000 AXNT20 KNHC 301200 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU JUN 30 2011 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 FEATURE... T.S. ARLENE IS CENTERED NEAR 21.6N 97.5W AT 30/1200 UTC CURRENTLY MAKING LANDFALL NEAR CABO ROJO MEXICO MOVING W AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 993 MB. MAXIMUM SUSTAINED WIND SPEED IS 56 KT. PLEASE SEE THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. NUMEROUS MODERATE CONVECTION IS WITHIN 175 NM FROM THE CENTER OF THE STORM IN ALL DIRECTIONS. SCATTERED STRONG CONVECTION IS EMBEDDED WITHIN THIS AREA OF MODERATE CONVECTION ACROSS THE NRN HEMISPHERE WITH ISOLATED STRONG CONVECTION ALONG THE SRN HEMISPHERE. NUMEROUS MODERATE CONVECTION IS ALSO SE OF THE CENTER FROM 14N-19N BETWEEN 88W-97W WITH A CLUSTER OF STRONG CONVECTION FROM 14N-17N BETWEEN 94W-97W. ...TROPICAL WAVES... A TROPICAL WAVE IS IN THE WRN TROPICAL ATLC ALONG 54/55W FROM 7N-15N MOVING W 15-20 KT. THE WAVE REMAINS IN AN AREA OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. BROAD CYCLONIC SURFACE FLOW IS ABOUT THE WAVE AXIS. SCATTERED MODERATE/STRONG CONVECTION FROM 10N-14N BETWEEN 52W-58W. A TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN S OF ERN CUBA ALONG 75W/76W FROM 14N-20N MOVING W NEAR 10 KT. THE WAVE IS E OF AN AREA OF MODERATE MOISTURE VALUES THAT HAVE MOVED ACROSS THE WRN CARIBBEAN. THIS WAVE LOST MOST OF ITS ENERGY AFTER INTERACTING WITH AN UPPER LEVEL LOW NOW DIRECTLY OVER THE WAVE. THE UPPER LEVEL LOW IS DRAWING DRY AIR ALOFT INTO THE CENTRAL CARIBBEAN WHICH IS INHIBITING DEEP CONVECTION NEAR THE WAVE AXIS. A SMALL AREA OF SHOWERS/THUNDERSTORMS IS E OF JAMAICA FROM 18N-19N BETWEEN 75W-77W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 24N ALONG 20N7W 19N15W 13N18W 9N27W. THE ITCZ CONTINUES FROM 9N27W ALONG 8N36W 7N43W 6N53W. ISOLATED MODERATE/STRONG CONVECTION IS ALONG A SWATH FROM THE AFRICAN COAST TO 47W FROM 6N-10N. ...DISCUSSION... GULF OF MEXICO... TROPICAL STORM ARLENE CONTINUES TO IMPACT MUCH OF THE SW GULF OF MEXICO. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. HIGH LEVELS OF MOISTURE ARE ACROSS THE MAJORITY OF THE BASIN. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE OVER THE SE GULF FROM 22N-26N BETWEEN 81W089W. ALOFT... ANTI-CYCLONIC OUTFLOW FROM ARLENE IS COVERING MUCH OF THE WRN GULF. AN UPPER RIDGE AXIS ALSO EXTENDS FROM SRN LOUISIANA ACROSS CENTRAL FLORIDA AND INTO THE WRN ATLC. AN UPPER LEVEL TROUGH IS SINKING SWD OVER THE ERN CONUS AND IS JUST N OF THE NE GULF. THIS UPPER TROUGH SUPPORTS A SURFACE TROUGH EXTENDING ACROSS THE FLORIDA PANHANDLE TO 30N86W. A FEW SCATTERED SHOWERS/THUNDERSTORMS ARE S OF THE TROUGH ALONG A LINE FROM 29N83W TO 30N88W. A WEAK SURFACE RIDGE IS OVER THE N CENTRAL GULF AROUND A 1015 MB HIGH NEAR 30N88W. MODERATE DRY AIR ALOFT IS OVER THE SURFACE RIDGE. THIS COMBINATION IS PROVIDING MOSTLY FAIR CONDITIONS OVER THE NRN GULF N OF 28N W OF 84W...BESIDES THE LINE OF SHOWERS IN THE NE GULF MENTIONED PREVIOUSLY. EVEN THOUGH ARLENE WILL BE INLAND WITHIN 24 HOURS...SIGNIFICANT MOISTURE WILL REMAIN OVER THE SW GULF OF MEXICO. THE UPPER TROUGH OVER THE ERN CONUS WILL ALSO LIKELY CAUSE SHOWERS/THUNDERSTORMS OVER THE NE GULF WHILE WEAK SURFACE RIDGING WILL REMAIN OVER THE NRN GULF. CARIBBEAN SEA... AN UPPER LEVEL TROUGH COVERS THE MAJORITY OF THE WRN AND CENTRAL CARIBBEAN CENTERED AROUND AN UPPER LEVEL LOW NEAR 16N75W. WHILE THE LOW IS WRAPPING DRY AIR CLOSEST TO ITS CENTER KEEPING MUCH OF THE CENTRAL CARIBBEAN DRY AND CLEAR...A FEW ISOLATED SHOWERS ARE OVER THE WRN. A TROPICAL WAVE IS S OF ERN CUBA ALONG 75W...BUT DO TO THE AFOREMENTIONED DRY AIR ALOFT IT IS NOT CAUSING MUCH ACTIVE WEATHER EXCEPT FOR A SMALL AREA OF SHOWERS/THUNDERSTORMS W OF THE WAVE AXIS NEAR JAMAICA. A LINE OF STRONGER SHOWERS/THUNDERSTORMS IS ACROSS THE SE CARIBBEAN FROM 13N61W TO 14N71W. THESE ARE DUE TO AN AREA OF MOISTURE THAT HAS MOVED OVER THE SE CARIBBEAN AHEAD OF A TROPICAL WAVE THAT IS STILL E OF THE LESSER ANTILLES. THIS AREA IS ALSO UNDER MOIST SLY FLOW ALOFT BETWEEN THE UPPER TROUGH OVER THE WRN AND CENTRAL CARIBBEAN AND AN UPPER LEVEL RIDGE COVERING THE ERN PORTION E OF 70W. 20 KT ELY TRADEWINDS COVER THE MAJORITY OF THE BASIN. EXPECT THE TROPICAL WAVE IN THE CENTRAL CARIBBEAN TO CONTINUE TO MOVE WWD WITH POSSIBLE SHOWERS...AS ACTIVITY INCREASES IN THE ERN CARIBBEAN AS MOISTURE PRECEDES THE TROPICAL WAVE E OF THE BASIN. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH OVER THE ERN CONUS IS PUSHING SE SUPPORTING A FEW ISOLATED SHOWERS/THUNDERSTORMS OFF THE NE COAST OF FLORIDA WITHIN 200 NM. AN AREA OF SCATTERED SHOWERS/THUNDERSTORMS ARE OVER THE NW BAHAMAS ALONG A LINE FROM 23N80W TO 28N77W. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING EXTENDING FROM A 1032 MB HIGH NE OF THE AZORES ISLANDS...AND A 1023 MB HIGH NEAR 31N60W. THE RIDGE IS MAINTAINING MOSTLY FAIR CONDITIONS THROUGHT THE ENTIRE BASIN. ALOFT...AN UPPER LEVEL RIDGE EXTENDS ACROSS FLORIDA INTO THE SW ATLC TO NEAR 31N73W. AN UPPER LEVEL LOW IS SPINNING NEAR 28N52W SUPPORTING A FEW ISOLATED SHOWERS/THUNDERSTORMS FROM 27N-32N BETWEEN 55W-60W. BROAD UPPER RIDGING COVERS MUCH OF THE TROPICAL ATLC AROUND A CENTER NEAR 13N52W AND 12N29W. AN UPPER LEVEL TROUGH COVERS THE FAR E ATLC WITH AXIS JUST W OF THE CANARY ISLANDS. EXPECT SHOWER ACTIVITY TO CONTINUE OVER THE FAR WRN ATLC WITH SURFACE RIDGING CONTINUING ACROSS THE REMAINDER OF THE BASIN FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON 