000 AXPZ20 KNHC 311501 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1357 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 1200 UTC surface analysis and satellite imagery through 1500 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 98W, 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 87W and 94W. Areas of thunderstorms are impacting portions of Central America from Nicaragua northwestward to Southern Mexico and the Gulf of Tehuantepec. The gyre will move slowly northward, gradually encompassing much of Central America and southern Mexico within the next 24 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 Storm Amanda... Tropical Storm Amanda is embedded within the gyre. Amanda has moved inland over Guatemala, and centered near 14.7N 90.3W at 31/1500 UTC moving NNE at 8 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. As this small system is embedded within the larger gyre, the main impacts from Amanda will be to focus locally heavy rains near the center. For more on Amanda, please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 14.5N92W to low pres near 08N119W to low pres near 09N131W to 09N140W. Scattered moderate to strong convection is noted N of 00N E of 87W. Numerous moderate and scattered strong convection is noted N of 05N between 87W and 97W. Scattered moderate isolated strong convection is noted from 04N to 10N between 97W and 120W. Scattered moderate isolated strong convection is noted from 05N to 09N W of 130W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more details on the Central American Gyre, and embedded TS Amanda. 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 just below gale force across the Gulf of Tehuantepec. The area of high pressure will weaken enough to allow winds to gradually diminish below 25 kt by early Monday. Outside of the winds and seas associated to those features, fresh to locally strong winds prevail off Baja California Norte while fresh winds turn cyclonically off Cabo San Lucas. Gentle winds prevail elsewhere. Seas are in the 6-8 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. TS Amanda, embedded within the gyre circulation, has moved inland over Guatemala. These features are bringing active weather over the southern Mexico offshore waters, which will continue into early next week. Strong winds over the Gulf of Tehuantepec will persist through 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 TS Amanda. Outside of winds and seas associated to the Central American Gyre and TS Amanda, moderate to fresh winds prevail N of 02N, and gentle to moderate winds S of 02N. Seas are 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. TS Amanda, embedded within the gyre circulation, has moved inland over Guatemala. Hazardous marine conditions will prevail over the forecast waters west of Costa Rica and northward to Guatemala through early next week, with occasional 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 prevails across the northern waters. The pressure gradient between the area of high pressure and low pressure within the monsoon trough is supporting moderate to locally fresh winds N of the monsoon trough to near 10N 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 between 103W and 121W, where seas are 7-8 ft. Light to gentle southerly winds prevail elsewhere W of 121W. Seas over the discussion area are in the 5-7 ft range. The area of high pressure will weaken slightlytoday. A surface low will drift into the far NW portion of the discussion waters into Monday. The low will weaken into a trough by Tuesday and dissipate by Wed. High pres will then build it its wake. $$ AL