000 AXPZ20 KNHC 190933 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED MAY 19 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0700 UTC. ...TROPICAL WAVES... TROPICAL WAVE ALONG 79W N OF 02N IS MOVING W INTO THE PACIFIC AT 10-15 KT. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 150 NM E OF THE WAVE N OF 03N AS WELL AS WITHIN 150 NM EITHER SIDE OF THE ITCZ BETWEEN THE WAVE AND 84W. SATELLITE PRECIPITABLE WATER IMAGERY SHOWS A POOL MOSITURE NEAR THE WAVE WITH VALUES EXCEEDING 2.5 INCHES. THE WAVE LIES ON THE SE SIDE OF AN UPPER ANTICYCLONE AND CONDITIONS ALOFT ARE EXPECTED TO BECOME MORE DIFFLUENT OVER THE NEXT DAY OR SO. CONDITIONS ARE FAVORABLE FOR DEEP CONVECTION TO CONTINUE NEAR THIS WAVE OVER THE NEXT DAY OR TWO. TROPICAL WAVE FROM 13N96W TO 03N98W IS MOVING W AT 15 KT. THIS WAVE IS ASSOCIATED WITH A WELL DEFINED MID LEVEL CIRCULATION AND IT CURRENTLY HAS SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WITHIN 330 NM W OF THE WAVE FROM 05N TO 11N. THIS WAVE LIES ON THE EDGE OF A RIDGE ALOFT THAT EXTENDS SW TO AN ANTICYCLONE NEAR 10S100W. CONDITIONS WILL REMAIN DIFFLUENT ALOFT NEAR THE WAVE THROUGH WED WITH NE SHEAR INCREASING THU. THE INCREASED SHEAR IS EXPECTED TO REDUCE THE CONVECTION NEAR THE SYSTEM. TROPICAL WAVE FROM 13N123W TO 04N126W IS MOVING W AT 10 TO 15 KT. THERE IS LITTLE CONVECTION ASSOCIATED WITH THE WAVE AS IT LIES UNDER 20 KT OF SW SHEAR N OF 07N. SATELLITE PRECIPITABLE WATER IMAGERY SHOWS THE AREA NEAR THE LOW HAS BECOME DRIER OVER THE PAST 6-12 HOURS. NO SIGNIFICANT CHANGE IN CONVECTION IS EXPECTED WITH THIS WAVE OVER THE NEXT FEW DAYS. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 07N80W TO 08N89W TO 10N113W TO 07N130W TO 06N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS WITHIN 150 NM EITHER SIDE OF THE ITCZ AXIS E OF 84W. SCATTERED MODERATE CONVECTION IS WITHIN 150 NM N OF THE ITCZ AXIS BETWEEN 108W AND 112W...WITHIN 120 NM N OF THE ITCZ AXIS BETWEEN 116W AND 119W...AND WITHIN 120 NM S OF THE ITCZ AXIS BETWEEN 121W AND 123W. ...DISCUSSION... MEAN FLOW ALOFT HAS TURNED MORE ZONAL OVER THE LAST 24 HOURS. THIS ZONAL FLOW IS QUICK TO CARRY THE NEXT SYSTEM EASTWARD FROM THE CENTRAL PACIFIC...WITH ITS COLD FRONT EXPECTED TO GRAZE NW WATERS OVERNIGHT WED NIGHT AS IT WEAKENS. THIS COLD FRONT IS SHOVING THE DOWNSTREAM RIDGE TOWARD THE COAST. THE TIGHTENING PRES GRADIENT BETWEEN THIS RIDGE AND TROUGHING OVER THE SOUTHERN PLAINS AND NE MEXICO HAS ALLOWED NW TO N WINDS TO INCREASE ALONG THE W COAST OF BAJA CALIFORNIA. THE ASCAT PASS FROM 0514 UTC SHOWS 20 TO 25 KT NW TO N WINDS WITHIN 180 NM OF THE W COAST OF BAJA CALIFORNIA. RIDGING WILL BUILD FURTHER BEHIND THE COLD FRONT WITH A 1032 MB HIGH EXPECTED TO SET UP SHOP NEAR 34N144W LATE THU. THIS WILL CAUSE THE AREA OF BAJA WINDS TO EXPAND W AND WILL BUILD SEAS TO 10 FT ALONG 30N BY 48 HOURS. ALSO...LOOK FOR NE TRADE WINDS TO EXPAND N OVER THE NEXT FEW DAYS AS A RESULT OF THE INCREASED PRES GRADIENT BETWEEN THE BUILDING SUBTROPICAL HIGH AND THE ITCZ TO THE S. AN UPPER LEVEL ANTICYCLONE IS CENTERED NEAR 14N96W WITH A BROAD RIDGE AXIS EXTENDING SE THROUGH THE NW COAST OF COSTA RICA INTO NE COLOMBIA. STRONG CONVECTION DESCRIBED IN THE TROPICAL WAVE SECTION LIES S OF THIS RIDGE AXIS NEAR THE COASTS OF COSTA RICA...PANAMA...AND WESTERN COLOMBIA. THE RIDGE ALSO EXTENDS SW OF THE ANTICYCLONE CENTER TOWARD 07N137W. MEANWHILE...A 50-70 KT W-SW UPPER JET PARALLELS THE RIDGE AXIS WITH ITS JET CORE APPROXIMATELY 510 NM N OF THE RIDGE. THE JET IS TRANSPORTING CONVECTIVE DEBRIS FROM THE ITCZ NORTHEASTWARD INTO CENTRAL MEXICO. CROSS-EQUATORIAL LONG PERIOD SW SWELL WILL REACH MUCH OF THE PACIFIC COASTLINE WITHIN THE FORECAST AREA TODAY WITH WAVE HEIGHTS IN THE 4-6 FT RANGE NEAR THE COAST. HOWEVER...THE HIGHEST ENERGY WAVE FIELD...WITH SWELL UP TO 20 SECONDS AND SIGNIFICANT WAVE HEIGHTS TO 9 FT...IS CURRENTLY PROPAGATING INTO SOUTHERN WATERS PRIMARILY BETWEEN 93W AND 130W. THIS WAVE TRAIN WILL MOVE NE TOWARD THE MEXICAN AND CENTRAL AMERICAN COAST THROUGH 48 HOURS AND WILL INCREASE WAVES TO 10 FT IN 20 SECOND SWELL IN THE COASTAL WATERS AND ON THE BEACHES FRI AND INTO THE WEEKEND. $$ SCHAUER