000 AXPZ20 KNHC 130911 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Mar 13 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 0800 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A convergence line extends SW from Panama from 06N85W to 01N95W. Widely scattered to scattered moderate convection is within 180 nm NW of the axis. A weak ITCZ extends from 03N115W to beyond 01N140W. Scattered moderate isolated strong convection is within 90 nm of the axis W of 119W. A southern hemisphere trough-ITCZ is located south of the Equator. Scattered moderate to strong convection is from 01.5S to beyond 03.4S between 84W and 102W, associated with this feature. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING... Another gap wind event for the Gulf of Tehuantepec will begin early this morning, with fresh to strong northerly winds expected near sunrise. Winds will diminish during the day, then re-intensify this evening through Tuesday. High pressure building southward in the Gulf of Mexico behind a cold front will induce strong northerly winds through the Chivela Pass tonight, with latest global model guidance indicating gale conditions to begin Tuesday morning around sunrise, which is 12 hours earlier than previous forecasts. These gales will continue through Tuesday and Tuesday night, peaking at around 40 kt Tue night before slowly diminishing to below gale force Thursday afternoon. High pressure dominating the Gulf of Mexico may induce gale force winds at night beyond Thursday, continuing into the upcoming weekend. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface ridge will extend from NW-SE west of Baja California during the next few days. Moderate NW wind flow will fluctuate under typical daytime and nocturnal processes through Wednesday night. Seas will diminish very slightly today, and reach 3-5 ft tonight through Wednesday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to locally fresh nocturnal NE flow is expected downwind of the gulfs of Papagayo and Panama overnight through the morning hours before diminishing this afternoon. Fresh to strong nocturnal drainage winds are expected again Tuesday and Wednesday nights. A strong surface ridge will build across the Gulf of Mexico and NW Caribbean during the later half of this week, and act to strengthen the gap winds across all the typical gap wind areas Thursday and Friday. Light to gentle winds and combined seas of 4-5 ft are expected elsewhere S of 05N through Wednesday. REMAINDER OF THE AREA... A nearly stationary subtropical high will remain near 32N131W through Tuesday. Fresh to locally strong NE trades will persist across the trade wind belt from 04N to 13N west of 124W for the next 24 hours. Combined seas will be 6-9 ft in mixed swell across the area through this afternoon before both winds and seas subside modestly tonight through late Tuesday. Fresh SW winds and building seas to 9 ft will develop across the waters north of 30N west of 136W Tuesday ahead of a cold front reaching 30N140W Tuesday night. The front will stall on Wednesday, then drift back north of 32N Thursday. $$ Stripling