000 AXPZ20 KNHC 221602 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Apr 22 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 1200 UTC surface analysis and satellite imagery through 1445 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 10N72W TO 07N85W TO 06.5N99W. The ITCZ continues from 06.5N99W TO 07.5N107W TO 04N124W TO 07N134W to beyond 06N140W. Scattered moderate and isolated strong convection is present within 90 nm either side of a line from 10N83W to 06N89W to 05N94W and from 08N to 10N between 136W AND 140W. Isolated moderate and strong convection is present from 08N to 10N between 107W and 117W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Moderate to fresh NW winds with seas of 5 to 7 ft currently prevail across the offshore waters of Baja California as ridging from the NW and lower pressure over the SW United States and NW Mexico combine to maintain a modest pressure gradient over the area. Winds W of the peninsula will gradually diminish through Tue as the high to the NW weakens and lower pressure over the SW United States and NW Mexico fills and shifts east. However, new NW swell moving into the region this morning will help to maintain seas in the 5-7 ft range, expect around 8 ft to the N through W of Isla Guadelupe. Light to gentle variable winds prevail throughout the Gulf of California, and are expected to persist through Tue as the high gradually weakens and the area of low pressure weakens and moves east. Light N winds across the Gulf of Tehuantepec are expected to become light and variable this morning. Another cold front entering the NW Gulf of Mexico today and tonight will induce the next gap wind event over the Gulf of Tehuantepec Mon through Thu. A small plume of N to NE winds will be intermittent across the immediate Gulf waters, and will be strongest during nocturnal drainage flow. Gales are not expected during this event. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh NE to E winds across the region are expected to pulse between nightfall and mid morning to 20-25 kt across and downstream of the Gulf of Papagayo through at least Tue night with seas peaking each episode between 6 and 8 ft. Winds over the Gulf will be lighter on Wed and Thu as high pres N of the Caribbean weakens. Gulf of Panama: Gentle to moderate N to NE winds with seas of 3 to 6 ft in SW swell prevail across the Gulf of Panama and offshore of Panama and Colombia to 250 nm this morning. Active convection continues across the region this morning from 04N TO 09N E of 84W. A surface trough extending W across Panama and Costa Rica, then WSW to 06.5N99W is acting as a focus for the convection. Winds across the Gulf will remain gentle to moderate tonight through Thu, while farther offshore and SW, gentle to moderate SW winds will prevail Sun through Thu. Corresponding seas will generally run between 4 and 6 ft. Elsewhere, mainly light to gentle winds are expected S of 06N through Thu. Cross-equatorial swell will mix with residual swell downwind from Papagayo through Wed, and maintain seas in this area between 5 and 7 ft. Elsewhere seas will subside to 3-5 ft by Sun as long period SW swell from the Southern Hemisphere decay, then rebuild to between 5 and 7 ft on Mon and Tue as another round of SW swell arrive. REMAINDER OF THE AREA... Strong high pressure is centered well offshore of Northern California has begun to weaken and shift NE this morning, as a new cold front approaches from the NW. The high continues to ridge SE across the northern forecast waters to near the Revillagigedo Islands. The pressure gradient between the ITCZ and the high to the north will support fresh to occasionally strong NE trades N of the ITCZ generally between 08N and 22N W of 125W today. The combination of these winds, NW swell and SW swell will support combined seas of 8 to 10 ft over these waters. The area of 8 ft seas is expanding N to near 30N as NW swell propagates into the northern waters. The NW swell will begin to decay below 8 ft tonight before becoming reinforced by another pulse of NW swell by Monday night. There is a brief lull in cross equatorial SW swell and seas have subsided to 8 ft or less near the equator. However, another round of SW swell will cause waters near the equator to build to near 8 ft later today through Tue. The cross-equatorial swell will combine with NW swell to create an even larger area of 7 to 9-foot seas W of 95W along the equator and between 05N and 25N Wed through Fri. $$ Stripling