000 AXPZ20 KNHC 182204 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC MON JAN 18 2010 UPDATED FOR LATEST WIND FORECASTS TO AFFECT GAP WIND AREA AND FOR GULF OF CALIFORNIA TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2130 UTC. ...ITCZ... AXIS IS CENTERED ALONG 3N78W 6N89W 5N100W 7N115W 6N130W 6N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION WAS WITHIN 60 NM S OF THE AXIS BETWEEN 120W-133W. SCATTERED MODERATE CONVECTION WAS WITHIN 30 NM EITHER SIDE OF AXIS BETWEEN 83W-85W...WITHIN 120 NM S OF THE AXIS BETWEEN 116W-120W AND BETWEEN 133W AND 138W. ...DISCUSSION... THE OVERALL BROAD SCALE PATTERN HAS CHANGED VERY LITTLE DURING THE PAST 24 HRS AS VERY STRONG UPPER WESTERLY FLOW CONTINUES ACROSS THE NORTHERN PORTION OF THE AREA N OF ABOUT 25N. A SERIES OF EMBEDDED SHORTWAVE TROUGHS CONTINUE TO RIDE EASTWARD WITHIN THIS UPPER FLOW PATTERN. THE FIST OF THE TROUGHS HAS PUSHED EASTWARD TO EASTERN MEXICO WITH A RESIDUAL AXIS THAT STRETCHED FROM 18N103W SW TO 9N115W ...THEN A SHEAR AXIS SW TO 6N130W TO W OF THE AREA AT 4N140W. A VIGOROUS SHORTWAVE TROUGH EXTENDED FROM JUST OFFSHORE THE CENTRAL CALIFORNIA COAST SE TO 32N123W THEN SW TO 28N127W. A DISSIPATING SURFACE COLD FRONT ASSOCIATED WITH THIS TROUGH EXTENDS INTO THE AREA THROUGH 30N124W AND TO 26N133W. STRONG PRES GRADIENT HAS PRODUCED W TO NW WINDS OF 25 TO 30 KT WITHIN 240 NM W OF THE FRONT N OF 28N AND SW WINDS OF 20 TO 25 KT WITHIN 300 NM E OF FRONT. SEAS UP 21 FT IN NW SWELL WERE NOTED OVER THE FAR NORTHERN WATERS BEHIND THE FRONT. YET ANOTHER SHORTWAVE TROUGH MOVING RAPIDLY EASTWARD WAS NOTED ON WATER VAPOR IMAGERY JUST CROSSING 140W NEAR 32N. A SURFACE COLD FRONT ASSOCIATED WITH THIS TROUGH WAS WITHIN 350 NM NW OF THE AREA WITH A LARGE AREA OF GALE FORCE WINDS PASSING N OF THE 30N AND W OF 137W. GALE FORCE WINDS ARE EXPECTED WITHIN 180 NM AHEAD OF THE THIRD COLD FRONT N OF 29N ONCE IT BRUSHES THROUGH THE NORTHERN WATERS IN ABOUT 42 TO 48 HRS AT WHICH TIME IT IS FORECAST TO EXTEND FROM 30N126W TO NEAR 25N140W. AGAIN BESIDES WINDS REACHING GALE FORCE...THE MAIN ISSUE WITH EACH PASSING FRONT WILL BE LONG PERIOD NW SWELLS PROPAGATING SE INTO THE DISCUSSION AREA OVER THE NEXT FEW DAYS. LATEST WAVEWATCH MODEL GUIDANCE SHOWED SEAS BUILDING UP TO 26 FT IN THESE SWELLS BEHIND THE THIRD FRONT ON WED. NWP MODELS HINT AT MORE GALE WINDS ARRIVING INTO THE NW PORTION OF THE AREA ON WED AS ANOTHER STRONG COLD FRONT MAKES IT INTO THE AREA. ALONG WITH THIS SYSTEM ANOTHER MASSIVE NW SWELL TRAIN IS FORECAST TO SWEEP INTO THE AREA REINFORCING THE PREVIOUS ONES WELL INTO THE END OF THE WEEK. THE DEMARCATION LINE BETWEEN THE PERSISTENT STRONG WESTERLY FLOW AND LIGHTER FLOW TO THE S WAS OBSERVED TO BE A STRONG JETSTREAM BRANCH THAT ENTERED THE AREA AT 32N140W THEN DOVE SE TO 26N127W TO 23N115W WITH MAXIMUM WINDS OF 150-180 KT IN THE JET CORE REGION. TO THE SW OF THIS JET BROAD AND DOMINANT HIGH PRES PREVAILED WITH ITS CENTER LOCATED WELL W OF THE AREA JUST SE OF THE HAWAIIAN ISLANDS. ITS ASSOCIATED RIDGE EXTENDED EASTWARD INTO THE AREA THROUGH 16N140W SE TO 14N131W. WATER VAPOR IMAGERY SHOWED STRONG SUBSIDENCE WITH ASSOCIATED DRY STABLE AIR MASS COVERING THE AREA TO THE N OF THE ITCZ AND W OF 105W. STRONG SUBSIDENCE ALSO WAS PRESENT TO THE SE OF THE FIRST SHORTWAVE TROUGH MENTIONED AND HAD SUPPRESSED ANY DEEP CONVECTION IN THIS AREA...WITH ONLY ISOLATED SHOWERS ALONG THE ITCZ. HOWEVER...DIFFLUENT UPPER LEVEL FLOW NEAR THE SHEAR AXIS WAS ENHANCING CONVECTIVE ACTIVITY ALONG THE ITCZ W OF 118W. A SURFACE TROUGH WAS ANALYZED IN THE DEEP TROPICS WITH ITS AXIS FROM 5N117W TO 12N113W 14N107W. A STATIONARY 1018 MB SURFACE HIGH WAS CENTERED NEAR 24N114W. BROKEN/OVERCAST STRATOCUMULUS CLOUDS ARE N OF 14N W OF 120W TO THE COLD FRONT. NLY WINDS 20 KT WITHIN 90 NM OF THE COAST OF THE GULF OF TEHUANTEPEC ARE EXPECTED TO DECREASE TO BELOW 20 KT BY THIS EVENING. NE TO E WINDS OF 20-25 KT THROUGH THE GULF OF PAPAGAYO MAY BRIEFLY INCREASE TO 30 KT TUE THEN BACK DOWN TO 20 KT WED. NLY WINDS TO 20 KT ACROSS THE GULF OF PANAMA WILL DECREASE TO BELOW 20 KT TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE