000 AXPZ20 KNHC 040930 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Apr 4 2018 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough reaches from 09N84W to 03N97W to 03N105W, then the ITCZ from 03N105W to 06N140W. Scattered moderate convection is from 06N to 09N between 126W and 137W. A Southern Hemisphere ITCZ is south of 02S between 95W and 108W, with no significant convection noted. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak ridge extends SE across the offshore forecast waters into the Revillagigedo Islands, maintaining mainly gentle to moderate NW winds, and seas of 4-6 ft. Little change in marine conditions is expected into Thu morning. An mid-upper level disturbance will shift eastward across the region on Thu, bringing moderate to locally fresh NW-N winds and 5-7 ft seas mainly in the waters N of Cabo San Lazaro as ridging builds behind the disturbance. Farther south, a weak pressure pattern supporting generally light winds will transition later in the week as high pressure builds north of the region. This will support fresh to strong gap winds in the Gulf of Tehuantepec late Wed night into Thu morning. Marine guidance suggests northerly winds of 20-30 kt and seas in the 6-8 ft range during this brief event. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate NE to E gap winds and 3-5 ft seas will increase to fresh winds and 4-7 ft seas on Thu as high pressure builds north of the region. Gentle to moderate winds will prevail during the remainder of the forecast period. Gulf of Panama: gentle to moderate N-NE winds will prevail today, with 4-5 ft seas in SW swell. Light and variable winds are expected thereafter. Elsewhere, light and gentle winds are generally expected, with better defined southerly winds developing S of 07N by Thu. Seas of 5-7 ft in SW swell will subside to 3-5 ft Wed through Fri. REMAINDER OF THE AREA... A broad ridge dominates the forecast region north of 15N and W of 110W associated with high pressure located N of the area near 31N127W. The high is expected to remain nearly stationary during the next 48 hours. The gradient between the ridge and lower pressures in the vicinity of the ITCZ will produce moderate to locally fresh trade winds and seas to near 8 ft, particularly across the waters from 08N to 15N W of 125W later this week. A cold front approaching 140W will bring an increase in winds and seas across the far NW waters Wed. Expect fresh to strong southerly winds and seas of 8-9 ft ahead of the front and NW of a line from 30N136W to 27N140W by late Wed. Winds will increase mainly in NW waters Thu night and Fri as a strong low pressure system passes N of the area. $$ Mundell