000 AXPZ20 KNHC 031551 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SUN MAR 03 2013 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS W FROM THE COLOMBIAN COAST AT 04N78W TO 04N110W WHERE LOW LEVEL SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ CONTINUES W TO 04N120W THEN TURNS SW TO BEYOND 01N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FLARING WITHIN 15 NM OF THE COLOMBIAN COAST TO THE S OF 06N...AND IS OBSERVED ALONG THE MONSOON TROUGH WITHIN 150 NM EITHER SIDE OF A LINE FROM 03N90W TO 04N101W...AND ALSO WITHIN 60 NM OF 04N109W. ISOLATED MODERATE CONVECTION IS NOTED FROM 10N TO 15N BETWEEN 94W AND 108W..AND IS POSSIBLE UNDER A DENSE CIRRUS SHIELD OBSERVED WITHIN 180 NM EITHER SIDE OF A LINE FROM 11N140W TO 23N128W. ...DISCUSSION... GAPS WINDS... MINIMAL STORM CONDITIONS IN AND DOWNSTREAM OF THE GULF OF TEHUANTEPEC AT SUNRISE THIS MORNING IS EXPECTED TO WEAKEN TO A STRONG GALE LATE THIS MORNING. THE GRADIENT WILL GRADUALLY RELAX TONIGHT WITH ONE FINAL SURGE AT 30 TO 35 KT IN THE MAXIMUM DRAINAGE FLOW AROUND SUNRISE ON MON...WITH GALE CONDITIONS ENDING BY NOON ON MON. THE N WINDS WILL DIMINISH TO 15 TO 20 KT IN THE GULF OF TEHUANTEPEC ON MON AFTERNOON AND BECOME LIGHT AND VARIABLE BY MON EVENING. THESE LIGHT CONDITIONS WILL LAST THROUGH TUE EVENING...THEN A N SURGE INITIALLY AT 15 T0 20 KT IS EXPECTED AROUND MIDNIGHT TUE NIGHT INCREASING RAPIDLY TO GALE FORCE AT SUNRISE WED. THIS NEXT EVENT WILL LIKELY MAX AT 40 KT ON WED AND DIMINISH BELOW GALE FORCE AROUND MIDDAY ON THU. IN THE MEANTIME...THE SOUTHERN EXTENT OF 25 KT ASSOCIATED WITH THE TEHUANTEPEC EVENT WILL REACH NEAR 08N100W TODAY. A LARGE AREA OF N SWELL WILL PROPAGATE SE...S...AND SW FROM THE GULF OF TEHUANTEPEC AREA. THE NW SWELL COMPONENT IS MERGING ALONG 92W WITH NE SWELL GENERATED BY STRONG NE WINDS NOW BRIDGING THROUGH BOTH THE GULF OF FONSECA AND THE GULF OF PAPAGAYO...GENERALLY AFFECTING ALL THE PACIFIC WATERS TO THE N OF A LINE FROM 09N85W TO 06N92W. THESE STRONG CONDITIONS WILL CONTINUE TONIGHT INCREASING BRIEFLY TO A MINIMAL GALE DOWNSTREAM OF THE GULF OF PAPAGAYO AROUND SUNRISE ON MON. EXPECT THE WINDS TO DIMINISH BELOW 20 KT IN GULF ON FONSECA LATE MON...BUT CONTINUE TO PULSE AT 20 TO 25 KT THROUGH THE GULF OF PAPAGAYO THROUGH LATE THIS WEEK. LONG PERIOD N TO NE SWELLS WILL CROSS THE EQUATOR BETWEEN 90W AND 105W TONIGHT RESULTING SEAS BUILDING TO 10 FT ACROSS THE S PACIFIC WATERS N OF 02S BETWEEN 93W AND 105W ON MON...AND 0SPREADING S TO ALONG 05S BETWEEN 93W AND 113W EARLY TUE. NORTHERLY WINDS AT 15 TO 20 KT ARE CURRENTLY OBSERVED ACROSS THE GULF OF PANAMA TO AS FAR S AS 06N BETWEEN 78W AND 80W. THE GRADIENT WILL INCREASE RESULTING IN 20 TO 25 KT N TO NE WINDS WITHIN 60 NM EITHER SIDE OF A LINE FROM 09N79W TO 03N81W ON MON MORNING...WITH SEAS BUILDING TO 9 FT ACROSS THE WATERS S OF 07N. THESE ENHANCED N WINDS SHOULD DIMINISH BELOW 20 KT ON TUE AFTERNOON. NOTE THAT GUIDANCE HAS BACKED OFF ON THE STRENGTH OF THIS EVENT OVER THE PAST FEW DAYS. A BROAD SURFACE RIDGE DOMINATES THE WATERS N OF THE ITCZ TO THE W OF 110W WITH ANTICYCLONIC SURFACE WINDS AT 15 TO 20 KT ACROSS THE SAME AREA. NE AND NW LONG PERIOD SWELL IS MIXING IN THE AREA RESULTING IN COMBINED SEAS OF 8 TO 10 FT W OF LINE FROM 30N115W TO 04N128W. LITTLE CHANGE EXPECTED TONIGHT THEN A WEAK COLD FRONT...ACCOMPANIED BY ONLY A 5 TO 10 KT SW-W-NW WIND SHIFT... WILL SWEEP E ACROSS THE WATERS TO THE N OF 27N. THE POST FRONTAL NW FLOW WILL ONLY INCREASE TO 15 TO 20 KT...BUT ADVECT A NEW BATCH OF LONG PERIOD NW SWELL INTO THE NW WATERS DRIVING COMBINED SEA HEIGHTS UP TO 13 FT ALONG 29N EARLY TUE...WITH THESE SEAS SHIFTING E ON WED...AND SUBSIDING BELOW 12 FT ON WED NIGHT. $$ NELSON