000 AXPZ20 KNHC 150220 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0215 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING WARNING WARNING WARNING... The most recent scatterometer pass provided observations of gale force winds across the Gulf of Tehuantepec while an altimeter pass indicated seas to 11 ft. Fresh to strong northerly winds extend downwind of the Gulf to near 13N96W. Winds will further increase to near 40 kt tonight with seas building to 13-14 ft. The winds may briefly diminish to 30-35 kt Wednesday afternoon and evening, but will increase again to 40 kt Wednesday night 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 09N to 13N between 94W and 100W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough axis extends from 06N85W to 02N92W. The intertropical convergence zone axis extends from 05N113W to 06N121W to 03N130W to 02N140W. Isolated moderate convection is within 90 nm north of the ITCZ axis between 113W and 122W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section for information on the Gulf of Tehuantepec gale warning. A 1020 mb high pressure located near 31N129W extends a ridge across the offshore forecast waters west of Baja California to beyond the Revillagigedo Islands. Gentle to locally moderate winds and seas generally under 5 ft are noted under the influence of the ridge. Gentle and variable winds and seas of 2 ft or less are inside the Gulf of California. These marine conditions will persist 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 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. Fresh to strong northerly winds are also forecast across the Gulf of Panama and downwind to about 4N-5N at night begining Wednesday night. Seas will build to 6-7 ft in this area, including offshore of the Azuero Peninsula. These weather conditions will likely persist through early Friday morning. 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 1020 mb surface high centered near 31N129W 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 Wednesday 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 set 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 4-7 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. $$ GR