000 AXNT20 KNHC 132352 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI MAY 13 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...ITCZ... THE ITCZ AXIS IS ANALYZED FROM THE COAST OF SIERRA LEONE NEAR 8N13W SOUTHWESTWARD ALONG 5N20W 3N30W EQ37W 1N43W TO NE BRAZIL ALONG 2S50W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 5S-6N BETWEEN 30W-45W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL SHORT WAVE MOVING ACROSS THE NORTHERN HALF OF THE GULF. THIS UPPER FEATURE IS ENHANCING LOW LEVEL CONVERGENCE ALONG A SURFACE TROUGH AXIS ANALYZED FROM THE SOUTHERN COAST OF ALABAMA NEAR 30N88W TO 27N89W. DOPPLER RADAR IMAGERY SHOWS SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS AFFECTING THE COASTAL WATERS OF MISSISSIPPI...ALABAMA...AND THE FLORIDA PANHANDLE N OF 28N BETWEEN 85W-89W. THIS AREA OF CONVECTION WILL CONTINUE TO MOVE EASTWARD AFFECTING THE NE BASIN OVER THE NEXT 24 HOURS. NO SIGNIFICANT WEATHER IS OCCURRING ELSEWHERE ACROSS THE DISCUSSION AREA. HAZY SKIES ARE NOTED ON THE SW BASIN S OF 24N W OF 90W ON VISIBLE SATELLITE IMAGERY...DUE TO SEVERAL WILD FIRES IN THE NE AND EASTERN YUCATAN PENINSULA. SURFACE OBSERVATIONS NEAR THE MEXICAN COAST BETWEEN 87W-96W ARE REPORTING VISIBILITIES DOWN TO 5 SM DUE TO THE CONCENTRATION OF HAZE IN THIS REGION. THE NEXT COLD FRONT...CURRENTLY MOVING ACROSS E TEXAS...IS EXPECTED TO ENTER THE NW GULF WATERS LATE TONIGHT INTO EARLY SATURDAY MORNING WITH NORTHERLY WINDS IN THE RANGE OF 15 TO 20 KT. CARIBBEAN SEA... AN UPPER LEVEL TROUGH MOVES ACROSS THE NORTH CENTRAL AND NE PORTIONS OF THE CARIBBEAN THIS EVENING. DRY AIR ALOFT ACCOMPANIES THE TROUGHING N OF 14N W OF 68W...WITH MOST UPPER LEVEL MOISTURE AND CLOUDINESS SUPPRESSED S OF 13N OVER COSTA RICA...PANAMA...AND NORTHERN SOUTH AMERICA. THE UPPER LEVEL TROUGH IS INDUCING BROAD CYCLONIC TURNING COVERING THE EASTERN BASIN E OF 74W. THIS SCENARIO IS SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS WITHIN 50 NM ON EITHER SIDE OF A SURFACE TROUGH ANALYZED FROM THE ATLC BASIN ACROSS THE LESSER ANTILLES ALONG 18N63W...EXTENDING SW TO THE COASTAL WATERS OF COLOMBIA NEAR 13N73W. THIS SURFACE TROUGH HAS DISRUPTED TYPICAL EASTERLY TRADES ACROSS THE CENTRAL PORTION OF THE BASIN...AND GLOBAL MODEL GUIDANCE INDICATES THIS SYNOPTIC SETUP WILL REMAIN IN PLACE OVER THE NEXT FEW DAYS. TOTAL PRECIPITABLE WATER VALUES REMAIN MODERATE OVER THE FAR SW BASIN. A SURFACE 1009 MB LOW IS ANALYZED OFF THE COAST OF PANAMA NEAR 10N78W. A SURFACE TROUGH EXTENDS SW FROM THE LOW CENTER ACROSS PANAMA INTO THE EAST TROPICAL PACIFIC OCEAN...GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS S OF 11N W OF 75W. THIS AREA OF CONVECTION IS EXPECTED TO LINGER OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A DEEP LAYERED LOW IS OVER THE WESTERN N ATLC ROTATING AROUND 36N60W. THIS SYSTEM SUPPORTS A MIDDLE TO UPPER LEVEL TROUGH AXIS EXTENDING SW ACROSS THE W ATLC INTO THE CARIBBEAN SEA. THIS SCENARIO IS GENERATING A BROAD AREA OF WIDELY SCATTERED SHOWERS AND THUNDERSTORMS N OF 17N BETWEEN 48W-63W. A BROAD AND ELONGATED AREA OF DIFFLUENCE FLOW ALOFT ASSOCIATED TO A FAIRLY STRONG 90 KT UPPER LEVEL JET STREAK FURTHER SUPPORTS THE CONVECTION IN THIS REGION. WITHIN THIS AREA OF CONVECTION... A SURFACE TROUGH IS ANALYZED FROM 20N57W INTO THE CARIBBEAN ALONG 18N63W. A SECONDARY SURFACE TROUGH IS ANALYZED FROM 29N53W 24N60W 22N66W. SCATTERED WEAK SHOWERS ARE WITHIN 20 NM ON EITHER SIDE OF THE TROUGH. SURFACE RIDGING COVERS THE REMAINDER OF THE EASTERN ATLC. A WEAK SURFACE TROUGH ANALYZED FROM 25N43W TO 21N45W IS EMBEDDED WITHIN THE SURFACE RIDGE AND CONTINUES TO DRIFT SLOWLY W-NW. A 1010 MB LOW IS NW OF THE CANARY ISLANDS NEAR 30N18W PRODUCING NO SIGNIFICANT CONVECTION. THIS LOW IS EXPECTED TO REMAIN STATIONARY AND LOOSE UPPER LEVEL SUPPORT IN THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA