000 AXNT20 KNHC 012359 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED AUG 01 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...SPECIAL FEATURES... THE SURFACE LOW IN THE TROPICAL ATLC HAS NOW BECOME TROPICAL DEPRESSION FIVE. AS OF 0000 UTC...T.D. FIVE IS CENTERED NEAR 12.4N 49.8W...ABOUT 660 NM E OF THE WINDWARD ISLANDS...MOVING WNW AT 16 KT. MINIMUM CENTRAL PRESSURE IS 1008 MB WITH MAXIMUM WIND SPEEDS OF 30 KT WITH GUSTS TO 40 KT. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS FROM 9N-13N BETWEEN 47W-51W. UPPER LEVEL SHEAR IS CURRENTLY IMPACTING THE SYSTEM AND WILL ALLOW FOR ONLY SLOW DEVELOPMENT OVER THE NEXT COUPLE OF DAYS. INTERESTS IN THE LESSER ANTILLES SHOULD MONITOR THE PROGRESS OF T.D. FIVE. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 15N30W TO 8N30W MOVING W AT 15-20 KT. THE WAVE LIES ON THE W SIDE OF A LOW-AMPLITUDE SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. A CLEARING IN THE SAHARAN AIR LAYER AND WIDESPREAD DUST TO THE N OF THE WAVE INDICATES THE PRESENCE OF THE WAVE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-9N BETWEEN 26W-30W. TROPICAL WAVE IS PUSHING THROUGH THE CENTRAL BAHAMAS AND CENTRAL CARIBBEAN FROM 25N74W TO 11N77W MOVING W NEAR 12 KT. TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT THE WAVE LIES ON THE W SIDE OF A LARGE SURGE OF DEEP LAYER MOISTURE THAT COVERS THE N CENTRAL CARIBBEAN AND MUCH OF THE WESTERN BAHAMAS. LARGE CLUSTERS OF STRONG CONVECTION HAVE FORMED NEAR THE WAVE AXIS FROM 18N-19N BETWEEN 76W-79W ACROSS JAMAICA...AND FROM 20N-21N BETWEEN 76W-79W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALSO FARTHER E FROM 15N-20N BETWEEN 67W-74W ACROSS MUCH OF HISPANIOLA. ISOLATED MODERATE CONVECTION IS FROM 20N-26N BETWEEN 65W-74W ACROSS MUCH OF THE WESTERN BAHAMAS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF MAURITANIA AT 19N16W OVER ATLC WATERS ALONG 8N30W 10N43W. THE ITCZ BEGINS E OF WHAT IS NOW T.D. FIVE ALONG 11N52W TO 7N60W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-11N BETWEEN 13W-19W...FROM 6N-8N BETWEEN 34W-37W...AND FROM 8N-11N BETWEEN 56W-59W. STRONG CONVECTION IS ALSO S OF THIS AREA ACROSS INLAND SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... WEAK SURFACE RIDGING AROUND A 1018 MB HIGH NEAR 24N88W IS ACROSS THE GULF OF MEXICO THIS EVENING. LIGHT ANTI-CYCLONIC FLOW IS AROUND THE HIGH CENTER. HOWEVER...SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE IMPACTING THE CENTRAL GULF NEAR THE HIGH CENTER FROM 24N-27N BETWEEN 86W-93W ASSOCIATED WITH A MID-LEVEL TROUGH ACROSS THE NE GULF. AN UPPER LEVEL TROUGH EXTENDING DOWN THE EASTERN SEABOARD IS ALSO SUPPORTING A SURFACE TROUGH OVER THE FLORIDA PANHANDLE. SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS MUCH OF THE PANHANDLE AND SOUTHERN ALABAMA. SHOWERS/THUNDERSTORMS ARE ALSO ACROSS PORTIONS OF S FLORIDA. THE REMAINDER OF THE BASIN IS MOSTLY CLEAR DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE COVERING THE BASIN CENTERED OVER TEXAS...WHICH SUPPORTS THE SURFACE RIDGE. EXPECT LITTLE CHANGE OVER THE NEXT 24 HOURS. MOISTURE ASSOCIATED WITH A TROPICAL WAVE IN THE CENTRAL CARIBBEAN WILL BEGIN TO IMPACT THE SE GULF LATER IN THE WEEK AND OVER THE WEEKEND. CARIBBEAN SEA... AN ACTIVE TROPICAL WAVE IS BRINGING THE N CENTRAL CARIBBEAN SHOWERS/THUNDERSTORMS COVERING MUCH OF HISPANIOLA...JAMAICA...AND EASTERN CUBA. THE REMAINDER OF THE BASIN IS FAIRLY DRY BESIDES A FEW AFTERNOON STORMS OVER CENTRAL AMERICA. MORE SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS COSTA RICA AND PANAMA ASSOCIATED WITH THE E PACIFIC MONSOON TROUGH EXTENDING THROUGH THE COUNTRIES TO A 1008 MB LOW OVER NRN COLOMBIA. A DRY UPPER LEVEL TROUGH IS OVER WESTERN CUBA AND THE NW CARIBBEAN...WHICH MAY BE ENHANCING SOME OF THE ACTIVITY ACROSS EASTERN CUBA. BROAD UPPER LEVEL RIDGING COVERS THE REMAINDER OF THE BASIN. EXPECT THE WAVE TO CONTINUE TO MOVE WESTWARD DRAWING MOISTURE BEHIND IT. THE EASTERN CARIBBEAN SHOULD MONITOR THE PROGRESS OF T.D. FIVE IN THE TROPICAL ATLC. SEE SPECIAL FEATURES ABOVE. ATLANTIC OCEAN... A FEW SHOWERS/THUNDERSTORMS ARE OFFSHORE OF FLORIDA ASSOCIATED WITH AN UPPER LEVEL TROUGH EXTENDING DOWN THE EASTERN SEABOARD. MOST OF THE ACTIVITY IS N OF THE DISCUSSION AREA OF INLAND OVER FLORIDA. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE EASTERN BAHAMAS S OF 26N BETWEEN 64W-75W ASSOCIATED WITH AN AREA OF MOISTURE TRAILING A TROPICAL WAVE EXTENDING THROUGH THE CENTRAL BAHAMAS TO THE CENTRAL CARIBBEAN. AN UPPER LEVEL LOW CENTERED NEAR 31N65W IS ALSO SPORTING A FEW ISOLATED SHOWERS/THUNDERSTORMS FROM 27N-30N BETWEEN 58W-61W. AN UPPER LEVEL RIDGE IS TO THE NE CENTERED NEAR 37N56W SUPPORTING A 1024 MB SURFACE HIGH NEAR 34N60W. FARTHER E...ANOTHER UPPER LEVEL LOW CENTERED NEAR 28N45W SUPPORTS A SURFACE TROUGH ALONG 33N48W TO 26N55W. POSSIBLE ISOLATED SHOWERS ARE NEAR THE TROUGH AXIS. THE REMAINDER OF THE EASTERN ATLC IS DOMINATED BY SURFACE RIDGING AROUND A 1025 MB HIGH...WHICH IS PROVIDING MOSTLY FAIR CONDITIONS. THE HIGH IS SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED NEAR 22N32W WITH RIDGE AXIS EXTENDING FARTHER TO THE N...N OF THE AZORES ISLANDS. SATELLITE IMAGERY CONTINUES TO SHOW A LARGE AREA OF SAHARAN DUST THAT EXTENDS FROM THE COAST OF AFRICA TO NEAR 40W...WHICH FURTHER SUPPORTS FAIR WEATHER. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON