000 AXPZ20 KNHC 120256 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC FRI FEB 12 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0130 UTC. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED ALONG THE LINE 03N77W TO 05N100W TO 12N112W TO 05N129W TO 02N140W. SCATTERED MODERATE CONVECTION LIES WITHIN 270 NM N OF AXIS BETWEEN 107W AND 111W. A TROUGH IS EMBEDDED IN THE ITCZ FROM 15N112W TO 08N118W AND SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 180 NM E OF TROUGH FROM 08N TO 11N. ...DISCUSSION... A HIGHLY AMPLIFIED MID TO UPPER LEVEL PATTERN DOMINATES THE FORECAST AREA...WITH AN UPPER RIDGE FROM THE EQUATOR AT 105W EXTENDING NE TO THE GUATEMALA COAST SEPARATING SHARP TROUGHING ALONG 90W FROM A POSITIVELY TILTED MEAN TROUGH FROM WESTERN TEXAS SW TO NEAR 20N118W AND THEN S TO THE EQUATOR NEAR 125W. THE NORTHERN PORTION OF THIS TROUGH STEMS FROM AN UPPER LOW THAT PASSED ALONG THE MEXICO/ARIZONA BORDER S OF PHOENIX YESTERDAY AFTERNOON AND IS NOW BEGINNING TO PHASE WITH A NORTHERN STREAM TROUGH E OF THE ROCKY MOUNTAINS. IN TURN...THIS PORTION OF THE MEAN TROUGH IS MOVING AWAY FROM THE AMPLIFIED PORTION OVER THE PACIFIC. A SURFACE REFLECTION OF THIS STRONG MID TO UPPER TROUGHING IS EMBEDDED IN THE ITCZ FROM 15N112W TO 08N118W. SCATTERED MODERATE CONVECTION CURRENTLY LIES WITHIN 180 NM E OF THIS TROUGH FROM 08N TO 11N. THIS CONVECTION LIES WITHIN THE DIFFLUENT REGION IN THE REAR RIGHT QUADRANT OF THE UPPER JET AND BETWEEN THE MEAN TROUGHING THAT EXTENDS NORTHWARD AND THE UPPER RIDGE TO THE E. THIS MEAN TROUGH WILL DECOUPLE OVER THE NEXT TWO DAYS...WITH THE NORTHERN PORTION PASSING E THROUGH THE SOUTHEASTERN U.S...CARRYING THE STRONG UPPER JET WITH IT ON ITS LEADING EDGE AND LEAVING THE ENERGY OVER PACIFIC WATERS BEHIND. IN TURN...THE VERTICAL LIFT IN THE ATMOSPHERE ASSOCIATED WITH THE UPPER JET WILL DIMINISH ALONG WITH WILL THE CONVECTION. A 1024 MB HIGH PRES CENTER NEAR 30N124W IS PRODUCING A TIGHT PRES GRADIENT BETWEEN IT AND LOWER PRES ASSOCIATED WITH THE ITCZ AND THE AFOREMENTIONED TROUGH EMBEDDED IN IT...RESULTING IN A VERY BROAD ZONE OF FRESH TO STRONG NE TRADES FROM 05N TO 21N W OF 110W. THE ASCAT PASSES FROM 1752 AND 1932 UTC ALSO REVEALED STRONG SURFACE CONVERGENCE NEAR A SECOND TROUGH FROM 15N127W TO 09N132W. ASCAT CAPTURED 30 KT N TO NE WINDS ON THE WEST SIDE OF EACH OF THESE SURFACE TROUGHS. THESE WINDS WILL GRADUALLY DIMINISH DURING THE NEXT 48 HOURS AS THE TROUGHING ALOFT DECOUPLES AND WEAKENS...WEAKENING THE SURFACE TROUGHING. A TIGHT PRES GRADIENT BETWEEN THE SURFACE RIDGE EXTENDING SE ALONG THE MEXICAN COAST FROM THE HIGH NEAR 30N124W TO 15N97W AND THE TROUGH OF LOW PRES OVER EASTERN MEXICO AND THE WESTERN GULF OF MEXICO ASSOCIATED WITH THE PREVIOUSLY DISCUSSED UPPER TROUGH HAS BROUGHT 20 KT NORTHERLY WINDS TO THE GULF OF CALIFORNIA BETWEEN 23N AND 29N. THE PRES GRADIENT WILL REMAIN TIGHT HERE THROUGH SAT NIGHT AS HIGH PRES MOVES INTO EASTERN MEXICO AND THE NW GULF OF MEXICO BEHIND THE FRONT WHILE LOW PRES BUILDS ALONG THE WESTERN SLOPES OF THE SIERRA MADRE OCCIDENTAL. 20 KT WINDS ARE EXPECTED TO CONTINUE IN THE GULF OF CALIFORNIA FOR THE NEXT 48 HOURS...BUT WILL SHIFT TO THE NORTHERN HALF SAT. ELSEWHERE...A WEAK COLD FRONT HAS MOVED INTO NW WATERS. WINDS ASSOCIATED WITH THE FRONT HAVE DIMINISHED BELOW 20 KT. LONG PERIOD NW SWELL IS MOVING AHEAD OF FRONT WITH SIGNIFICANT WAVE HEIGHTS ALREADY TO 16 FT NW OF THE FRONT. BASED ON THE 4 FT SIGNIFICANT WAVE HEIGHT OBSERVATION FROM ZCDA9 NEAR 28N132W AT 0000 UTC AND THE 2000 UTC JASON1 PASS...SLOWED THE WAVEWATCH SE PROGRESS OF THIS SWELL BY APPROXIMATELY 60 NM TO 75 NM. THE LEADING EDGE OF THIS NW SWELL WILL CONTINUE SE WHILE A NEW SURGE OF NW SWELL MOVES INTO NW WATERS FRI AFTERNOON AND RAISES WAVE HEIGHTS TO 20 FT BY EVENING. ANOTHER COLD FRONT WILL APPROACH NW WATERS SAT EVENING WITH WINDS EXPECTED TO REACH 20 KT IN THE SW FLOW AHEAD OF THE FRONT JUST AFTER 0000 UTC SUN. GAP WINDS... THE COLD FRONT DEVELOPING IN THE NW GULF ASSOCIATED WITH THE UPPER TROUGH OVER THE SOUTHERN PLAINS AND NORTHERN MEXICO WILL BRING GALE FORCE WINDS TO THE GULF OF TEHUANTEPEC BY TOMORROW EVENING THAT WILL REACH JUST BELOW STORM FORCE EARLY SAT MORNING BEFORE DIMINISHING TO A MINIMAL GALE SAT EVENING. STRONG CARIBBEAN TRADES ALONG THE NW COAST OF COLOMBIA HAVE ENHANCED NORTHERLY FLOW INTO GULF OF PANAMA WITH 20 TO 25 KT WINDS CURRENTLY IN PLACE. WINDS WILL DIMINISH BELOW 20 KT HERE BY FRI AFTERNOON AS THE COLD FRONT DEVELOPING IN THE GULF OF MEXICO QUICKLY PASSES SE INTO THE NW CARIBBEAN...WEAKENING THE PRES GRADIENT BETWEEN THE CLIMATOLOGICAL LOW PRES OVER COLOMBIA AND HIGH PRES TO ITS N. THE 1612 UTC ASCAT PASS SHOWED 20 TO 25 KT WELL DOWNWIND OF THE GULF OF PAPAGAYO. SHIP ZCDF4 PASSING THROUGH THE GULF BETWEEN 0000 AND 0100 UTC INDICATED 10-METER WINDS WERE NEARLY TO GALE FORCE CLOSE TO THE COAST. THESE WINDS WILL CONTINUE OVERNIGHT AND THEN QUICKLY DIMINISH FRI AS THE PRES GRADIENT OVER THE WESTERN CARIBBEAN AND CENTRAL AMERICA WEAKENS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ SCHAUER