000 AXNT20 KNHC 300556 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI MAY 30 2008 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...SPECIAL FEATURE... TROPICAL STORM ALMA IS INLAND OVER SW HONDURAS CENTERED NEAR 13.9N 87.3W AT 30/0600 UTC WHICH IS ABOUT 9 NM SSW OF TEGUCIGALPA HONDURAS MOVING N AT 8 KT. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 40 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. ALMA IS EXPECTED TO CONTINUE MOVING N THEN MORE TO THE NW OVER THE NEXT COUPLE OF DAYS CLIPPING THE GULF OF HONDURAS LATE FRI/EARLY SAT BEFORE MOVING ACROSS BELIZE AND GUATEMALA AS A REMNANT LOW. ALTHOUGH THE WINDS WILL WEAKEN DUE TO ITS INTERACTION WITH LAND...HEAVY RAINFALL WILL CONTINUE OVER PORTIONS OF COSTA RICA...NICARAGUA...HONDURAS...EL SALVADOR... GUATEMALA...AND BELIZE AS A STEADY STREAM OF TROPICAL MOISTURE LIFTS N FROM THE PACIFIC. TOTAL RAINFALL ACCUMULATIONS OF 10-15 IN ARE POSSIBLE WITH ISOLATED AMOUNTS UP TO 20 IN...ESPECIALLY OVER THE HIGHER TERRAIN...INCREASING THE LIKELIHOOD OF FLASH FLOODS AND MUD SLIDES. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP1/WTPZ31 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 31W/32W S OF 16N MOVING W 10-15 KT. MIMIC-TPW SHOWS A WELL-DEFINED DEEP-LAYERED MOISTURE SURGE EXTENDING FROM THE TROPICS NWD TO ABOUT 14N EVEN THOUGH THERE IS VERY LITTLE SIGNATURE ON SATELLITE IMAGERY. ANY CONVECTION IS CONCENTRATED ALONG THE ITCZ AXIS. TROPICAL WAVE IS ALONG 47W/48W S OF 8N MOVING W 10-15 KT. THIS POSITION IS BASED PRIMARILY ON MIMIC-TPW. THE WAVE IS AT A VERY LOW AMPLITUDE AND SO EMBEDDED WITHIN THE ITCZ...SATELLITE SIGNATURE IS INDISCERNIBLE. ANY CONVECTION IS CONCENTRATED ALONG THE ITCZ AXIS. TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 73W/74W S OF 20N MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN AN EXTREMELY MOIST ENVIRONMENT ASSOCIATED WITH THE TROPICAL STORM ALMA. THE AXIS REMAINS DIFFICULT TO LOCATED. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS INLAND OVER NW VENEZUELA/N COLOMBIA. TROPICAL WAVE THAT WAS ALONG 85W HAS BEEN DROPPED FROM THE 30/0000 UTC ANALYSIS IN FAVOR OF THE SURFACE TROUGH. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 3N22W 6N30W 4N36W 3N47W. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 5N-8N BETWEEN 12W-14W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 8N TO S OF THE EQUATOR BETWEEN 10W-15W...FROM 1N-7N BETWEEN 25W-44W...AND FROM 3N-7N BETWEEN 44W AND THE COAST OF SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... AN UPPER HIGH REMAINS CENTERED ALONG THE PACIFIC COAST OF MEXICO NEAR MAZATLAN BUT THE RIDGE AXIS WITH THE AXIS EXTENDING NW TO E TEXAS. A NARROW INVERTED UPPER TROUGH AXIS NOW EXTENDS ACROSS THE GULF FROM CENTRAL FLORIDA TO TUXPAN MEXICO WITH A DEEP LAYERED TROUGH EXTENDING OVER THE NE GULF AND THE ASSOCIATED FRONTAL BOUNDARY INLAND OVER S GEORGIA. BROAD UPPER RIDGE ASSOCIATED WITH TROPICAL STORM ALMA COVERS THE S GULF FROM THE CENTRAL BAY OF CAMPECHE NEAR 18N95W ALONG 23N87W TO OVER S FLORIDA. MODERATE/STRONG SUBSIDENCE LIES NW OF THE UPPER RIDGE WHILE DEEP MOISTURE IS INCREASING FROM THE S OVER THE CARIBBEAN. