000 AXNT20 KNHC 281052 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC... ...SPECIAL FEATURES... TROPICAL STORM ALEX IS CENTERED NEAR 19.7N 91.6W AT 28/0900 UTC OR ABOUT 65 NM W OF CAMPECHE MEXICO AND ABOUT 380 NM ESE OF TAMPICO MEXICO MOVING NW AT 05 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 990 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. NUMEROUS MODERATE AND STRONG CONVECTION ARE FROM 18N-21N BETWEEN 88W-92W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION ARE ELSEWHERE FROM 16N-18N BETWEEN 90W-95W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/ WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS INLAND OVER AFRICA FROM 05N-19N ALONG 12W MOVING W AT 10 KT. HOVMOLLER DIAGRAM ANALYSIS OVER THE PAST COUPLE OF DAYS SHOWS A DISTINCT CLOUD SIGNATURE MOVING WESTWARD ACROSS INTERIOR AFRICA WITH GLOBAL MODEL GUIDANCE ALSO INDICATING THE POSITION OF THE WAVE IN THE LOW-LEVEL POTENTIAL VORTICITY FIELDS. A 1007 MB LOW IS ANALYZED NEAR 16N15W AS THE NORTHERN VORTEX OF THE WAVE THAT IS FORECAST TO PASS DAKAR SENEGAL AND TRACK SOUTHEAST OF THE CAPE VERDE ISLANDS IN THE NEXT 24-36 HOURS. A LARGE SAHARAN AIR LAYER IS ALSO NOTED WEST OF THE WAVE AXIS FROM 10N-23N BETWEEN 17W-35W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 08N-14N BETWEEN 13W-18W. TROPICAL WAVE IS FROM 01N-13N ALONG 42W MOVING W 15-20 KT. LOW-LEVEL CYCLONIC FLOW IS NOTED ABOUT THE WAVE AXIS ON SATELLITE IMAGERY MAINLY S OF 10N. THE WAVE ALSO COINCIDES WITH A BROAD AREA OF MAXIMUM TOTAL PRECIPITABLE WATER FROM THE EQUATOR TO 10N BETWEEN 36W-47W. WIDELY SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 03N-08N BETWEEN 40W-44W. TROPICAL WAVE IS FROM 04N-15N ALONG 76W MOVING W NEAR 10-15 KT. THIS WAVE HAS PROGRESSED WESTWARD AT LOW-LATITUDE THE PAST FEW DAYS AND LOCATION IS BASED ON CONTINUITY ALONG WITH A VERY SMALL AREA OF ENHANCED PRECIPITABLE WATER MOVING ACROSS THE EXTREME SOUTHERN CARIBBEAN AND PORTIONS OF NORTHERN SOUTH AMERICA. SCATTERED MODERATE AND ISOLATED MODERATE CONVECTION IS FROM 11N-18N BETWEEN 74W-78W...AND IS LARGELY ENHANCED BY AN UPPER LEVEL DIFFLUENT ENVIRONMENT ACROSS THE WESTERN CARIBBEAN SEA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N14W 05N25W 04N42W 05N60W 08N70W. SCATTERED TO NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION ARE FROM 04N-08N BETWEEN 11W-23W. SIMILAR CONVECTION IS WITHIN 200 NM EITHER SIDE OF THE AXIS BETWEEN 23W-41W. ISOLATED MODERATE CONVECTION IS FROM 02N-08N BETWEEN 44W-53W. ...DISCUSSION... GULF OF MEXICO... SIGNIFICANT MOISTURE ASSOCIATED WITH TROPICAL STORM ALEX IS BEING DRAWN ACROSS MUCH OF THE GULF OF MEXICO SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS MUCH OF THE BASIN E OF 94W. ALEX IS LOCATED OVER THE OPEN WATERS OF THE EASTERN BAY OF CAMPECHE AND IS FORECAST TO TRACK SLOWLY NW OVER THE NEXT 24-36 HOURS. ELSEWHERE...A WEAK SURFACE RIDGE EXTENDS ACROSS THE