000 AXNT20 KNHC 301200 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU JUN 30 2011 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 FEATURE... T.S. ARLENE IS CENTERED NEAR 21.6N 97.5W AT 30/1200 UTC CURRENTLY MAKING LANDFALL NEAR CABO ROJO MEXICO MOVING W AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 993 MB. MAXIMUM SUSTAINED WIND SPEED IS 56 KT. PLEASE SEE THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. NUMEROUS MODERATE CONVECTION IS WITHIN 175 NM FROM THE CENTER OF THE STORM IN ALL DIRECTIONS. SCATTERED STRONG CONVECTION IS EMBEDDED WITHIN THIS AREA OF MODERATE CONVECTION ACROSS THE NRN HEMISPHERE WITH ISOLATED STRONG CONVECTION ALONG THE SRN HEMISPHERE. NUMEROUS MODERATE CONVECTION IS ALSO SE OF THE CENTER FROM 14N-19N BETWEEN 88W-97W WITH A CLUSTER OF STRONG CONVECTION FROM 14N-17N BETWEEN 94W-97W. ...TROPICAL WAVES... A TROPICAL WAVE IS IN THE WRN TROPICAL ATLC ALONG 54/55W FROM 7N-15N MOVING W 15-20 KT. THE WAVE REMAINS IN AN AREA OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. BROAD CYCLONIC SURFACE FLOW IS ABOUT THE WAVE AXIS. SCATTERED MODERATE/STRONG CONVECTION FROM 10N-14N BETWEEN 52W-58W. A TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN S OF ERN CUBA ALONG 75W/76W FROM 14N-20N MOVING W NEAR 10 KT. THE WAVE IS E OF AN AREA OF MODERATE MOISTURE VALUES THAT HAVE MOVED ACROSS THE WRN CARIBBEAN. THIS WAVE LOST MOST OF ITS ENERGY AFTER INTERACTING WITH AN UPPER LEVEL LOW NOW DIRECTLY OVER THE WAVE. THE UPPER LEVEL LOW IS DRAWING DRY AIR ALOFT INTO THE CENTRAL CARIBBEAN WHICH IS INHIBITING DEEP CONVECTION NEAR THE WAVE AXIS. A SMALL AREA OF SHOWERS/THUNDERSTORMS IS E OF JAMAICA FROM 18N-19N BETWEEN 75W-77W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 24N ALONG 20N7W 19N15W 13N18W 9N27W. THE ITCZ CONTINUES FROM 9N27W ALONG 8N36W 7N43W 6N53W. ISOLATED MODERATE/STRONG CONVECTION IS ALONG A SWATH FROM THE AFRICAN COAST TO 47W FROM 6N-10N. ...DISCUSSION... GULF OF MEXICO... TROPICAL STORM ARLENE CONTINUES TO IMPACT MUCH OF THE SW GULF OF MEXICO. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. HIGH LEVELS OF MOISTURE ARE ACROSS THE MAJORITY OF THE BASIN. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE OVER THE SE GULF FROM 22N-26N BETWEEN 81W089W. ALOFT... ANTI-CYCLONIC OUTFLOW FROM ARLENE IS COVERING MUCH OF THE WRN GULF. AN UPPER RIDGE AXIS ALSO EXTENDS FROM SRN LOUISIANA ACROSS CENTRAL FLORIDA AND INTO THE WRN ATLC. AN UPPER LEVEL TROUGH IS SINKING SWD OVER THE ERN CONUS AND IS JUST N OF THE NE GULF. THIS UPPER TROUGH SUPPORTS A SURFACE TROUGH EXTENDING ACROSS THE FLORIDA PANHANDLE TO 30N86W. A FEW SCATTERED SHOWERS/THUNDERSTORMS ARE S OF THE TROUGH ALONG A LINE FROM 29N83W TO 30N88W. A WEAK SURFACE RIDGE IS OVER THE