NHC Tropical Weather Discussion (East Pacific) National Hurricane Center - Tropical Weather Discussion (East Pacific)

  • NHC East Pacific Tropical Weather Discussion

    000 AXPZ20 KNHC 221531 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1257 UTC Wed May 22 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Costa Rica near 10N85W to a 1008 mb low pressure near 11N88W to 11.5N95W to 09N107W to 05N125W. The ITCZ then continues along 05N125W to beyond 05N140W. Moderate to strong convection within 120 nm SE semicircle of low center. Scattered moderate isolated strong convection from 08N to 12N between 95W and 105W. Similar convection is also noted from 05N to 08N between 100W and 106W, and from 05N to 11N between 107W and 115W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge, anchored by a 1031 mb high pressure located N of area near 41N138W, dominates the offshore forecast waters W of Baja California. The pressure gradient between the ridge and lower pressure across the SW United States and NW Mexico supports fresh to strong NW winds N of 28N E of 125W with seas up to 11 ft in NW swell. Winds are forecast to diminish in about 24 hours, however seas will continue to build up to 13 ft N of Punta Eugenia by Thu morning. Seas greater than 8 ft in NW swell will continue to affect the area through Fri night. Gulf of California: The same pressure gradient between the ridge west of Baja California and lower pressure across the SW United States supports strong SW to W winds in the northern Gulf of California. The tail of a cold front will move across the northern Gulf this evening and will support fresh to strong NW winds N of 31N through early Thu with building seas to 8 or 9 ft. Winds and seas will diminish Thu morning, but will resume again Sat evening as a cold front approaches the N Gulf of California and the pressure gradient tightens. Gulf of Tehunatepec: Fresh to strong northerly winds are expected in the Tehunatepec region early Sat morning, and again early Sun morning, with seas building to 8 or 9 ft. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... An area of low pressure located just off the west coast of Nicaragua continues to produce disorganized showers and thunderstorms. This system is expected to meander over the far eastern North Pacific, and gradual development is possible during the next several days if the disturbance remains offshore. Regardless of development, this system is likely to produce areas of heavy rain over portions of Central America during the next few days. These rains could cause flash flooding and mudslides in areas of mountainous terrain. Elsewhere, mainly light to gentle winds will persist N of the monsoon trough, with gentle to moderate S to SW winds S of the monsoon trough. Seas of 5 to 7 ft in SW swell are expected through least Fri. REMAINDER OF THE AREA... A ridge extends east-southeastward from a 1031 mb high at 41N138W to near the Revillagigedo Islands. The pressure gradient between the ridge and lower pressures in the vicinity of the ITCZ supports an area of fresh to locally strong trades from 15N to 24N W of 130W. The latest scatterometer pass confirmed the presence of these wind speeds. Seas of 8 ft are noted within the area of the trades. Seas will slightly increase to 9 ft on Thu in wind waves and SW swell. Cross equatorial SW swell is producing an area of 8 ft seas from 06N to 10N between 92W and 102W. Additional pulses of SW swell will increase the area of 8 ft seas by Fri, covering the waters S of 09N between 97W and 117W. $$ GR/MMT […]