000 AXNT20 KNHC 211024 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN MAY 21 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 27W S OF 7N MOVING W 15 KT. THIS LOW-LATITUDE WAVE IS EMBEDDED WITHIN THE ITCZ. THERE IS SOME CYCLONIC TURNING ASSOCIATED WITH THIS WAVE BUT IT IS RATHER BROAD AND LESS DISCERNIBLE THAN YESTERDAY. THE WAVE WILL LIKELY REMAIN ILL DEFINED AS IT MOVES WESTWARD IN A DRY ENVIRONMENT. TROPICAL WAVE IS ALONG 52W S OF 7N MOVING W 15-20 KT. THIS WAVE STILL HAS SOME SIGNATURE OF AN INVERTED V-PATTERN EMBEDDED WITHIN THE ITCZ. MUCH OF THE WAVE IS NOW INLAND OVER S AMERICA. SCATTERED MODERATE CONVECTION IS WITHIN 180 NM W OF THE WAVE AXIS FROM 5N-8N. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE ELSEWHERE. LITTLE IMPACT IS EXPECTED IN THE CARIBBEAN FROM THIS WAVE OVER THE NEXT 3-5 DAYS AS THE MAJORITY OF THE MOISTURE IS EXPECTED TO MOVE ACROSS S AMERICA. TROPICAL WAVE ALONG 87W S OF 13N MOVING W 10-15 KT. THIS WAVE IS MAINLY IN THE EPAC BUT ITS NORTHERN EXTENSION LIES OVER CENTRAL AMERICA. A WEAK BROAD 1009 MB LOW HAS DEVELOPED ALONG THE WAVE AXIS NEAR 9N. THE WAVE IN CONJUNCTION WITH STRONG SWLY FLOW AND A SFC TROUGH IS PRODUCING CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ACROSS THE SW CARIBBEAN AND CENTRAL AMERICA. THIS FEATURE IS NOT EXPECTED TO BECOME MUCH BETTER DEFINED OVER THE NEXT COUPLE OF DAYS AS MOVES FURTHER W ACROSS THE EPAC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N13W 3N25W 2N40W 4N51W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 20W-28W ASSOCIATED WITH THE TROPICAL WAVE ALONG 27W. SIMILAR CONVECTION IS WITHIN 120 NM N OF THE AXIS BETWEEN 32W-41W. SCATTERED SHOWERS/ISOLATED TSTMS ARE W OF 46W WITHIN 180 NM EITHER SIDE OF THE AXIS ENHANCED BY THE TROPICAL WAVE ALONG 52W. ...DISCUSSION... GULF OF MEXICO... QUIET WEATHER CONTINUES ACROSS MUCH OF THE AREA AS A 1017 MB HIGH PRES SYSTEM REMAINS CENTERED IN THE E GULF NEAR 27N86W. IN THE UPPER LEVELS...UPPER TROUGH EXTENDS FROM A SMALL UPPER LOW OVER N MEXICO NEAR 25N98W EWD TO NORTHERN FLORIDA. STRONG SUBSIDENCE AND ASSOCIATED DRY/STABLE AIR ALOFT ACCOMPANIES THE TROUGH DUE TO UPPER LEVEL CONFLUENCE KEEPING SKIES FAIR TO MOSTLY CLEAR ACROSS THE N GULF. BROKEN MID-HIGH LEVEL CLOUDINESS IS STREAMING NEWARD FROM S MEXICO TO S FLORIDA DRIVEN BY A JET STREAM BRANCH ON THE W PERIPHERY OF AN UPPER ANTICYCLONE IN THE CARIBBEAN. WEAK HIGH PRESSURE WILL REMAIN ACROSS THE GULF FOR THE NEXT FEW DAYS...HOWEVER TROPICAL MOISTURE ACROSS THE NW CARIBBEAN WILL PUSH FURTHER NORTH AND BEGIN TO INFLUENCE THE SOUTHERN PORTIONS OF THE GULF LATER TODAY...AND POSSIBLE BECOME MORE WIDESPREAD OVER THE CENTRAL AND