000 AXPZ20 KNHC 042040 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1831 UTC Thu Jun 4 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... ...Heavy rainfall across Central America and Southern Mexico... A Central American Gyre remains centered over southern Mexico and northern Central America, with the broad cyclonic circulation around the gyre encompassing the discussion waters N of 10N and E of 100W, and extending across adjacent portions of the southern Gulf of Mexico to 25N and the western Caribbean Sea to 80W. The Central America Gyre produces a northward displacement of the monsoon trough over Central America, and it is most common in late spring and early fall. The associated deep convection is usually found on the southern and eastern sides of the circulation. Currently, numerous moderate to scattered strong convection is noted over the Yucatan Peninsula. Similar convection is noted in a band extending between San Andres Island and the coast of Nicaragua, crossing near Cabo Gracias a Dios, and all the way to the NW to Cancun, Mexico. Scattered moderate convection is noted over portions of Guatemala, Belize, and El Salvador as well as across the Pacific coast of Central America between the Gulf of Papagayo and the Gulf of Fonseca. Cristobal, now as a tropical depression, remains embedded within the larger circulation of the gyre, and will continue to produce additional heavy rainfall over portions of SE Mexico and northern Central America during the next few days. Winds flowing around the larger Central American Gyre will continue to bring abundant tropical moisture cyclonically across portions of Central America and SE Mexico for the next few days, bringing additional heavy rains to Guatemala, El Salvador, Honduras and Nicaragua. This setup will maintain a very dangerous situation for these areas. This large quasi-stationary circulation has brought heavy rainfall and severe flooding to portions of Central America and southern Mexico during the past several days, and deadly flooding has already occurred in portions of Guatemala and El Salvador. During the past 24 hours, ending this morning at 8 am, the Mexican Weather Service reported rainfall accumulations of 5-10 inches across the states of Veracruz, Tabasco, Chiapas, and Campeche. In El Salvador, the highest rainfall amounts occured in the SW part of the country during the last 24 hours. Additional rainfall accumulations of 6-12 inches are possible over the Mexican states of Campeche, Quintana Roo, Tabasco and Yucatan during the next few days, with rainfall amounts of 5 to 10 inches over Veracruz and Oaxaca. The rains will lead to additional life-threatening flash floods and mudslides, especially in areas of mountainous terrain. Please refer to products issued by your local or national meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 13N94W to 1012 mb low pres located near 11N115W to 10N120W. The ITCZ continues from 10N120W to 08N130W. A trough is within the ITCZ and extends from 13N132W to 07N136W. Numerous moderate to isolated strong convection is noted from 08N to 13N between 94W and 101W. Similar convection is just W of the above mentioned low pres from 08N to 11N between 115W and 124W. A cluster of moderate to isolated strong convection is near the Gulf of Tehuantepec at 15N95W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more details on the Central American Gyre. Gentle to moderate NW winds will prevail across the offshore waters of Baja California through early Sat, with the exception of fresh to strong NW winds along and well offshore of the coast of Cabo San Lucas through Sat night. Seas will build to 6-9 ft in SW swell across the waters between Las Marias and Cabo San Lazaro today. As high pressure builds across the area during the upcoming weekend, expect fresh to strong northerly winds N of Punta Eugenia, and fresh winds S of Punta Eugenia. In the Gulf of California mainly gentle to moderate winds will prevail, except across the northern part of the Gulf where a surface trough and tight pressure gradient will support strong winds and building seas to 6-9 ft tonight through Fri night. The Central American Gyre will continue to produce onshore flow and very active weather across the waters of southern Mexico over the next few days. 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. This will continue to bring active weather across Central America. Moderate to fresh onshore winds will prevail across the forecast waters of Guatemala and El Salvador through Fri, with building seas of 7-10 ft in mixed SW swell. Mainly gentle to moderate SW to W winds are expected elsewhere, with the exception of SE to S winds across the waters between Ecuador and the Galapagos Islands. Large long-period SW swell will continue to propagate across the region through late Fri. Another round of cross equatorial SW swell is forecast to reach the waters between Ecuador and the Galapagos Islands this weekend. REMAINDER OF THE AREA... High pressure of 1025 mb located well N of the area extends a ridge across the northern forecast waters to near Clarion Island. Moderate to locally fresh trade winds are expected along the southern periphery of the ridge and N of the ITCZ over the next few days. This high pressure system will continue to build across the northern waters through the week and act to strengthen the trade winds S of 20N and W of 130W over the weekend. Southerly swell will continue to propagated across the forecast waters mainly S of 15N between 90W-120W supporting seas of 8-10 ft per recent altimeter data. Seas will gradually subside tonight through Fri, but another SW swell event will reach the waters S of the Equator Fri night into Sat. $$ GR