000 AXNT20 KNHC 292354 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON JUN 28 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC... ...SPECIAL FEATURES... TROPICAL STORM ALEX IS CENTERED NEAR 23.2N 94.5W AT 30/0000 UTC MOVING WNW NEAR 11 KT. MINIMUM CENTRAL PRESSURE IS 980 MB WITH MAXIMUM SUSTAINED WIND OF 60 KT WITH GUSTS TO 75 KT. TROPICAL STORM AND HURRICANE WATCHES ARE IN EFFECT FOR PORTIONS OF NE MEXICO AND SE TEXAS. THIS SYSTEM CONTINUES TO DRAW A SIGNIFICANT AMOUNT OF DEEP LAYER MOISTURE ACROSS THE GULF OF MEXICO AND NW CARIBBEAN GENERATING NUMEROUS STRONG CONVECTION ACROSS THE YUCATAN PENINSULA FROM 18N-25N BETWEEN 88W-91W...NEAR THE CENTER FROM 21N-24N BETWEEN 92W-96W...AND JUST OFF THE COAST OF TEXAS AND LOUISIANA FROM 26N-29N BETWEEN 91W-96W. SCATTERED STRONG CONVECTION IS ALSO FROM 17N-21N BETWEEN 91W-97W....AND FROM 23N-26N BETWEEN 89W-99W. DUE TO THE LARGE AMOUNT OF RAINFALL ACCUMULATED OVER THE PAST FEW DAYS OVER THESE AREA...THE THREAT FOR FLASH FLOODING AND MUDSLIDES IS STILL HIGH ON AREAS WHERE THE TERRAIN HAS BECOME SATURATED ESPECIALLY OVER THE YUCATAN PENINSULA AND SE MEXICO. AS THE OUTER RAINBANDS AFFECT SRN TEXAS AND NE MEXICO THE POTENTIAL FOR FLASH FLOODS WILL INCREASE FOR THESE AREAS. ALEX IS EXPECTED TO CONTINUE TO INTENSIFY AND SLOWLY TURN WNW AND DECREASE ITS FORWARD MOTION AS IT APPROACHES THE NE MEXICO/SE TEXAS COAST. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS APPROACHING THE CAPE VERDE ISLANDS ALONG 18N21W TO 5N23W MOVING W 15-20 KT. THE WAVE LIES AHEAD OF A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. LOW-LEVEL CYCLONIC CURVATURE IS ALSO SEEN IN SATELLITE IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 5N-9N BETWEEN 21W-26W. TROPICAL WAVE EXTENDS FROM 10N49W TO 4N46W MOVING W 10-15 KT. LOW-LEVEL CYCLONIC FLOW IS ABOUT THE WAVE AXIS. THE WAVE ALSO COINCIDES WITH A MAXIMUM IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM EQ-7N BETWEEN 43W-50W. A SURFACE TROUGH TO THE NE OF THE WAVE ALONG 23N53W TO 12N59W MAY ORIGINATE FROM A SPLIT PIECE OF ENERGY FROM THE WAVE AFTER INTERACTION WITH A MID-LATITUDE FEATURE. THIS TROUGH MAY END UP BECOMING THE MORE DOMINATE FEATURE AS THEY BOTH PROGRESS WWD. TROPICAL WAVE EXTENDS ACROSS NICARAGUA FROM 16N84W TO 7N87W. MOVING W NEAR 10 KT. WAVE IS FOLLOWING A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY SEEN ACROSS THE NW CARIBBEAN THAT IS BEING DRAWN INTO THE CIRCULATION OF TROPICAL STORM ALEX. WHILE SOME OF THE ENERGY ASSOCIATED WITH THE WAVE WILL MOST LIKELY BE ABSORBED INTO THIS SYSTEM...MODEL DATA DOES INDICATE SOME PERTURBATION CONTINUING WWD INTO THE E PACIFIC. SCATTERED STRONG CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS FROM 9N-12N. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N13W 9N23W 4N36W 6N48W 5N57W. A LARGE AREA OF NUMEROUS STRONG CONVECTION IS MOVING OFF THE COAST OF AFRICA FROM 8N-17N BETWEEN 10W-18W. ISOLATED MODERATE/STRONG CONVECTION IS FROM 3N-7N BETWEEN 32W-34W. SIMILAR ACTIVITY IS ALONG THE AXIS BETWEEN 39W-43W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 2N-6N BETWEEN 53W-58W. ...DISCUSSION... GULF OF MEXICO... SIGNIFICANT MOISTURE ASSOCIATED WITH TROPICAL STORM ALEX IS BEING DRAWN ACROSS THE ENTIRE GULF OF MEXICO SUPPORTING AREAS OF SHOWERS/THUNDERSTORMS ACROSS THE MAJORITY