000 AXPZ20 KNHC 250315 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT JAN 25 2014 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0300 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC STORM WARNING...AN 1802 UTC OSCAT SCATTEROMETER PASS INDICATED 34-40 KT WINDS. THE FORECAST CALLED FOR WINDS TO CONTINUE TO INCREASE FROM THAT POINT TO AT LEAST 45 KT BY NOW. MODEL GUIDANCE CONTINUES TO PAINT AN AREA OF 45 KT WINDS AT 10M WHILE 30M WINDS ARE GREATER THAN 50 KT. SEA SURFACE TEMPERATURES HAVE BEEN ABLE TO RECOVER SLIGHTLY IN THE IMMEDIATE GULF OF TEHUANTEPEC WATERS SINCE THE PREVIOUS GALE EVENT A COUPLE OF DAYS AGO...WHILE TEMPERATURES MORE DOWNWIND ARE STILL COOLER. THE GALE WARNING HAS BEEN UPGRADED TO A STORM WARNING FOR 00 UTC TONIGHT THROUGH 12 UTC SAT (AN EXTENSION TO 15 UTC MAY BE NEEDED DEPENDING ON OVERNIGHT OBSERVATIONS/TRENDS) WITH THE POSSIBILITY THAT SOME STRONGER WINDS ALOFT MAY BE ABLE TO MIX DOWN TO NEAR THE SURFACE. WINDS ARE THEN FORECAST TO REMAIN AT GALE FORCE THROUGH SAT...DIMINISHING TO 20-30 KT BY 06 UTC SUN...THEN TO 20 KT OR LESS BY SUN AFTERNOON. SIGNIFICANT WAVE HEIGHTS WILL PEAK AT 16-18 FT LATE TONIGHT INTO EARLY SAT... WHILE A LARGE PLUME OF NORTHERLY SWELL WILL CONTINUE TO PROPAGATE TO THE S-SW AWAY FROM THE IMMEDIATE GULF WHILE MIXING WITH LONGER PERIOD NW SWELL. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM 06N77W TO 05N90W. THE ITCZ AXIS EXTENDS FROM 05N90W TO 03N97W TO 08N126W TO BEYOND 07N140W. NO SIGNIFICANT CONVECTION IS NOTED. ...DISCUSSION... A WEAKENING COLD FRONT IS ACROSS THE NW PORTION EXTENDING FROM NEAR 32N136W TO 20N139W...WITH A PRE-FRONTAL TROUGH FROM 24N134W TO 16N139W. ASSOCIATED WINDS OUT AHEAD OF THE FRONT HAVE DIMINISHED TO 20 KT OR LESS WHILE CONVECTION ALSO AHEAD OF THE FRONT HAS BECOME LESS ORGANIZED. THE FRONT IS FORECAST TO GRADUALLY STALL DURING THE NEXT FEW HOURS BEFORE DEGENERATING INTO A REMNANT TROUGH BY EARLY SAT. ANOTHER COLD FRONT CURRENTLY W OF 140W WILL BREACH 30N140W BY MID SAT MORNING WITH ANOTHER ROUND OF FRESH TO STRONG SOUTHERLY WINDS JUST AHEAD OF IT COMMENCING BY LATE TONIGHT INTO EARLY SAT MORNING...THEN LASTING THROUGH MOST OF SUN MEANWHILE...NW SWELL WITH PEAK WAVE PERIODS OF 22-24 SECONDS CONTINUES TO PROPAGATE TO THE SE WITH HEIGHTS OF 8 FT OR GREATER ACROSS THE WATERS W OF 100W. PEAK SIGNIFICANT WAVE HEIGHTS ARE UP TO 16 FT NEAR 25N138W. NEW REINFORCING SETS OF NW SWELL WILL CONTINUE TO FEED INTO THE DISCUSSION WATERS FROM THE W-NW THROUGH AT LEAST THE NEXT 48 HOURS...WITH SEAS OF 8 FT OR GREATER CONTINUING TO COVER THE MAJORITY OF THE WATERS W OF 100W THROUGH SUN. GAP WINDS... GULF OF PAPAGAYO...THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE RIDGING ALONG THE SPINE OF CENTRAL AMERICA AND LOWER PRESSURE ASSOCIATED WITH THE ITCZ AND MONSOON TROUGH WILL CONTINUE TO BRING DIURNAL PULSES OF 20-25 KT NE TO E WINDS OVER AND DOWNWIND FROM PAPAGAYO TO NEAR 90W. WIND-DRIVEN SEAS WILL BUILD UP TO 8- 10 FT DURING THE PEAK WINDS...BRIEFLY SUBSIDING TO AROUND 6-7 FT IN THE IMMEDIATE GULF DURING THE AFTERNOON AND EARLY EVENING HOURS BETWEEN WIND SURGES. GULF OF PANAMA...CURRENTLY THERE IS A BRIEF LULL IN FRESH TO STRONG NORTHERLY WINDS IN THE GULF...BUT WINDS WILL INCREASE BACK TO FRESH TO STRONG LEVELS LATE TONIGHT THROUGH EARLY SAT...DIMINISHING BY SAT EVENING. SEAS WILL PEAK AROUND 8 FT DURING THE STRONGEST WINDS. GULF OF CALIFORNIA...MODEL GUIDANCE INDICATES NORTHERLY WINDS INCREASING TO FRESH LEVELS IN MAINLY THE SOUTHERN HALF OF THE GULF SAT THROUGH SAT NIGHT WITH SEAS LESS THAN 8 FT...AS HIGH PRESSURE RIDGES TO THE S ALONG THE CALIFORNIA COAST WHILE PRONOUNCED TROUGHING DEVELOPS OVER FAR NW MEXICO. $$ LEWITSKY