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EMBEDDED IN THE DEEP LAYER MOISTURE FROM THE E BAY OF CAMPECHE ACROSS THE YUCATAN AND THE YUCATAN CHANNEL TO W CUBA BUT OTHERWISE MOST OF THE AREA IS EXPERIENCING FAIR WEATHER. A SURFACE RIDGE EXTENDS FROM THE W ATLC COVERING THE N GULF COVERING THE E US. CARIBBEAN... TROPICAL STORM ALMA IS INLAND OVER CENTRAL AMERICA AND IS ADVECTING DEEP TROPICAL MOISTURE FROM OVER THE FAR E PACIFIC ACROSS MUCH OF THE CARIBBEAN W OF 70W. UPPER LEVEL OUTFLOW IS SPREADING AWAY FROM ALMA WITH THE ASSOCIATED UPPER HIGH COVERING THE ENTIRE CARIBBEAN. A SURFACE TROUGH...PREVIOUSLY A TROPICAL WAVE...EXTENDS FROM INLAND OVER HONDURAS NEAR 14N86W ALONG 17N85W TO JUST S OF THE CAYMAN ISLANDS NEAR 19N80W. SCATTERED STRONG CONVECTION IS SE OF THE SURFACE TROUGH WITHIN 90 NM OF LINE FROM 13N82W TO 17N85W AND CLUSTERS OF SCATTERED MODERATE/ STRONG CONVECTION FROM 17N-20N BETWEEN 80W-85W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS COVER THE GREATER ANTILLES AND THE ADJACENT COASTAL WATERS FROM OVER HISPANIOLA THROUGH THE YUCATAN CHANNEL TO OVER THE YUCATAN PENINSULA. SCATTERED CLUSTERS OF SIMILAR ACTIVITY DOTS THE REMAINDER OF THE CARIBBEAN W OF 80W. MOSTLY CLEAR SKIES COVER THE E CARIBBEAN WITH SOME HIGH CIRRUS CLOUDS OVER PUERTO RICO AND THE VIRGIN ISLANDS. ATLANTIC... DEEP LAYERED TROUGH IS DIPPING S OVER THE W ATLC N OF 27N W OF 72W INTO THE NE GULF OF MEXICO. THE ASSOCIATED STATIONARY FRONT ENTERS THE W ATLC NEAR 32N72W ALONG 31N W OF 75W INTO S GEORGIA. A SURFACE TROUGH...REMNANTS OF AN OLD FRONTAL BOUNDARY EXTENDS FROM 27N73W ACROSS THE N BAHAMA ISLANDS TO THE N COAST OF CUBA NEAR 22N79W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 75 NM OF THE TROUGH AXIS. AN UPPER RIDGE EXTENDS FROM NEAR 25N70W NE TO BEYOND 32N61W. A WEAK SURFACE RIDGE COVERS THE REMAINDER OF THE W ATLC WITH A 1021 MB HIGH NEAR 29N69W. A SECOND SURFACE TROUGH...PREVIOUSLY A PORTION OF A TROPICAL WAVE...EXTENDS FROM 25N67W TO N OF HISPANIOLA NEAR 21N71W GENERATING SCATTERED SHOWERS/THUNDERSTORMS FROM 20N-25N BETWEEN 66W-72W. VERY LITTLE REMAINS OF THE UPPER TROUGH THAT WAS IN THE CENTRAL ATLC 24 HOURS AGO. A BROAD UPPER TROUGH EXTENDS FROM THE NE ATLC THROUGH 32N21W ALONG 26N34W TO 23N50W. AN UPPER HIGH IS IN THE E TROPICAL ATLC BETWEEN THE COAST OF W AFRICA AND THE CAPE VERDE ISLANDS WITH THE UPPER RIDGE AXIS EXTENDING W ACROSS THE TROPICAL ATLC AND IS PULLING SOME UPPER LEVEL MOISTURE FROM THE TROPICS BACK TOWARDS AFRICA. HOWEVER...DEEP MOISTURE REMAINS SCANT E OF 60W AND THUS ALL DEEP CONVECTION IS LIMITED TO THE ITCZ. A THIRD SURFACE TROUGH SEPARATES THE SUBTROPICAL SURFACE RIDGE EXTENDING FROM 32N58W TO 27N66W WITH WITH THE EASTERN PORTION ANCHORED BY A 1025 MB HIGH NEAR 32N40W. $$ WALLACE