000 AXPZ20 KNHC 141004 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC FRI JAN 14 2011 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 0845 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 6N80W 5N92W 7N109W 8N120W 8N130W 8N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF THE AXIS BETWEEN 106W-113W ...AND 120 NM S OF THE AXIS BETWEEN 124W-128W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 135W-138W. ...DISCUSSION... MAIN FEATURE INFLUENCING THE REGION'S WEATHER PATTERN IS AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 32N132W PER WATER VAPOR IMAGERY. AN ASSOCIATED RIDGE AXIS TILTING SEWD EXTENDS FROM THE ANTICYCLONE WELL TO THE NNE TO THE FAR NW CONUS AND WESTERN CANADA. THE ANTICYCLONE SUPPORTS A STRONG SURFACE HIGH OF 1030 MB ANALYZED JUST N OF REGION NEAR 33N130W WITH A RIDGE SE TO 26N124W TO NEAR 21N120W. W OF THE UPPER RIDGE TO THE W OF 140W A DEEP LAYER TROUGH IS NOTED TO THE NE OF THE HAWAIIAN ISLANDS. IT IS SUPPORTING A SURFACE COLD FRONT WITHIN ABOUT 360 NM NW OF THE REGION. WITH THE ANTICYCLONE MOVING SLOWLY EASTWARD AND UPPER LEVEL FLOW BEING SWLY BETWEEN THE FRONT AND 140W...IT IS UNLIKELY IT WILL MAKE A MOVE INTO THE NW SECTION OF THE AREA. AS A MATTER OF FACT...THE UPPER LEVEL ENERGY WITH THE TROUGH WILL CONTINUE TO CHANNEL NEWD UP AND OVER THE RIDGE THROUGH THE NEXT 24 TO 36 HOURS AS THE ANTICYCLONE APPROACHES SOUTHERN CALIFORNIA AND WEAKENS. BY THEN...THE UPPER FLOW BECOMES PRETTY MUCH ALL SWLY ACROSS THE NW CORNER AND NW OF THE REGION AS A RATHER ELONGATED CUT-OFF LOW SETS UP OVER THE FAR WESTERN PORTION OF THE REGION WHILE ENERGY FROM WHAT WAS THE DEEP LAYER HAS EJECTED NE AND E TO THE WESTERN CONUS. A TIGHT PRES GRADIENT ALONG THE SOUTHERN PERIPHERY OF THE RIDGE AS IT INTERACTS WITH A COUPLE OF WEAK SURFACE TROUGHS MOVING WWD THROUGH THE ITCZ ALONG 135W AND 119W IS RESULTING IN AREA OF NE TO E TRADES OF 20-25 KT FROM 8N TO 24N W OF 119W. THIS WAS DEPICTED IN AN ASCAT PASS FROM NEAR 0600 UTC THIS MORNING. SEAS THERE ARE IN THE 8-12 FT RANGE DUE TO NE WINDS AND NW SWELL. ELSEWHERE ANTICYCLONIC SURFACE FLOW CONTINUES TO DOMINATES THE REGION N OF 24N. THE TRADES ARE FORECAST TO DIMINISH IN AREAL COVERAGE OVER THE COURSE OF THE NEXT 24 TO 48 HOURS AS THE HIGH WEAKENS. THE TROUGH WILL CONTINUE ON WWD. THE GFS MODEL IS AGGRESSIVE AS IT HANDLES THE WESTERN MOST TROUGH ALONG 135W DURING THE NEXT LATE FRI NIGHT INTO EARLY SUN MORNING. IT CHURNS UP THE WINDS AND THUS THE SEAS CONSIDERABLY COMPARED TO THE OTHER GLOBAL MODELS. FOR NOW WILL LEAN TOWARDS MODEL CONSENSUS WITH THIS FEATURE...AND NOW GO STRONG WITH THE WINDS AND SEAS FOR HIGH SEAS FORECAST. THE SURFACE TROUGH MENTIONED ABOVE ARE ENHANCING ITCZ CONVECTION AS THEY INTERACT WITH UPPER LEVEL TROUGHINESS TO THE N. OVER THE FAR EASTERN PORTION OF THE REGION A SHORTWAVE TROUGH IS QUICKLY MOVING ESE OVER THE SW U.S. BASIN. AT THE SURFACE...LARGE PRES DIFFERENCES ARE BRINGING NW WINDS OF 20-25 KT THROUGH THE GULF OF CALIFORNIA N OF 23N WITH PROBABLE GUSTS TO 30 KT YESTERDAY AFTERNOON AND EVENING. THESE WINDS WILL SLOWLY DIMINISH TO 20 KT BY 48 HOURS FROM 24N TO 29N. OTHERWISE ...MARINE ISSUES WITH RESPECT TO SEAS IN LARGE SWELLS WILL BE THE MAIN IMPACT OVER MOST OF THE REGION'S WATERS. A STORM CENTER WELL NW OF THE REGION WILL BE THE SWELL GENERATOR FOR SEAS UP 12 FT OVER THE NW SECTION N OF 26N AND W OF 137W. HOWEVER...THE SWELLS WILL GRADUALLY SUBSIDE THROUGH THE NEXT 48 HOURS WITH SEAS DOWN TO 9 FT ALTHOUGH A TIGHT GRADIENT WILL LINGER TO THE N OF 24N BETWEEN 125W-137W ALLOWING FOR N TO NE WINDS OF 20-25 KT AND SEAS OF 8-10 FT. GAP WINDS... STRONG SURFACE RIDGING OVER EASTERN MEXICO AND JUST INLAND THE ISTHMUS OF TEHUANTEPEC IS NOW BRINGING GALE FORCE WINDS OF 35-45 KT THROUGH THE GULF OF TEHUANTEPEC. AN ASCAT PASS JUST PAST 0400 UTC NICELY SHOWED THESE STRONG WINDS REACHING AS FAR S AS ABOUT 13N. SEAS THERE ARE IN THE RANGE OF 12-18 FT. LATEST LOCAL OBSERVATIONS FROM THE STATION IXTEPEC MEXICO ARE SHOWING SUSTAINED WINDS OF 35 KT WITH GUSTS 45 KT AND 50 KT. AS THE GRADIENT SLACKENS OVER THE NEXT 24-48 HOURS THE WINDS WILL RESPOND BY DIMINISHING TO BELOW GALE FORCE. LARGE SWELLS PRODUCING SEAS OF 8-10 FT WILL BE THE MARINE ISSUE AT 24 TO 36 HOURS...THEN SUBSIDE TO 8 FT BY 48 HOURS. STRONG NE WINDS OVER THE WESTERN CARIBBEAN SEA CONTINUE TO FILTER THROUGH THE SOUTHERN CENTRAL AMERICA PASSES WITH DRAINAGE FLOW OCCURRING WITHIN THE VICINITY OF THE GULF OF PAPAGAYO AND NEAR THE GULF OF FONSECA. THE WINDS ARE IN THE RANGE OF 20-25 KT. AS THE WIND DIRECTION MODIFIES SLIGHTLY OVER THE WESTERN CARIBBEAN THROUGH THE PERIOD...WINDS WILL DIMINISH TO BELOW 20 KT WITHIN 18 HOURS IN THE GULF OF FONSECA...AND ARE FORECAST TO CONTINUE AS 20 KT TO WITHIN ABOUT 60 NM OF THE GULF OF PAPAGAYO COAST THROUGH EARLY SATURDAY. $$ AGUIRRE