000 AXNT20 KNHC 280558 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC... ...SPECIAL FEATURES... TROPICAL STORM ALEX IS CENTERED NEAR 19.4N 91.3W AT 28/0300 UTC OR ABOUT 50 NM WSW OF CAMPECHE MEXICO AND ABOUT 410 NM ESE OF TAMPICO MEXICO MOVING WNW AT 06 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 991 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM OF THE CENTER AND ALSO ACROSS THE NORTHERN YUCATAN PENINSULA FROM 19N-22N BETWEEN 88W-91W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/ WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS INLAND OVER AFRICA FROM 06N-20N ALONG 11W MOVING W AT 10-15 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. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 11N-16N BETWEEN 11W-15W. TROPICAL WAVE IS FROM 01N-16N ALONG 40W 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 35W-46W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 01N-11N BETWEEN 37W-44W. TROPICAL WAVE IS FROM 04N-15N ALONG 75W MOVING W NEAR 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. ISOLATED MODERATE CONVECTION IS S OF 14N BETWEEN 70W-77W... INCLUDING INLAND PORTIONS OF NW VENEZUELA AND NORTHERN COLOMBIA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N14W 03N30W 04N40W 03N57W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 03N-08N BETWEEN 11W-22W. SIMILAR CONVECTION IS FROM 01N-07N BETWEEN 22W-38W. ISOLATED MODERATE CONVECTION IS FROM 01N-08N BETWEEN 44W-52W. ...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 93W. ALEX HAS EMERGED OVER THE OPEN WATERS OF THE EASTERN BAY OF CAMPECHE AND IS FORECAST TO TRACK SLOWLY W-NW OVER THE NEXT 24-36 HOURS. ELSEWHERE...A WEAK SURFACE RIDGE IS ALONG 29N AND EXTENDS FROM THE W ATLC TO THE TEXAS GULF COAST NEAR GALVESTON. ALOFT...AN UPPER LEVEL LOW IS CENTERED OVER CENTRAL MISSISSIPPI AND EXTENDS AN UPPER LEVEL TROUGH AXIS SW FROM THE LOW TO 26N94W. 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 25N AND EAST OF THE UPPER LEVEL TROUGH IS ENHANCING THE SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE EASTERN GULF FROM 23N-29N BETWEEN 83W-91W. CARIBBEAN SEA... MOISTURE ASSOCIATED WITH TROPICAL STORM ALEX CONTINUES TO AFFECT MAINLY THE YUCATAN PENINSULA AND AREAS W OF 86W THIS EVENING. 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 ARE GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 14N-19N BETWEEN 75W-79W. THE APPROACH OF THE TROPICAL WAVE ALONG 75W IS ALSO EXPECTED TO GENERATING SCATTERED SHOWERS AND TSTMS S OF 15N W OF 75W 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 10N 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 EASTERN HISPANIOLA NEAR 22N68W. AN UPPER LEVEL TROUGH AXIS EXTENDS SOUTHWARD FROM THE LOW TO 12N68W AND COVERS THE CARIBBEAN E OF 75W WITH MOSTLY DRY AIR AS NOTED ON WATER VAPOR IMAGERY. HOWEVER...SHALLOW LOW-LEVEL SHOWERS ARE OCCURRING NE OF A LINE FROM SE PUERTO RICO NEAR 18N66W TO GUADELOUPE NEAR 16N62W. ATLANTIC OCEAN... A SURFACE TROUGH IS N OF PUERTO RICO ALONG 27N67W TO 21N68W SUPPORTED BY A MIDDLE TO UPPER LEVEL LOW CENTERED NEAR 22N68W. SATELLITE PRESENTATION INDICATES MOISTURE AND CLOUDINESS CURLING AROUND THE UPPER LEVEL LOW WITH ISOLATED SHOWERS AND TSTMS COVERING THE AREA FROM 18N-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 35N37W 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 15N54W ACROSS THE AREA FURTHER SUPPORTING THE FAIR WEATHER. AN UPPER LEVEL RIDGE AXIS EXTENDS NORTHWARD FROM THE CENTER ALONG 54W TO 30N 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 45W. 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