000 AXPZ20 KNHC 061013 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED JAN 06 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 0915 UTC. ...ITCZ... AXIS ANALYZED ALONG 05N77W TO 06N89W TO 05N100W TO 09N110W...THEN CONTINUED AGAIN FROM 07N114W TO 09N119W TO 07N127W TO 09N132W TO 07N140W. ISOLATED TO SCATTERED MODERATE CONVECTION WAS OCCURRING WITHIN 120 NM OF AXIS BETWEEN 105W AND 127W. ...DISCUSSION... THE VERY PROGRESSIVE WINTER PATTERN OVER THE NORTHERN PORTION OF THE DISCUSSION AREA WILL BECOME RATHER STAGNANT DURING THE NEXT COUPLE OF DAYS AS A REX BLOCK TYPE PATTERN IS DEVELOPING ALONG ABOUT 125W...WITH A SHARPENING UPPER RIDGE N OF 30N AND A BROAD AND SLOWLY E SHIFTING MID TO UPPER TROUGH FROM 25N S TO THE ITCZ ALONG 07N...WITH UPPER LEVEL WLYS S OF 10N. BROAD AND STRONG TROPICAL UPPER RIDGES EXIST ON EACH SIDE OF THIS UPPER TROUGH. A MID TO UPPER LEVEL CYCLONE WAS SHIFTING ESE ACROSS NRN MEXICO...AND GRADUALLY MOVING INTO THE BASE OF A BROAD UPPER TROUGH DOMINATING THE ERN HALF OF N AMERICA. STRONG SWLY FLOW ALOFT IS SHEARING AND ADVECTING ABUNDANT MID TO UPPER LEVEL MOISTURE FROM THE ITCZ E OF 125W...NE ACROSS OLD MEXICO AND INTO THE GULF OF MEXICO...WHERE UPPER LEVEL WINDS ACCELERATE IN EXCESS OF 100 KT E OF 90W. AT THE SURFACE...A NEARLY STATIONARY 1023 MB HIGH PRES WAS N OF THE AREA NEAR 31N127W WITH ITS ASSOCIATED RIDGE DOMINATING MUCH OF THE AREA N OF 18N W OF 115W. THE RIDGE IS BLOCKING THE EASTERN PROGRESSION OF A COLD FRONT THAT EXTENDS FROM 35N134W TO 27N145W. THIS FRONT IS EXPECTED TO DISSIPATE DURING THE NEXT 24 HOURS AND BECOME REINFORCED AND REPLACED BY A SECOND FRONT CURRENTLY APPROACHING FROM THE W OF 150W. LONG PERIOD NWLY SWELL FROM THESE SUCCESSIVE AND FREQUENT FRONTAL BOUNDARIES CONTINUE TO MOVE INTO AND THROUGH THE AREA WATERS...WITH SEAS OF 8 TO 12 FT CURRENTLY ACROSS EXTREME NW PORTIONS OF THE AREA. IN NW SWELL CAN BE FOUND EXTENDING E OF THE FRONT IN THE AREA N OF 23N W OF 135W. AFTER THIS FRONT DISSIPATES...LOOK FOR THE PRES GRADIENT BETWEEN THE AFOREMENTIONED SURFACE RIDGE AND THE NEXT FRONT TO KEEP SLY WINDS AROUND 20 KT OVER NW WATERS FOR THE NEXT FEW DAYS. MEANWHILE...ANOTHER PULSE OF NW SWELL WILL MOVE INTO THE NW WATERS THU AND BUILD SEAS 12 TO 18 FT N OF 20N AND W OF 132W. THE BROAD MID TO UPPER TROUGH ALONG 125W MENTIONED ABOVE EXHIBITS SOME NEGATIVE TILT...AND HAS BEEN COMBINING WITH FRESH NELY FLOW MOVING ACROSS CENTRAL AMERICA TO GENERATE A SERIES OF LLVL PERTURBATION ALONG THE ITCZ...AND GENERALLY S OF 13N. THE MOST RECENT OF THESE ELY WAVES HAS MOVED PAST 121W AND INTO AN AREA OF UPPER CONVERGENCE AND APPEARS TO BE WEAKENING. A NEW ELY WAVE HAS DEVELOPED IN THE PAST 12 HOURS AND WAS ALONG 112W...MOVING W NEAR 15 KT. DUE TO THE SLOW MOVEMENT AND PERSISTENCE OF THE MID TO UPPER TROUGH...THE GFS MODEL RESPONDS BY MAINTAINING A LLVL TROUGH OR ELY WAVE BETWEEN 110W AND 115W DURING THE NEXT 48 HOURS...THEN INDICATES IT BECOMING BETTER ORGANIZED ALONG 110W BY FRI EVENING...IN RESPONSE TO THE UPPER TROUGH MOVING E AND DIGGING. THE OTHER GLOBAL MODELS ARE NOT NEARLY AS AGGRESSIVE IN THIS DEVELOPMENT AND I HAVE THUS DISCOUNTED IT FOR THE SHORT TERM. OTHERWISE...GAP FLOW ACROSS CENTRAL AMERICA CONVERGING ALONG THE N SIDE OF THE ITCZ DOMINATE THE AREA S OF 16N. GAP WINDS... GULF OF TEHUANTEPEC...NLY WINDS HAVE DIMINISHED BELOW STORM FORCE AND WERE SUGGESTED TO REMAIN A STRONG GALE BY A 04 UTC ASCAT PASS...WITH 30 KT NELY WINDS STREAMING DOWNWIND TO ALMOST 98W. PEAK SEAS HERE WERE LIKELY 15-16 FT DUE TO THE RECENT STORM WINDS...WITH A BROAD PLUME EXTENDING S OF 10N. MODELS FORECAST THESE WINDS TO DIMINISH BELOW GALE FORCE THIS AFTERNOON OR EVENING BUT COULD PULSE UP AGAIN AROUND GALE FORCE THROUGH MIDNIGHT BEFORE DROPPING STEADILY AND SHRINKING THROUGH FRI. GULF OF PAPAGAYO...A LARGE PLUME OF NE WINDS 20 TO 30 KT WERE INDICATED BY A 03 UTC ASCAT PASS...WITH THIS PLUME MERGING ALONG THE N SIDE OF THE ITCZ S OF GULF OF TEHUANTEPEC. WINDS EXPECTED TO REMAIN UP AT 20 TO 30 KT THROUGH 24 HOURS BEFORE DIMINISHING. GULF OF PANAMA...A BRIEF NLY PULSE OF 20 TO 25 KT IS EXPECTED BY 24 HOURS THAT WILL DIMINISH 36-48 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ STRIPLING