000 AXPZ20 KNHC 162205 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC FRI JAN 16 2009 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 2145 UTC. ...ITCZ... ITCZ IS CENTERED ALONG 4N78W 4N90W 5N101W 6N110W 8N120W 5N132W 5N140W. SCATTERED MODERATE TO STRONG CONVECTION FROM 7N TO 15N BETWEEN 111W-116W. STRONG MODERATE CONVECTION IS WITHIN 60-120 NM N OF THE AXIS BETWEEN 82W-88W AND 94W-107W. ...DISCUSSION... THE REGION REMAINS IN BETWEEN TWO RATHER LARGE SCALE FEATURES. THE FIRST IS THE TAIL END OF BROAD UPPER LEVEL TROUGHING CENTERED OVER THE MID-WEST REGION OF THE UNITED STATES WHICH REACHES INTO THE FAR EASTERN SECTION OF THE AREA TO N OF ABOUT 27N AND E OF 125W. W OF THE TROUGH...THE AREA IS UNDER MID AND UPPER LEVEL RIDGING PRESENT N OF 24N WITH AN ASSOCIATED ANTICYCLONIC CENTER WELL N OF THE AREA. THE SECOND FEATURE CONTINUES TO BE A RATHER EXTENSIVE LATITUDINAL DEEP LAYER TROUGH STRETCHING ROUGHLY ALONG 135W N OF 15N...THEN SE TO A SMALL MID/UPPER LEVEL CYCLONIC CIRCULATION NEAR 12N128W. THE ASSOCIATED SURFACE COLD FRONT IS JUST NW OF THE AREA...HOWEVER SLY WINDS OF 20 KT PRECEDE THE FRONT AS REPORTED BY A FEW SHIPS OVER THE FAR NW WATERS OF THE AREA. SATELLITE-DERIVED UPPER LEVEL WINDS SHOW QUITE A LARGE AREA OF UPPER LEVEL DIVERGENCE CONTINUING TO ENHANCE SCATTERED MODERATE TO STRONG CONVECTIVE CLUSTERS TO THE E OF THE BASE OF THE TROUGH ALONG AND N OF THE ITCZ AXIS GENERALLY CONFINED FROM 7N TO 15N BETWEEN 111W AND 116W AS MENTIONED IN FIRST PARAGRAPH. EXPECT THIS ACTIVITY TO CONTINUE OVER THE NEXT FEW DAYS AS THE TROUGH SLOWLY TRANSLATES EASTWARD. SOME OF THE GLOBAL MODELS SUGGEST THAT AN EVENTUAL WEAK LOW MAY EVOLVE FROM THIS AREA AND DRIFT NWD OVER THE NEXT 48 HOURS. MODERATE TO STRONG UPPER LEVEL WINDS ARE ALONG AND W OF THE TROUGH AXIS N OF 26N. THESE WINDS CONTINUE TO TRANSPORT UPPER LEVEL MOISTURE IN THE FORM OF HIGH LEVEL CLOUDS N TO WELL N OF THE REGION. THE SURFACE COLD FRONT IS FORECAST TO SLOWLY CLIP THE FAR NW CORNER OF THE AREA IN ABOUT 48 HOURS AS ITS DRIVING UPPER SUPPORT AND RELATED ENERGY PULLS FURTHER AWAY FROM THE AREA TOWARDS THE GENERAL VICINITY OF ALASKA AS GLOBAL MODELS ARE IN PRETTY CLOSE AGREEMENT WITH RESPECT TO THIS SCENARIO. HOWEVER ...THE MAIN ISSUE WITH THIS FRONT AND THE VERY PROGRESSIVE UPPER LATITUDE FRONTAL SYSTEMS THAT FOLLOW BEHIND IT WILL BE LONG PERIOD NW SWELLS GENERATED BY ATTENDANT DEEP LOW PRES SYSTEMS THAT WILL ALSO PASS WELL TO THE N OF 30N OVER THE NEXT FEW DAYS. WAVEWATCH MODEL GUIDANCE IS VERY CONSISTENT IN SHOWING SIGNIFICANT WAVE HEIGHTS OF UP TO 13 FT NOW ENTERING THE FAR NW CORNER OF THE AREA. THESE SEAS WILL POSSIBLY GROW UP TO 18 OR 19 FT SAT INTO SUN WITH SEAS ELSEWHERE RANGING 9-14 FT W OF 130W. WILL HAVE TO MONITOR THIS UPCOMING SWELL EVENT CLOSELY WITH RESPECT TO PROJECTED FORECAST HEIGHTS AND AREAL COVERAGE AS PORTRAYED IN FUTURE MODEL GUIDANCE. ELSEWHERE...BROAD SW TO W UPPER LEVEL COVERS THE AREA SW OF THE BROAD UPPER LEVEL TROUGH OVER THE EASTERN PART OF THE AREA... AND TO THE E OF THE DEEP LAYERED TROUGH OVER TH FARE WESTERN PORTION OF THE AREA. THIS FLOW PATTERN BECOMES CONFLUENT OVER THE FAR EASTERN PART OF THE AREA E OF SOUTHERN BAJA CALIFORNIA AS AN UPPER LEVEL CYCLONIC TAKES SHAPE OVER SOUTHERN CALIFORNIA ...THEN MOVE ESE OVER THE WEEKEND. THE CONFLUENT FLOW ASSOCIATED WITH THE BROAD UPPER LEVEL TROUGH IS RESULTING IN MODERATE TO STRONG SUBSIDENCE INDUCING DRY STABLE AIR OVER MUCH OF THE AREA N OF 24N E OF THE DEEP LAYER TROUGH DESCRIBED IN FIRST PARAGRAPH. BROAD UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA S OF 20N AND TO THE W OF THE TROUGH ALONG 21N119W TO 17N113W TO 8N105W. AT THE SURFACE...HIGH PRES RIDGING SWD OVER THE WESTERN GULF OF MEXICO AND MEXICO MAINTAINS A TIGHT PRES GRADIENT ALONG THE MEXICAN COAST USHERING GALE FORCE WINDS IN THE RANGE OF 35-45 KT INTO THE GULF OF TEHUANTEPEC EARLY THIS EVENING. THESE WINDS ARE FORECAST TO DECREASE SLIGHTLY IN 24 HOURS...THEN A LITTLE MORE IN 48 HOURS AS INDICATED BY THE LATEST 10M AND 30M MODEL WIND GUIDANCE. NE WINDS OF 20-25 KT THROUGH THE GULF OF PAPAGAYO ARE EXPECTED TO CONTINUE OVER THE NEXT 48 HOURS AS STRONG HIGH PRES RIDGING PRESSES SWD OVER CENTRAL AMERICA AND STRONG SW CARIBBEAN TRADES ADVECT WESTWARD ACROSS CENTRAL AMERICA. THESE WINDS MAY ARE EXPECTED TO CHANGE LITTLE OVER THE NEXT 48 HOURS. ELSEWHERE HIGH PRES COVERS THE AREA N OF ABOUT 13N W OF 110W WITH A RIDGE FROM 30N131W TO SW OF THE AREA AT 22N140W. $$ AGUIRRE