CENTRAL FLORIDA PENINSULA NEAR 28N TO LOUISIANA AND EASTERN TEXAS NEAR 30N97W. ALOFT...AN UPPER LEVEL LOW IS CENTERED OVER CENTRAL ALABAMA AND EXTENDS AN UPPER LEVEL TROUGH AXIS SW FROM THE LOW OVER THE NW GULF TO 25N94W. THE REMAINDER OF THE BASIN IS UNDER THE INFLUENCE OF A MIDDLE TO UPPER LEVEL RIDGE WITH AXIS EXTENDING ALONG 20N. UPPER LEVEL DIFFLUENCE LOCATED BETWEEN THE RIDGE S OF 26N AND EAST OF THE UPPER LEVEL TROUGH IS ENHANCING NUMEROUS SHOWERS AND SCATTERED TSTMS OVER THE EASTERN GULF FROM 21N-29N BETWEEN 83W-94W. CARIBBEAN SEA... MOISTURE ASSOCIATED WITH TROPICAL STORM ALEX CONTINUES TO MAINLY AFFECT THE YUCATAN PENINSULA AND AREAS W OF 87W THIS MORNING. AN UPPER LEVEL ANTICYCLONIC CIRCULATION ENCOMPASSES THE WESTERN CARIBBEAN W OF 75W AND IS PROVIDING THIS AREA WITH NORTHERLY FLOW ALOFT. MUCH OF THIS FLOW IS LADEN WITH MOISTURE ADVECTING FROM THE EASTERN GULF OF MEXICO ACROSS CUBA INTO THE SW CARIBBEAN. AN UPPER LEVEL DIFFLUENT ENVIRONMENT ALONG WITH LOW-LEVEL CONVERGENT E-SE TRADES IS GENERATING SCATTERED SHOWERS AND TSTMS FROM 11N-18N BETWEEN 74W-78W. THE APPROACH OF THE TROPICAL WAVE ALONG 77W IS ALSO EXPECTED TO GENERATE SCATTERED SHOWERS AND TSTMS S OF 15N W OF 76W OVER THE NEXT 24-36 HOURS ACROSS THE SW CARIBBEAN AND INTERIOR PORTIONS OF CENTRAL AMERICA SOUTH OF NICARAGUA. THE CLOSE PROXIMITY OF THE ITCZ AXIS ALONG 09N IS ALSO PROVIDING FOCUS FOR SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS PANAMA AND COSTA RICA S OF 13N. THE REMAINDER OF THE CARIBBEAN SEA BASIN IS UNDER THE INFLUENCE OF AN UPPER LEVEL LOW CENTERED NORTH OF HISPANIOLA NEAR 23N68W. AN UPPER LEVEL TROUGH AXIS EXTENDS SOUTHWARD FROM THE LOW TO 13N70W AND COVERS THE CARIBBEAN E OF 75W WITH MOSTLY DRY AIR AS INDICATED ON WATER VAPOR IMAGERY. HOWEVER...SHALLOW LOW-LEVEL SHOWERS ARE OCCURRING N OF 15N E OF 73. ATLANTIC OCEAN... A SURFACE TROUGH IS NE OF THE TURKS AND CAICOS ISLANDS ALONG 19N68W TO 27N65W SUPPORTED BY A MIDDLE TO UPPER LEVEL LOW CENTERED NEAR 23N68W. SATELLITE PRESENTATION INDICATES MOISTURE AND CLOUDINESS WRAPPING AROUND THE UPPER LEVEL LOW WITH ISOLATED SHOWERS AND TSTMS COVERING THE AREA FROM 20N-28N BETWEEN 59W-72W. ELSEWHERE ACROSS THE ATLC...A BROAD SURFACE RIDGE DOMINATES ANCHORED BY A 1028 MB HIGH CENTERED SW OF THE AZORES NEAR 34N35W KEEPING GENERALLY FAIR AND STABLE CONDITIONS ACROSS THE BASIN. ALOFT...WATER VAPOR IMAGERY INDICATES A DRY AND STABLE AIRMASS ASSOCIATED WITH AN ANTICYCLONIC CIRCULATION CENTERED NEAR 15N56W ACROSS THE AREA FURTHER SUPPORTING THE FAIR WEATHER. AN UPPER LEVEL RIDGE AXIS EXTENDS NORTHWARD FROM THE CENTER ALONG 56W TO 29N E OF THE AFOREMENTIONED UPPER LEVEL LOW. NE OF THE UPPER LEVEL RIDGE...A BROAD UPPER LEVEL TROUGH COVERS THE NE ATLC DISCUSSION AREA WATERS N OF 20N E OF 47W. ACROSS THE TROPICAL ATLC...BROAD UPPER LEVEL RIDGING COVERS THE AREA S OF 20N. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN