National Hurricane Center's Tropical Weather Discussion

Eastern Pacific Ocean

365 AXPZ20 KNHC 310314 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun May 31 2020 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 0000 UTC surface analysis and satellite imagery through 0220 UTC. ...SPECIAL FEATURES... ...Heavy rainfall in Central America... A Central American Gyre is over the eastern North Pacific, with the broad cyclonic circulation around the gyre encompassing the discussion waters N of the equator and E of 100W, including portions of southern Mexico and Central America. Moderate to strong winds are noted across much of these waters, with seas in the 6-10 ft range. Numerous moderate and scattered strong convection is noted across much of these waters, particularly N of 10N between 85W and 95W. Areas of thunderstorms are impacting portions of Central America from the W part of Nicaragua northward to Southern Mexico. The gyre will move slowly northward, gradually encompassing much of Central America and southern Mexico within the next 24-48 hours. Winds around the gyre will continue to advect abundant moisture into portions of Central America and southeastern Mexico for the next several days. This will create a dangerous situation for these areas with an extended period of active and wet weather, and periods of heavy rainfall, through the weekend and into next week, especially over southern Guatemala, El Salvador, southern Honduras, western Nicaragua, and portions of southern Mexico E of Veracruz and eastern Oaxaca. This will bring the potential for life-threatening flash floods and mudslides for locations that receive the heaviest rainfall, especially in areas of mountainous terrain. Please refer to products issued by your local weather service for more details. ...Tropical Depression Two-E... Tropical cyclogenesis is possible in association with Central American Gyres, and a depression (TD Two-E) has developed within the gyre circulation and was centered near 13.0N90.6W moving NNE at 5 kt. The depression will continue to move NNE and inland over Guatemala Sunday and dissipate Sun night. As this small system is embedded within the larger gyre, the main impacts from TD Two-E will be to focus locally heavy rains near the center as it moves toward the coast. However, the larger threat will continue to be the Central American Gyre, which will linger across Central America and southern Mexico well after the TD dissipates. ...Gulf of Tehuantepec Gale Warning... The pressure gradient between a ridge of high pressure along the eastern slopes of the Sierra Madre Oriental and the Central American Gyre is producing gap winds to gale force this evening. These gale force NNW winds will continue in a narrow plume throughout the next 6 hours or so and then diminish slightly to near 30 kt and persist through Sunday morning. The area of high pressure will weaken enough to allow winds to gradually diminish below 25 kt by early Monday. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 15N89W to TD Two-E near 13.0N90.6W to low pres near 08N118W to low pres near 10N131W to 08N140W. Scattered moderate to strong convection is noted from 05N TO 10N E OF 105W, and from 04N TO 08.5N between 105W AND 127W. Scattered moderate isolated strong convection is from 06.5N TO 10N between 134W AND 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more details on the Central American Gyre, and embedded TD Two-E, as well as the gale warning in the Gulf of Tehuantepec. Outside of the winds and seas associated to those features, fresh to locally strong winds prevail off Baja California Norte while moderate to fresh winds are off Cabo San Lucas. Gentle to moderate winds prevail elsewhere off Baja California Sur, and gentle winds prevail elsewhere. Seas are in the 5-8 ft range over the open waters off Mexico, and in the 1-3 ft range over the Gulf of California. The Central American Gyre is progressing across the forecast waters toward the northern portion of Central America and southern Mexico. TD Two-E has developed within the gyre circulation. The depression will move inland over Guatemala on Sunday. These features will bring active weather over southern Mexico offshore waters this weekend into early next week. In addition, there will be a brief period of gale force winds over the Gulf of Tehuantepec tonight. Elsewhere, high pressure will build over the northern waters. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the Special Features section for more details on the Central American Gyre, and embedded TD Two-E. Outside of winds and seas associated to the Central American Gyre and TD Two-E, moderate to fresh winds prevail N of 02N, and gentle to moderate winds S of 02N. Seas in the 5-8 ft range prevail across the area. The Central American Gyre is progressing across the forecast waters toward the northern portion of Central America and southern Mexico. TD Two-E has developed within the gyre circulation. The depression will move inland over Guatemala on Sunday. Hazardous marine conditions will prevail over the forecast waters west of Costa Rica and northward to Guatemala through early next week, with large clusters of thunderstorms, fresh to strong winds, and building seas. Elsewhere, long- period SW swell will continue propagating across the region through early next week. REMAINDER OF THE AREA... High pressure has started to slowly build across the northern waters. The pressure gradient between the building high pressure and low pressure within the monsoon trough is supporting moderate to locally fresh winds N of the monsoon trough to near 12N and W of 125W. Light to gentle winds prevail elsewhere N of the monsoon trough. Moderate to fresh southerly winds prevail S of the monsoon trough E of 120W, and light to gentle southerly winds prevail W of 120W. Seas over the discussion area are in the 5-7 ft range, with a few small areas of seas to 8 ft. A high pressure ridge will continue to build across the northern waters this weekend, with little change in marine conditions expected over these outer waters over the next couple days. $$ Stripling