORTH OF THE LESSER ANTILLES NEAR 21N64W. AS THE WAVE TRACKS WESTWARD...IT WILL COME UNDER THE INFLUENCE OF MOIST SOUTHWESTERLY UPPER LEVEL FLOW ACROSS THE CENTRAL CARIBBEAN AND THEREFORE THE POTENTIAL FOR INCREASED CONVECTIVE ACTIVITY. CURRENTLY...ISOLATED SHOWERS ASSOCIATED WITH THE WAVE ARE OCCURRING FROM 16N-20N BETWEEN 65W-72W...INCLUDING PUERTO RICO AND EXTREME EASTERN HISPANIOLA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N13W 06N23W 05N36W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM SOUTH AND 200 NM NORTH OF THE AXIS BETWEEN 19W-35W. A SURFACE TROUGH IS ANALYZED FROM 10N44W TO 03N46W EXHIBITING BROAD CYCLONIC TURNING IN THE LOW TO MIDDLE LEVEL CLOUD FIELD BETWEEN 42W-52W. A LARGE CLUSTER OF SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 02N-09N BETWEEN 42W-53W. ...DISCUSSION... GULF OF MEXICO... WEAK UPPER LEVEL TROUGHING EXTENDS SOUTHWARD ALONG THE EASTERN U.S. SEABOARD AND DIPS ACROSS NE FLORIDA. THIS TROUGHING SUPPORTS A SURFACE TROUGH THAT EXTENDS FROM DAYTONA BEACH TO CLEARWATER FLORIDA. ISOLATED SHOWERS AND TSTMS ARE MOVING OFFSHORE OF THE SE U.S. AND REMAIN N OF 28N BETWEEN 84W-90W. ELSEWHERE...AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER NE MEXICO NEAR 25N102W. THE CIRCULATION EXTENDS UPPER LEVEL RIDGING N-NE INTO THE SOUTHERN U.S. PLAINS AND IS PROVIDING MUCH OF THE GULF WITH OVERALL STABLE NORTHERLY UPPER LEVEL FLOW. HOWEVER...ACROSS THE SW GULF...LOW-LEVEL INSTABILITY ALONG WITH AN UPPER LEVEL DIFFLUENT ENVIRONMENT FROM THE UPPER LEVEL RIDGING IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS SW OF A LINE FROM 25N98W TO THE WESTERN YUCATAN PENINSULA COAST NEAR 20N91W. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF A SURFACE RIDGE EXTENDING FROM THE W ATLC ACROSS THE BAHAMAS AND SOUTH FLORIDA TO A 1020 MB HIGH CENTERED NEAR 27N87W. LIGHT ANTICYCLONIC WINDS ARE IN THE VICINITY OF THE HIGH CENTER WHILE SE WINDS TO 15 KT ARE OCCURRING PRIMARILY W OF 90W. CARIBBEAN SEA... UPPER LEVEL NORTHERLY FLOW IS ACROSS THE NW CARIBBEAN W OF 82W AND CONTINUES TO FILTER INTO THE BASE OF AN UPPER LEVEL TROUGH WITH AN UPPER LEVEL LOW CENTERED NEAR 16N80W. AN UPPER LEVEL TROUGH AXIS EXTENDS NORTHWARD ACROSS EASTERN CUBA AND INTO THE SW NORTH ATLC IN THE VICINITY OF THE CENTRAL BAHAMAS. MODERATELY DRY AIR ALOFT IS ASSOCIATED WITH THIS UPPER LEVEL FEATURE AND IS PROVIDING A LARGE PORTION OF THE WESTERN CARIBBEAN WITH CLEAR SKIES THIS AFTERNOON. FARTHER EAST...A TROPICAL WAVE EXTENDS FROM THE MONA PASSAGE TO LAKE MARACAIBO IN NW VENEZUELA. WHILE LOW-LEVEL CLOUDS EXHIBIT CYCLONIC TURNING...AND AS THE WAVE MOVES BENEATH MOIST SOUTHWESTERLY UPPER LEVEL FLOW IN THE NEXT 24-36 HOURS...INCREASED CONVECTION IS POSSIBLE IN ASSOCIATION WITH THE TROPICAL WAVE OVER THE CENTRAL CARIBBEAN. CURRENTLY ISOLATED SHOWERS AND TSTMS ARE OCCURRING FROM 16N-20N BETWEEN 65W-72W...INCLUDING PUERTO RICO AND EXTREME EASTERN HISPANIOLA. ELSEWHERE...NUMEROUS SHOWERS AND SCATTERED STRONG TSTMS ARE OVER THE SW CARIBBEAN S OF 12N BETWEEN 75W-85W AS A RESULT OF CLOSE PROXIMITY TO THE E PACIFIC ITCZ AXIS ALONG 09N. ATLANTIC OCEAN... WEAK UPPER LEVEL TROUGHING EXTENDS ALONG THE EASTERN U.S. SEABOARD TO NE FLORIDA AND SUPPORTS A SURFACE TROUGH ANALYZED FROM 32N79W TO DAYTONA BEACH FLORIDA. ISOLATED SHOWERS ARE WITHIN 60 NM OF THE TROUGH N OF 30N. OTHER ISOLATED SHOWER AND TSTM ACTIVITY IS INITIATING FARTHER SOUTH OVER THE NW BAHAMAS AND THE SE FLORIDA PENINSULA LARGELY DUE TO AFTERNOON SEABREEZE INTERACTION. THE REMAINDER OF THE W ATLC W OF 65W IS UNDER THE INFLUENCE OF SURFACE RIDGING ALONG 25N EXTENDING INTO THE NE GULF OF MEXICO. THIS SURFACE RIDGING IS LARGELY SUPPORTED ALOFT BY AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 29N63W. FARTHER SE...A SURFACE TROUGH IS ANALYZED FROM 12N-22N ALONG 57W. A 1013 MB LOW IS LOCATED ALONG THE TROUGH AXIS NEAR 16N. ALOFT...THIS FEATURE IS POSITIONED BETWEEN AN UPPER LEVEL HIGH TO THE SOUTH CENTERED NEAR 10N56W AND A RELATIVELY DRY UPPER LEVEL LOW TO THE NORTH CENTERED NEAR 21N64W. AN AREA OF UPPER LEVEL DIFFLUENCE IS MAXIMIZED EAST OF THE SURFACE TROUGH AXIS THAT CONTINUES TO GENERATE SCATTERED MODERATE TO STRONG CONVECTION FROM 14N-21N BETWEEN 52W-58W. ELSEWHERE...AN UPPER LEVEL TROUGH AXIS DIPS INTO THE CENTRAL ATLC FROM NORTH OF THE DISCUSSION AREA ALONG 32N38W TO 28N45W. THIS UPPER LEVEL TROUGHING SUPPORTS A COLD FRONT THAT EXTENDS FROM NORTH OF 32N42W TO 30N46W THEN CONTINUES WESTWARD AS A STATIONARY FRONT ALONG 31N TO BERMUDA NEAR 31N64W. ISOLATED SHOWERS ARE WITHIN 90 NM OF THE ENTIRE FRONT. FINALLY...THE EASTERN ATLC REMAINS UNDER STABLE CONDITIONS N OF 15N E OF 40W DUE TO A SURFACE RIDGE AXIS THAT EXTENDS ALONG 33N30W TO 27N45W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN