000 AXPZ20 KNHC 030912 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Apr 3 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... The climatological pattern of the ITCZ during the months of March and April typically exhibits dual axes, one N of the Equator and the other one to the S of the Equator as presently observed on the surface analysis. No monsoon trough is currently present E of 140W. Only a trough is analyzed from 08N78W to 07N90W to 05N100W. The Intertropical Convergence Zone continues from 05N100W to 07N120W to 06N130W to 07N140W. A second ITCZ axis is south of the Equator, extending from 06S87W to 02S100W to 04S110W to 05S117. Satellite imagery shows only small and isolated areas of moderate convection with both ITCZ. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge extends SE across the offshore forecast waters through the Revillagigedo Islands producing mainly gentle to moderate NW-N winds, and seas of 3 to 6 ft in open waters. Little change in these marine conditions is expected through Thu. On Fri, moderate to locally fresh NW-N winds and seas in the 5-8 ft range are forecast to affect the waters N of Cabo San Lazaro as the pressure gradient slightly tightens. Gul of California: A recent scatterometer pass showed moderate to fresh southerly winds across the northern waters. Light to gentle winds and modest seas are forecast through the Gulf of California during the next several days, with the exception of gentle to locally moderate winds across the central and south waters on Wed. Gulf of Tehuantepec: Fresh to strong gap winds are possible through the Gulf of Tehuantepec Wed night into Thu as high pressure builds north of the region in the Gulf of Mexico. Currently, marine guidance suggests northerly winds of 20-30 kt and seas in the 6-9 ft range with this event. Climatologically speaking, the final gale force gap wind event occurs in the Gulf of Tehuantepec in late March or early April. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: moderate to fresh NE-E winds are expected early this morning, and then again on Thu, with seas generally in the 4-7 ft range. Gentle to moderate winds will prevail the remainder of the forecast period. Gulf of Panama: gentle to moderate N-NE winds will prevail through Wed, with seas of 4-7 ft in long period SW swell. Light and variable winds are expected thereafter. Elsewhere, light and gentle winds are generally expected, with a better defined southerly wind flow S of 07N/08N by Thu. Seas of 5-7 ft in long period 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 related to 1022 mb high pressure located well N of the area near 41N129W. A new high pressure center is forecast to develop along the ridge axis over the northern forecast waters near 28N126W, and it will remain nearly stationary over the next 48-72 hours. The pressure gradient between the ridge and lower pressures in the vicinity of the ITCZ will result in moderate to locally fresh trade winds and seas to near 8 ft, particularly across the waters from 08N to 16N W of 125W through at least Thu. A new cold front approaching from the west will bring an increase in winds and seas across the far NW waters on 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 again acros the NW corner of the forecast region Thu night into Fri in association with a strong low pressure system crossing N of the area. $$ GR