000 AXNT20 KNHC 070548 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI MAY 07 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 0545 UTC... ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 37W FROM THE EQUATOR TO 10N MOVING WESTWARD AT 12 KT. TOTAL PRECIPITABLE WATER VALUES ARE ELEVATED NEAR THE WAVE AXIS. SCATTERED SHOWERS ARE ALSO WITHIN 80 NM OF THE WAVE AXIS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N13W 5N20W 3N30W 2N40W TO THE EQUATOR NEAR 50W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM THE EQUATOR TO 8N BETWEEN 15W AND 23W. WIDELY SCATTERED WEAK CONVECTION WITHIN 50 NM ON EITHER SIDE OF THE ITCZ BETWEEN 24W AND 34W. ...DISCUSSION... GULF OF MEXICO... A DRY AND STABLE AIRMASS CONTINUES TO DOMINATE MOST OF THE REGION NOTED BY STRONG SUBSIDENCE ON THE WATER VAPOR IMAGERY MOSTLY CLEAR SKIES ON THE VISIBLE IMAGERY. THIS AIRMASS IS KEEPING DEEP STRONG CONVECTION FROM DEVELOPING. ONLY THE REMNANTS OF A SURFACE TROUGH CONTINUES TO BRING SOME INSTABILITY TO THE NORTHEAST GULF INCLUDING THE NORTHERN FLORIDA PENINSULA. THIS TROUGH IS ANALYZED CROSSING THE CENTRAL FLORIDA PENINSULA FROM EAST TO WEST...ENTERING THE GULF NEAR 28N83W TO 25N87W. BRIEF ISOLATED WEAK SHOWERS ARE POSSIBLE WITHIN 30 NM ON EITHER SIDE OF THE TROUGH. COMPUTER MODELS INDICATE SOME WEAK CONVECTION MAY LINGER OVER THE NORTHEAST BASIN AND NORTHERN FLORIDA THROUGH LATE FRIDAY. ALSO...THE COMBINATION OF DIURNAL HEATING...AVAILABLE LOW LEVEL MOISTURE...AND INSTABILITY OVER THE SOUTHERN FLORIDA PENINSULA MAY RESULT IN AFTERNOON SHOWERS AND POSSIBLE THUNDERSTORMS SOUTH OF 27N. MARINE OBSERVATIONS SHOW A VERY WEAK SURFACE PRESSURE GRADIENT ACROSS THE GULF. CARIBBEAN SEA... AN UPPER LEVEL LOW IS OVER THE FAR SOUTHWESTERN CORNER OF THE BASIN NOTED BY EVIDENT CYCLONIC ROTATION JUST OFF THE CENTRAL COAST OF NICARAGUA. THIS FEATURE IS PRODUCING AN AREA OF SURFACE CONVERGENCE THAT IS BRINGING SCATTERED MODERATE TO STRONG CONVECTION WITHIN 200 NM OFF THE COAST OF NICARAGUA AND COSTA RICA. FURTHERMORE...THIS FEATURE HAS BEEN MOVING MID/UPPER LEVEL MOISTURE ACROSS JAMAICA AND EASTERN CUBA. THUS...THIS AVAILABLE MOISTURE COMBINED WITH DIURNAL HEATING AND OROGRAPHIC EFFECT WILL PRODUCE SHOWERS AND POSSIBLE THUNDERSTORMS OVER THIS AREAS. SOME LOCALIZED FLOODING MAY BE POSSIBLE IN AREAS WHERE THE TERRAIN HAS BECOME SATURATED. A WEAK SURFACE TROUGH IS OVER THE FAR NORTHEAST BASIN PRODUCING SCATTERED SHOWERS NORTH OF 15N EAST OF 65W. SCATTERED SHOWERS ARE ALSO NOTED OVER THE CENTRAL BASIN FROM 14 TO 17 BETWEEN 66W AND 72W. ELSEWHERE OUTSIDE THESE AREAS OF ACTIVE WEATHER...DRY AND STABLE AIR ALOFT IS NOTED ON WATER VAPOR IMAGERY SUPPORTING FAIR WEATHER. MARINE OBSERVATIONS SHOW EASTERLY WINDS 10 TO 20 KT ACROSS THE BASIN WITH STRONGEST WINDS OVER THE NORTH COAST OF COLOMBIA. ATLANTIC OCEAN... AN AREA OF SURFACE CONVERGENCE IS NOTED FROM 17N TO 23N BETWEEN 55W AND 60W. SCATTERED MODERATE TO HEAVY SHOWERS ARE POSSIBLE IN THIS REGION. THE REMNANTS OF A SURFACE TROUGH CONTINUE TO PRODUCE WEAK CONVECTION OVER THE FAR WESTERN BASIN NORTH OF 28N WEST OF 70W. THE TAIL END OF A COLD FRONT IS OVER THE NORTH CENTRAL ATLANTIC FROM 32N33W TO 28N42W. WEAK SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT. NO SIGNIFICANT ACTIVITY IS DEVELOPING ELSEWHERE OUTSIDE THESE AREAS OF ACTIVE WEATHER...DUE TO AN UPPER LEVEL RIDGE OVER THE WEST AND CENTRAL BASIN SUPPORTING A NEARLY STATIONARY 1020 MB HIGH CENTERED NEAR 33N50W. OVER THE NEXT 24 HOURS EXPECT THE FRONT TO MOVE SOUTHEAST WITH SHOWERS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA