000 AXPZ20 KNHC 240319 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON MAY 24 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0230 UTC. ...TROPICAL WAVES... TROPICAL WAVE ANALYZED ALONG 121/122W FROM 04N TO 11N WAS MOVING W AT 12 KT AS AVERAGED OVER THE PAST 24 HOURS. THE LOCATION OF THE WAVE AXIS WAS CONFIRMED BY AN 1802 UTC HIGH RESOLUTION ASCAT PASS WHICH INDICATED WELL DEFINED TURNING IN THE ASCAT WIND VECTORS ALONG THE WAVE AXIS. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 09N84W TO 11N90W TO 08N128W TO 07N140W. SCATTERED MODERATE TO STRONG CONVECTION WAS WITHIN 150-180 NM S OF AXIS BETWEEN 85W AND 96W...AND WITHIN 90-120 NM EITHER SIDE OF THE AXIS BETWEEN 96W AND 104W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS WITHIN 90-120 NM EITHER SIDE OF AXIS BETWEEN 125W AND 135W. ...DISCUSSION... A LARGE RIDGE DOMINATES THE EPAC N OF 14N W OF 110W...CENTERED ON A QUASISTATIONARY 1033 MB HIGH PRES CENTER NEAR 34N149W. A TIGHT PRES GRADIENT REMAINS IN PLACE BETWEEN THIS RIDGE AND LOW PRES ACROSS THE INTERMOUNTAIN WEST OF THE U.S. FRESH NW TO N WINDS IN THE 20-25 KT RANGE PER A 1758 UTC ASCAT PASS...HAVE EXPANDED TO COVER THE AREA N OF 20N E OF 123W. THE STRONG PRES GRADIENT OVER NE WATERS WILL BE MAINTAINED THE NEXT FEW DAYS WITH THE MAIN PATTERN CHANGE BEING AN EASTWARD SHIFT IN THE PRES GRADIENT WHICH WILL RESULT IN THE 20-25 KT WINDS TO GRADUALLY CONTRACT E TO WITHIN 240 NM OF THE COAST OF BAJA CALIFORNIA BY 48 HOURS. THE EASTWARD SHIFTING GRADIENT SHOULD ALSO INCREASE THE NW TO N WINDS IN THE GULF OF CALIFORNIA TO 20 KT OVERNIGHT. THESE WINDS SHOULD PERSIST THROUGH 36 TO 48 HOURS AS THEY SLIDE DOWN THE GULF. NE TRADE WINDS BETWEEN THE RIDGE AND THE ITCZ...CURRENTLY IN THE 20-25 KT RANGE ACCORDING TO THE 1800 UTC ASCAT PASS ARE EXPECTED TO SLOWLY SHRINK IN AREAL COVERAGE OVER THE NEXT FEW DAYS AS THE RIDGE WEAKENS. A 60-80 KT SOUTHERN STREAM UPPER JET EXTENDS FROM 17N131W TO 23N120W THEN E ACROSS EXTREME SRN BAJA CALIFORNIA. THE DIFFLUENT RIGHT REAR QUADRANT OF THIS UPPER JET WAS ENHANCING DEEP CONVECTION ALONG THE ITCZ BETWEEN 125W AND 135W EARLIER. THIS CONVECTION HAS WEAKENED OVER THE PAST SEVERAL HOURS. CONVECTIVE DEBRIS FROM THE ITCZ IS BEING TRANSPORTED TO THE NE OVER SRN BAJA CALIFORNIA AND MEXICO BY THIS JET. S OF THIS JET BROAD SW TO WLY FLOW ALOFT DOMINATED MOST OF THE AREA. A BROAD LOW LEVEL CYCLONIC GYRE PERSISTS FROM COLOMBIA W TO ALONG 90W WITH A BROAD LOW TO MID LEVEL CYCLONIC CIRCULATION HAVING DEVELOPED OVER NICARAGUA AND THE ADJACENT PACIFIC WATERS THE PAST 2 DAYS. WIDESPREAD CONVECTION...MUCH OF IT MODERATE TO STRONG...WILL PERSIST ACROSS PORTIONS OF CENTRAL AMERICA FOR THE NEXT COUPLE OF DAYS AS ABUNDANT MOISTURE CONTINUES TO CONVERGE ACROSS THIS AREA IN INCREASING SW LOW LEVEL FLOW OVER THE NEXT FEW DAYS. THIS BROAD LOW IS FORECAST TO DRIFT VERY SLOWLY SW OF THE NEXT FEW DAYS AND WILL CONTINUE TO FORCE ITCZ CONVECTION INTO THE W COASTS OF COSTA RICA AND WRN PANAMA. LARGE CROSS-EQUATORIAL LONG PERIOD SW SWELL CONTINUES TO IMPACT MUCH OF THE PACIFIC COASTLINE WITHIN THE FORECAST AREA. DEEP WATER WAVE HEIGHTS ARE IN THE 8-10 FT RANGE AT 14-17 SECONDS PER WAVEWATCH GUIDANCE. OFFSHORE OF BAJA CALIFORNIA THESE LONG PERIOD SWELL ARE MIXING WITH NW WIND WAVES THAT HAVE DRIVEN SEAS UP TO 13 FT. THE SW SWELLS WILL BEGIN TO FADE BY TONIGHT... REACHING 6-8 FT IN 12-14 SECOND PERIODS BY MON NIGHT. A NEW PULSE OF LONG PERIOD CROSS-EQUATORIAL SWELL WILL MOVE INTO S WATERS MON. $$ COBB