000 AXPZ20 KNHC 261523 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE OCT 26 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1400 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM LOW PRES NEAR 10N90W TO 09N96W TO 11N115W TO 08N130W TO 09N140W. SCATTERED MODERATE CONVECTION LIES WITHIN 60 NM S OF THE ITCZ AXIS BETWEEN 92W AND 93W AS WELL AS WITHIN 120 NM EITHER SIDE OF THE ITCZ AXIS W OF 136W. TWO LOW PRES SYSTEMS ARE EMBEDDED IN THE ITCZ W OF 110W. THE LOW PRES SYSTEM NEAR 11N117W HAS SCATTERED MODERATE CONVECTION WITHIN 120 NM SW SEMICIRCLE WHILE THE LOW PRES SYSTEM NEAR 09N122W HAS ISOLATED MODERATE CONVECTION WITHIN 120 NM W QUADRANT. ...DISCUSSION... SUBTROPICS... A STRONG PACIFIC COLD FRONT HAS MOVED THROUGH NE WATERS. GALE CONDITIONS LIE JUST N OF 30N. THERE HAVE NOT BEEN MANY SHIP OBSERVATIONS OFF THE COAST OF THE BAJA N OF 25N OVER THE PAST FEW HOURS...BUT SHIP 3EUS REPORTED 24 KT NW WINDS NEAR 25N113W AND SHIP 3FPR9 REPORTED 29 KT NW WINDS NEAR 29N116W AT 0600 UTC. STRATOCUMULUS CLOUDS FOUND SOUTH OF THE FRONT HAVE BEEN CLEARED N OF THE COLD FRONT. NW SWELLS ARE MOVING THROUGH THE AREA...WITH SIGNIFICANT WAVE HEIGHTS TO 16 FT NEAR 30N120W. THE FRONT IS FORECAST TO DISSIPATE LATER TODAY. THE PRES GRADIENT BETWEEN HIGH PRES BUILDING OFF THE CALIFORNIA COAST BEHIND THE FRONT AND LOWER PRES OVER THE SW U.S. AND NW MEXICO WILL ALLOW 20 KT NW WINDS TO CONTINUE OFFSHORE N OF 28N BETWEEN 117W AND 123W THROUGH TOMORROW MORNING...BUT THE MORE SIGNIFICANT HAZARD WILL BE THE SWELL WHICH WILL REMAIN ABOVE 12 FT IN NE WATERS THROUGH WED NIGHT. A NEW COLD FRONT IS FORECAST TO MOVE INTO NW WATERS WED NIGHT...WITH WINDS TO 20 KT EXPECTED UNTIL THU MORNING BEHIND THE FRONT. SEAS WILL BUILD TO 9 FT BY THU MORNING BEHIND THE WEAKENING COLD FRONT. LARGER NW SWELL WILL MOVE INTO THE FORECAST AREA DURING THE DAY THU. TROPICS... AN UPPER ANTICYCLONE NEAR 18N118W EXTENDS A RIDGE AXIS SW TO 09N129W. MEANWHILE...AN UPPER LOW NEAR 02N127W EXTENDS A TROUGH AXIS NE TO 14N108W. UPPER LEVEL DIFFLUENCE BETWEEN THE TROUGH AND RIDGE AXIS IS ENHANCING CONVECTION NEAR TWO SURFACE LOWS EMBEDDED IN THE ITCZ. THIS CONVECTION IS DETAILED IN THE ITCZ SECTION ABOVE. THE UPPER LOW WILL MIGRATE N TOWARD THE WESTERN SURFACE LOW...BRINGING 30 KT OF SOUTHEASTERLY SHEAR OVER THIS SURFACE LOW WHICH WILL DISSIPATE IT BY WED MORNING. THE EASTERN SURFACE LOW WILL REMAIN UNDER MORE FAVORABLE UPPER LEVEL CONDITIONS AND IS FORECAST TO DRIFT NW OVER THE NEXT TWO DAYS WITH WINDS BUILDING TO 20 KT WITHIN 120 NM OF THE LOW BY TOMORROW MORNING. A WEAK UPPER RIDGE AXIS LIES ALONG 08N W OF 133W. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THIS RIDGE AXIS IS ENHANCING CONVECTION NEAR THE ITCZ OVER WESTERN FORECAST WATERS W OF 136W. CLOSER TO SHORE...A LOW PRES SYSTEM LIES NEAR 10N90W. THE COMPUTER MODELS VARY WITH THE POTENTIAL FOR SOME DEVELOPMENT WITH THIS LOW...BUT THE CONSENSUS SOLUTION KEEPS WINDS DIRECTLY ASSOCIATED WITH THE LOW UNDER 20 KT. THE PRES GRADIENT BETWEEN THIS LOW AND HIGHER PRES TO THE S HAS ALREADY INCREASED SW WINDS TO 20 KT FROM 04N TO 07N BETWEEN 80W AND 93W. SHIP A8OH7 NEAR 05N80W...SHIP WECB NEAR 04N86W...AND SHIP DFCX2 NEAR 06N93W ALL REPORTED SW WINDS BETWEEN 18-20 KT AT 1200 UTC. THIS AREA OF 20 KT WINDS IS FORECAST TO SHIFT NW WITH THE BROAD AREA OF LOW PRES OVER THE NEXT FEW DAYS. $$ SCHAUER