OF THE BASIN. ALEX IS CURRENTLY PRODUCING NUMEROUS STRONG CONVECTION ACROSS THE YUCATAN PENINSULA FROM 18N-25N BETWEEN 88W-91W...NEAR THE CENTER FROM 21N-24N BETWEEN 92W-96W...AND JUST OFF THE COAST OF TEXAS AND LOUISIANA FROM 26N-29N BETWEEN 91W-96W. SCATTERED STRONG CONVECTION IS ALSO FROM 17N-21N BETWEEN 91W-97W....AND FROM 23N-26N BETWEEN 89W-99W. RADAR IMAGERY ALSO INDICATES SCATTERED SHOWERS/THUNDERSTORMS ACROSS THE ERN GULF OF MEXICO AFFECTING THE NE GULF STATES INCLUDING THE FLORIDA PENINSULA. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS ON ALEX. ALOFT...NW-NLY FLOW COVERS THE AREA E OF ALEX. EXPECT CONTINUED SHOWER/THUNDERSTORM ACTIVITY ACROSS MUCH OF THE BASIN AS MOISTURE WITH ALEX REMAINS ACROSS THE AREA. FOR MORE INFORMATION AND UPDATES REGARDING ALEX...VISIT OUR WEBPAGE AT WWW.NHC.NOAA.GOV. CARIBBEAN SEA... MOISTURE ASSOCIATED WITH TROPICAL STORM ALEX...AND A TROPICAL WAVE FROM ACROSS NICARAGUA CONTINUES TO AFFECT THE NW CARIBBEAN SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS W OF 75W INCLUDING MUCH OF CUBA. SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE SW CARIBBEAN S OF 9N DUE TO SURFACE CONVERGENCE NEAR A PORTION OF THE E PACIFIC ITCZ THAT EXTENDS ACROSS COSTA RICA...AND PANAMA TO NRN COLOMBIA. ISOLATED SHOWERS/THUNDERSTORMS HAVE ALSO FLARED UP OVER NRN HISPANIOLA AND PUERTO RICO MOST LIKELY ENHANCED BY THE COMBINATION OF DAYTIME HEATING AND UPPER LEVEL SUPPORT FROM AN UPPER LEVEL LOW SPINNING N OF THE BAHAMAS NEAR 26N74W. THE REMAINDER OF THE CENTRAL AND ERN CARIBBEAN IS INFLUENCED BY DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE CENTERED NEAR 16N62W KEEPING CONDITIONS FAIR. EXPECT MOISTURE AND WINDY CONDITIONS TO REMAIN ACROSS THE NW CARIBBEAN INFLUENCED BY TROPICAL STORM ALEX. ALSO EXPECT SHOWER/THUNDERSTORM ACTIVITY TO INCREASE ACROSS THE LESSER ANTILLES AS A SURFACE TROUGH E OF THE ISLANDS MOVES WWD. ATLANTIC OCEAN... A SURFACE TROUGH IS N OF TURKS AND CAICOS FROM 30N71W TO 25N72W SUPPORTED BY A MID-UPPER LEVEL LOW NEAR 26N74W. WIDELY ISOLATED SHOWERS/THUNDERSTORMS ARE FROM 20N-31N BETWEEN 65W-76W. A SECOND SURFACE TROUGH IS ALONG 62W FROM 24N-30N ENHANCING ISOLATED SHOWERS WITHIN 90 NM EITHER SIDE OF THE AXIS. A THIRD...AND LARGER...SURFACE TROUGH IS E OF THE LESSER ANTILLES ALONG 23N53W TO 12N59W. THIS TROUGH MAY HAVE ORIGINATED FROM A SPLIT PIECE OF ENERGY FROM A TROPICAL WAVE TO ITS SE. THE TROUGH PRECEDES AN AREA OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. IT IS POSSIBLE THAT THIS TROUGH WILL GAIN DOMINANCE OVER THE TROPICAL WAVE AS IT MOVES WWD WITH THE POTENTIAL TO FLAIR UP SHOWERS/THUNDERSTORMS ACROSS THE LESSER ANTILLES AND NE CARIBBEAN ISLANDS. ELSEWHERE ACROSS THE ATLANTIC...A BROAD SURFACE RIDGE DOMINATES ANCHORED BY A 1030 MB AZORES HIGH NEAR 34N43W KEEPING CONDITIONS FAIR ACROSS THE BASIN. ALOFT...WATER VAPOR IMAGERY INDICATES A DRY AND STABLE AIRMASS ACROSS THE ERN HALF OF THE BASIN FURTHER SUPPORTING THE FAIR WEATHER. AN UPPER LEVEL RIDGE EXTENDS BETWEEN 55W-68W WITH A CIRCULATION CENTER NEAR 16N62W...AND 36N55W E OF THE AFOREMENTIONED UPPER LEVEL LOW. A SECOND UPPER LEVEL TROUGH EXTENDS FROM 31N26W TO 23N55W. AN UPPER LEVEL RIDGE CENTERED OVER NW AFRICA NEAR 20N16W COVERS THE REMAINDER OF THE BASIN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON