000 AXPZ20 KNHC 170356 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon May 17 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 0345 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northern Colombia to 09N79W to 08N90W to 10N110W and to 10N126W, where latest scatterometer data indicates that it transitions to the ITCZ to 06N132W and to beyond 06N140W. Scattered moderate to isolated strong convection is within 120 nm south of the trough between 86W-88W, also within 90 nm north of the trough between 101W-103W and between 105W- 107W. Scattered moderate convection is within 120 nm south of the trough between 78W-80W, also between 100W-103W and between 104W-107W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore forecast waters of Baja California producing mainly moderate to locally fresh NW to N winds. A small area of fresh to strong W-NW winds is noted near Cabo San Lucas based on a scatterometer pass. Fresh to locally strong winds are expected N of Cabo San Lazaro Mon evening into Tue as the pressure gradient tightens some. Seas will build to 5-7 ft. Winds will further increase to fresh to strong speeds mainly west of central and northern Baja California beginning late Thu as stronger high pressure builds southeastward across the waters west of Baja California. Northwest swell will build seas as it propagates across the waters north of Punta Eugenia Tue night into Wed. Gulf of California: Winds will briefly increase to 20-25 kt across the northern part of the Gulf tonight with seas building to 4-6 ft. then, moderate to fresh southeast winds and seas in the 4-6 ft range will prevail across the northern Gulf Wed through Thu night. Elsewhere, gentle to moderate southerly winds are expected through Tue. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... The earlier fresh to strong northeast to east winds across the Papagayo region have become east to southeast winds of mainly fresh speeds along with seas of 5-7 ft. These winds will change little through Mon. Long-period cross equatorial southerly swell will continue to impact the offshore forecast waters over the next several days. Seas will build to 8 ft between Ecuador and the Galapagos Islands tonight into Mon, then subside to less than 8 ft by Mon night. Additional pulses of long-period SW swell will reach the area by Wed building seas to 8 ft or higher. REMAINDER OF THE AREA... A rather broad surface ridge is the main feature over the northern forecast waters. It is anchored by a 1028 mb high center that is located north of the area near 38N141W. The pressure gradient between the high pressure and lower pressures in the vicinity of the ITCZ is allowing for mainly moderate to locally fresh trade winds from 11N to 19N between 115W-136W, with peak seas of 8 ft. Gentle to moderate trade winds are noted elsewhere, with seas in the range of 6-7 ft mainly due to a southerly swell component. Long-period cross equatorial southerly swell will also impact the waters south of 10N and east of about 111W, except in the lee of the Galapagos Islands by Mon morning. A trough is located in the deep tropics along a position from 13N129W to 07N130W. Scattered showers and isolated thunderstorms are noted from 10N to 15N between 127W-132W. Similar activity is to its east from 06N to 13N between 121W-127W. Another trough is analyzed from 07N137W to 03N140W. Scattered showers and thunderstorms are seen east of this trough from 05N to 08N between 133W-135W. Scattered showers and isolated thunderstorms exist from 05N to 07N between 135W-140W. The first trough is forecast to move west of 140W late Tue and dissipate. The second trough is forecast to cross 140W early on Mon. $$ Aguirre