EASTERN GULF ON MON/TUES. CARIBBEAN SEA AND ATLANTIC OCEAN W OF 55W... AN UPPER LEVEL TROUGH/RIDGE PATTERN REMAINS IN PLACE ACROSS THIS AREA. THE DEEP-LAYERED TROUGH COVERS THE N GULF AND W ATLC N OF 28N. AT THE SURFACE...THE FRONT HAS WEAKENED TO A TROUGH IN THE DISCUSSION AREA AND EXTENDS FROM 32N58W SWARD TO THE BAHAMAS NEAR 23N75W THEN CONTINUES SSWWARD INTO THE W CARIBBEAN TO NEAR NICARAGUA. BROKEN TO OVERCAST MID/HIGH LEVEL CLOUDINESS ALONG WITH WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 90 NM EITHER SIDE OF THE TROUGH N OF 23N. CLUSTERS OF STRONG TSTMS ARE OVER THE W CARIBBEAN WITHIN 180 NM W OF THE TROUGH AXIS S OF 22N. FARTHER E...A MID/UPPER HIGH IS LOCATED JUST N OF HAITI NEAR 21N72W WITH RIDGING EXTENDING SW TO HONDURAS AND NE TO BEYOND 32N50W. A 60-80 KT SWLY JET STREAM IS RIDING OVER THE THE UPPER ANTICYCLONE AND EXTENDS FROM THE E BAY OF CAMPECHE NORTHEASTWARD T0 S FLORIDA AND CONTINUES NEWARD BEYOND 32N58W. WINDS IN THE RANGE OF 60-80 KT ARE NOTED WITHIN THIS JET MAINLY W OF 65W. STRONG SUBSIDENCE IS ENCOMPASSING MUCH OF THE CARIBBEAN S OF 19N AND CURRENTLY E OF 82W...PUSHING WWARD. TRADEWINDS ARE GENERALLY IN THE 15-20 KT RANGE E OF 80W...LIGHTER WINDS W OF THERE DUE TO THE WEAKNESS IN THE RIDGE. TRADES WILL BECOME MORE UNIFORM AND INCREASE SLIGHTLY AS THE CNTRL ATLC SFC RIDGE EDGES A LITTLE CLOSER. MOISTURE RELATED TO THE SURFACE TROUGH WILL MOVE WWD TOWARDS THE YUCATAN LATER TODAY AND WILL LIKELY AFFECT THE NW CARIBBEAN AND THE W ATLC OVER THE NEXT FEW DAYS. THE LARGE VOLCANIC ASH CLOUDS DETECTED YESTERDAY OVER THE E CARIBBEAN DUE TO AN ERUPTION OF THE MONTSERRAT VOLCANO SAT MORNING IS STILL EVIDENT ON SATELLITE IMAGERY BUT IS BREAKING UP FROM 66W-72W FROM 12N-17N. THE REMAINDER OF ATLANTIC OCEAN... A SHARP UPPER LEVEL TROUGH IS OVER THE CNTRL ATLC WITH THE AXIS EXTENDING THRU 30N44W THROUGH AN UPPER LOW NEAR 21N48W AND INTO THE DEEP TROPICS NEAR 10N54W. THE UPPER LOW IS HELPING TO TRANSPORT UPPER MOISTURE FROM THE DEEP TROPICS NEWARD WITHIN 180 NM TO THE RIGHT OF A LINE ALONG 10N50W 20N44W 28N40W. AN UPPER HIGH IS NEAR 16N32W WITH MID/UPPER LEVEL RIDGING COVERING THE AREA S OF 17N AND E OF 37W. DIFFLUENCE S OF THE RIDGE IS ENHANCING ITCZ CONVECTION. AN UPPER TROUGH IS MOVING SE OVER EXTREME NW AFRICA. THIS TROUGH IS CARRYING MOISTURE FROM THE UPPER TROUGH IN THE CENTRAL ATLC RIDING OVER THE UPPER HIGH INTO W AFRICA. AT THE SFC...A STRONG SPRAWLING 1027 MB HIGH CENTERED NEAR 31N36W COVERS THE ENTIRE REGION SUPPLYING FAIR WEATHER ACROSS A GOOD PORTION OF THE ATLANTIC OCEAN. TRADE WINDS ARE RATHER STRONG ACROSS THE AREA AND WILL LIKELY REMAIN THAT WAY FOR THE NEXT FEW DAYS. $$ CANGIALOSI