000 AXNT20 KNHC 202336 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON JUN 20 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IN THE ATLC IS ANALYZED FROM 12N43W TO 5N45W MOVING W 15-20 KT. THE WAVE MOVES ALONG WITH AN AREA OF ELEVATED MOISTURE VALUES IN TOTAL PRECIPITABLE WASTER IMAGERY. THE CONVECTION ASSOCIATED WITH THE WAVE REMAINS EMBEDDED IN THE ITCZ...GENERATING SCATTERED SHOWERS AND TSTMS FROM 5N-13N BETWEEN 40W-50W. TROPICAL WAVE IS MOVING ACROSS THE CENTRAL CARIBBEAN SEA ANALYZED FROM THE EASTERN EDGE OF HISPANIOLA TO INLAND OVER NW VENEZUELA NEAR 10N70W MOVING W 10-15 KT. THIS WAVE MOVES AHEAD OF A MOISTURE SURGE NOTICED ON THE TOTAL PRECIPITABLE WATER PRODUCT...AND SO THE CONVECTION REMAINS EAST OF THE AXIS BETWEEN 63W-68W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU NEAR 12N16W TO 8N17W TO 7N21W. THE ITCZ AXIS CONTINUES FORM THIS POINT ALONG 6N30W TO 8N42W. THEN...IT RESUMES W OF THE TROPICAL WAVE NEAR 8N46W TO THE COAST OF SOUTH AMERICA NEAR 9N60W. SCATTERED MODERATE CONVECTION IS WITHIN 100-150 NM ON EITHER SIDE OF THE MONSOON TROUGH AXIS. SIMILAR CONVECTION IS WITHIN 90-120 NM EITHER SIDE OF THE ITCZ BETWEEN 23W-42W. SCATTERED WEAK CONVECTION IS WITHIN 130 NM N OF THE ITCZ AXIS W OF 50W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL RIDGE COVERS THE GULF THIS EVENING WITH VERY DRY AIR ALOFT AND STRONG SUBSIDENCE NOTICED ON WATER VAPOR IMAGERY. HOWEVER...AT SURFACE...A TROPICAL WAVE MOVED INLAND INTO MEXICO IN THE AFTERNOON HOURS...ENHANCING AN AREA OF SSE TO RETURN FLOW UP TO 20 KT GUSTING TO 25 KT OBSERVED W OF 84W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EMBEDDED IN THE FLOW N OF 24N BETWEEN 88W-95W...AND ALSO N OF THE YUCATAN PENINSULA AND YUCATAN CHANNEL S OF 24N BETWEEN W83-89W. THE ACTIVITY IS EXPECTED TO SPREAD WNW OVER THE NEXT 24 HOURS...WITH NO OTHER SIGNIFICANT CHANGES EXPECTED ELSEWHERE ACROSS THE BASIN. CARIBBEAN SEA... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE NOTICED OVER THE NW CARIBBEAN...MOVING NW INTO THE GULF OF MEXICO N OF 18N W OF 81W. SIMILAR CONVECTION IS OCCURRING IN THE FAR SW BASIN S OF 12N W OF 73W DUE TO AN EXTENSION OF THE MONSOON TROUGH ACROSS CENTRAL AMERICA OVER NORTHERN COSTA RICA TO THE NORTHERN COAST OF COLOMBIA ALONG 11N. A TROPICAL WAVE IS MOVING ACROSS THE CENTRAL BASIN GENERATING CONVECTION E OF THE AXIS BETWEEN 63W-68W. OTHERWISE...FAIR WEATHER CONDITIONS WITH A FEW ISOLATED SHOWERS ARE EVIDENT ON VISIBLE SATELLITE IMAGERY...WITH MARINE OBS INDICATING EASTERLY TRADES UP TO 25 KT ACROSS MOST OF THE CARIBBEAN S OF 20N. THE STRONGEST WINDS ARE OBSERVED ALONG THE COAST OF COLOMBIA. THE CONVECTION IS THE SW BASIN IS EXPECTED TO LINGER OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... MOST OF THE ATLC WITHIN THE DISCUSSION AREA IS DOMINATED BY A BROAD UPPER LEVEL RIDGE OF HIGH PRESSURE...ANCHORED BY A 1021 MB HIGH NEAR 28N44W AND A 1022 MB HIGH NEAR 32N33W. THIS SCENARIO IS GENERATING 10-20 KT ANTI-CYCLONIC FLOW ACROSS THE AREA. NEVERTHELESS...SATELLITE DERIVED WINDS AND WATER VAPOR IMAGERY INDICATED A SHARP UPPER LEVEL TROUGH OVER THE FAR WEST ATLC GENERATING AN AREA OF WEAK SCATTERED SHOWERS COVERING MOST OF THE BAHAMAS FROM 20N-28N BETWEEN 70W-78W. ANOTHER WEAK MID-UPPER LEVEL TROUGH CUTS THROUGH THE RIDGE SUPPORTING A WEAK NEARLY STATIONARY FRONT EXTENDING ACROSS THE NE AND CENTRAL ATLC... ENTERING THE DISCUSSION AREA ALONG 32N45W ENDING NEAR 27N54W. NO ACTIVITY IS OBSERVED IN THE VICINITY OF THE BOUNDARY. A WEAK SURFACE TROUGH IS ALSO ANALYZED NEAR THE HEART OF THE RIDGE FROM 29N36W TO 22N35W WITHOUT ANY DEEP CONVECTION. NO SIGNIFICANT CHANGES ARE EXPECTED OVER THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA