000 AXPZ20 KNHC 151002 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Mar 14 2017 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING Gale force winds continue to spill across the Gulf of Tehuantepec and spread downwind towards the south and southwest this morning. Recent scatterometer passes from 0300 to 0400 UTC showed gales around 35 kt extending from the coast to near 14.5N95W while strong NE winds then spread farther SW to near 11.5N98W. Seas across this area are assumed to be in the 9 to 14 ft range. The peak winds are expected to increase slightly to near 40 kt before sunrise and then diminish during the afternoon and early evening hours to 30-35 kt. Peak wind should increase again to near 40 kt late tonight through Thursday night. Minimal gale force winds will then persist into the weekend with peak winds expected during late night and early morning hours. Northerly swell generated by this gap wind event will propagate southward and mix with long-period southwest swell from the southern hemisphere, resulting in combined seas of 8 ft or greater covering the waters from 08N to 13N between 95W and 102W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from near 08N86W TO 02N94.5W. A second trough meandering south of the equator enters the region near 03.4S96W TO 03S100W TO 01S112W. The ITCZ extends 05N115W TO 06.5N127W TO beyond 03N140W. Scattered moderate isolated strong convection is within 150 nm of trough between 84W AND 93W. Scattered moderate isolated strong convection is S of 00N between 87W AND 109W. Scattered moderate to strong convection is within 150 nm N of the ITCZ between 115W AND 132W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section for information on the Gulf of Tehuantepec gale warning. A 1022 mb high pressure center is located near 32N128W and extends a ridge SE across the offshore forecast waters west of Baja California to offshore of Manzanillo, Mexico near 16.5N105W. Gentle to locally moderate NW winds and seas generally under 5 ft are noted across these waters under the influence of the ridge. Gentle and variable winds and seas of 2 ft or less are inside the Gulf of California. These general marine conditions will persist through the rest of the work week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE-E winds are expected across and downwind of the Gulf of Papagayo, particularly during the overnight and early morning hours through the remainder of the week and into the upcoming weekend. Seas will build to 8-9 ft during the strongest winds. Winds could briefly reach 25-30 kt early Thursday morning before diminishing to 20-25 kt during the day. Look for building high pressure across the NW Caribbean and Gulf of Mexico to induce strong NE gap winds from Papagayo to the Gulf of Fonseca Thursday night and Friday. Fresh to strong northerly winds are also forecast across the Gulf of Panama and downwind to about 4N-5N at night beginning tonight. Seas will build to 5-7 ft in this area, including offshore of the Azuero Peninsula. These weather conditions will likely persist through early Friday afternoon. Otherwise, light to gentle winds and combined seas of 3-5 ft are expected to continue through the week and into the upcoming weekend. REMAINDER OF THE AREA... A 1022 mb surface high centered near 32N128W will remain nearly stationary over the next 24 hour. A cold front is forecast to briefly clip the far NW corner of the area by this afternoon, then lift north as another cold front approaches from the west. Fresh to strong southerly flow is expected ahead of the second front Thursday night into Friday, with the front entering the forecast region Friday afternoon. This front will reach from 30N134W to beyond 25N140W Friday night, and from 30N131W to 24N140W on Saturday while weakening. A pulse of large northwest swell will arrive behind the front for the end of the week into the upcoming weekend building seas up to 11 ft. Otherwise, mainly moderate to locally fresh trades will persist elsewhere across the open tropical Pacific waters. Combined seas will be in the 5-7 ft range, but will build along and south of 10N Saturday and Saturday night as fresh swells generated by central American gap wind events propagate westward. $$ Stripling