000 AXPZ20 KNHC 031519 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1519 UTC Mon Jun 3 2019 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 1500 UTC. ...SPECIAL FEATURES... Showers and thunderstorms persist across southeastern Mexico in association with a broad area of low pressure over the Bay of Campeche. This system will likely continue producing heavy rainfall over southern Mexico and northern Guatemala over the next couple of days with sufficient environmental instability and deep moisture streaming northward from the eastern Pacific. Please refer to your local meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends across Central America and southern Mexico, entering the Pacific at 16N94W and continuing to 07N107W to 10N120W. The ITCZ continues from 10N120W to beyond 07N140W. Scattered moderate convection is noted north of 10N between 85W and 90W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Ship observations and an earlier scatterometer satellite pass indicated gentle to moderate NW winds for the most part off Baja California along with light to gentle breezes over most of the Gulf of California. The mild conditions are ongoing between high pressure west of the are and a 1006 mb low centered over the northern Gulf of California. The overnight scatterometer satellite pass also indicated locally higher fresh to strong NW winds south of Cabo San Lucas, and fresh SW winds over the northern Gulf of California near 30N. These stronger winds are related to overnight drainage flow, and are fairly short lived. Farther south, a weak pressure pattern is maintaining light to gentle breezes. A few overnight drainage related thunderstorms were active off the Mexican coast off from western Oaxaca through the coast of Guerrero. Long period SW swell persist across the open waters supporting 4 to 6 ft seas. The ridge will weaken through Tue as a weak trough moves across Baja California Norte and the northern Gulf of California, allowing moderate to fresh southerly winds over the far northern Gulf of California late Wed. The trough is related to a deep layer cut off low pressure area migrating across the southwestern United States. Farther south, weak low pressure will remain nearly stationary off the coast of southern Mexico through late Tue along the monsoon trough. Northerly swell will reach the waters off Baja California Norte by late week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle W to SW winds persist over the Central American offshore waters south of the monsoon trough with seas generally ranging from 4-7 ft in SW swell. Long period SW swell over the southern waters between Ecuador and the Galapagos Islands is likely producing seas to 8 ft. Seas will briefly subside Tue night through Wed before another long period SW swell event results in 8 ft seas by late week. REMAINDER OF THE AREA... A ridge extends southeastward from 1025 mb high pressure near 35N140W to the Revillagigedo Islands. An overnight altimeter pass revealed a small area of seas to 8 ft in northerly swell north of 29N between 125W and 130W. Moderate to locally fresh NE trade winds prevail between the ridge and the ITCZ. Trade winds will diminish slightly over the next couple days as the ridge weakens over the high seas. By Fri, stronger high pressure will build into the area from the NW. The resulting pressure gradient will result in fresh N to NE winds over the waters north of 26N with combined seas building to 8-10 ft. Farther south, overnight altimeter data still indicated wave heights to 8 ft south of the Equator generally west of 100W. Residual swell will decay from west to east through Tue. Another SW swell event will impact the far southern waters mid to late week with seas once again peaking to 8 ft south of the Equator. $$ Christensen