N CENTRAL GULF AROUND A 1015 MB HIGH NEAR 30N88W. MODERATE DRY AIR ALOFT IS OVER THE SURFACE RIDGE. THIS COMBINATION IS PROVIDING MOSTLY FAIR CONDITIONS OVER THE NRN GULF N OF 28N W OF 84W...BESIDES THE LINE OF SHOWERS IN THE NE GULF MENTIONED PREVIOUSLY. EVEN THOUGH ARLENE WILL BE INLAND WITHIN 24 HOURS...SIGNIFICANT MOISTURE WILL REMAIN OVER THE SW GULF OF MEXICO. THE UPPER TROUGH OVER THE ERN CONUS WILL ALSO LIKELY CAUSE SHOWERS/THUNDERSTORMS OVER THE NE GULF WHILE WEAK SURFACE RIDGING WILL REMAIN OVER THE NRN GULF. CARIBBEAN SEA... AN UPPER LEVEL TROUGH COVERS THE MAJORITY OF THE WRN AND CENTRAL CARIBBEAN CENTERED AROUND AN UPPER LEVEL LOW NEAR 16N75W. WHILE THE LOW IS WRAPPING DRY AIR CLOSEST TO ITS CENTER KEEPING MUCH OF THE CENTRAL CARIBBEAN DRY AND CLEAR...A FEW ISOLATED SHOWERS ARE OVER THE WRN. A TROPICAL WAVE IS S OF ERN CUBA ALONG 75W...BUT DO TO THE AFOREMENTIONED DRY AIR ALOFT IT IS NOT CAUSING MUCH ACTIVE WEATHER EXCEPT FOR A SMALL AREA OF SHOWERS/THUNDERSTORMS W OF THE WAVE AXIS NEAR JAMAICA. A LINE OF STRONGER SHOWERS/THUNDERSTORMS IS ACROSS THE SE CARIBBEAN FROM 13N61W TO 14N71W. THESE ARE DUE TO AN AREA OF MOISTURE THAT HAS MOVED OVER THE SE CARIBBEAN AHEAD OF A TROPICAL WAVE THAT IS STILL E OF THE LESSER ANTILLES. THIS AREA IS ALSO UNDER MOIST SLY FLOW ALOFT BETWEEN THE UPPER TROUGH OVER THE WRN AND CENTRAL CARIBBEAN AND AN UPPER LEVEL RIDGE COVERING THE ERN PORTION E OF 70W. 20 KT ELY TRADEWINDS COVER THE MAJORITY OF THE BASIN. EXPECT THE TROPICAL WAVE IN THE CENTRAL CARIBBEAN TO CONTINUE TO MOVE WWD WITH POSSIBLE SHOWERS...AS ACTIVITY INCREASES IN THE ERN CARIBBEAN AS MOISTURE PRECEDES THE TROPICAL WAVE E OF THE BASIN. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH OVER THE ERN CONUS IS PUSHING SE SUPPORTING A FEW ISOLATED SHOWERS/THUNDERSTORMS OFF THE NE COAST OF FLORIDA WITHIN 200 NM. AN AREA OF SCATTERED SHOWERS/THUNDERSTORMS ARE OVER THE NW BAHAMAS ALONG A LINE FROM 23N80W TO 28N77W. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING EXTENDING FROM A 1032 MB HIGH NE OF THE AZORES ISLANDS...AND A 1023 MB HIGH NEAR 31N60W. THE RIDGE IS MAINTAINING MOSTLY FAIR CONDITIONS THROUGHT THE ENTIRE BASIN. ALOFT...AN UPPER LEVEL RIDGE EXTENDS ACROSS FLORIDA INTO THE SW ATLC TO NEAR 31N73W. AN UPPER LEVEL LOW IS SPINNING NEAR 28N52W SUPPORTING A FEW ISOLATED SHOWERS/THUNDERSTORMS FROM 27N-32N BETWEEN 55W-60W. BROAD UPPER RIDGING COVERS MUCH OF THE TROPICAL ATLC AROUND A CENTER NEAR 13N52W AND 12N29W. AN UPPER LEVEL TROUGH COVERS THE FAR E ATLC WITH AXIS JUST W OF THE CANARY ISLANDS. EXPECT SHOWER ACTIVITY TO CONTINUE OVER THE FAR WRN ATLC WITH SURFACE RIDGING CONTINUING ACROSS THE REMAINDER OF THE BASIN FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON