000 AXPZ20 KNHC 252050 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2050 UTC Thu Jun 25 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 2030 UTC. ...SPECIAL FEATURES... Tropical Storm Boris is centered near 11.2N 137.1W at 25/2100 UTC moving WNW at 8 kt. Estimated minimum central pressure is 1005 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Scattered moderate convection is noted within 90 nm NW semicircle. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP3.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP3.shtml for more details. Showers and thunderstorms associated with a broad area of low pressure and a tropical wave along 103.5W remain disorganized. Numerous moderate and isolated strong convection is noted north of 15N between 98W and 103W. Elsewhere, scattered moderate convection is occurring north of 11N within 300 nm east of the wave axis. Environmental conditions are forecast to be conducive for gradual development, and the system could become a tropical depression within the next couple of days while it moves west- northwestward parallel to the coast of Mexico. This system has a medium chance of tropical cyclone formation during the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave axis is along 96W, moving westward at 15 kt. Numerous moderate convection is noted from 10N to 14N within 120 nm of the wave axis. An area of low pressure is forecast to form south of the Gulf of Tehuantepec this weekend or early next week. Gradual development of this system is possible next week as it moves west-northwestward parallel to the coast of Mexico. This system has a low chance of tropical cyclone formation during the next five days. A tropical wave axis is along 103.5W, moving westward at 10 kt. See the Special Features section above for more details on this wave and the potential for tropical cyclone development. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N77W to 05N83W to 1006 mb low pressure near 14N103.5W to 1008 mb low pressure near 14N122W to 09N140W. Numerous moderate and isolated strong convection is noted north of 04N and east of 82W. Elsewhere, scattered moderate and isolated strong convection is occurring within 180 nm of the monsoon trough between 88W and 93W. Scattered moderate convection is noted from 09N to 11N between 114W and 118W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent scatterometer data shows an elongated area of fresh to strong easterly winds off the southern coast of Mexico, roughly between Manzanillo and the Tehuantepec region. This is associated with a broad area of low pressure centered along a tropical wave near 103.5W. Wave heights are building to 6-8 ft within these strong winds. Elsewhere, mainly gentle NW winds prevail offshore of Baja California, except for some locally moderate winds near Cabo San Lucas. Southerly winds remain gentle to moderate in the Gulf of California, east of a trough axis that extends along the Baja peninsula. A trough along the Baja peninsula will support increased winds and seas in the Gulf of California late tonight through early next week. Winds and seas will increase off the coast of southern Mexico tonight into this weekend as a low pressure system and a vigorous tropical wave move parallel to the coast of Mexico. Please see the NHC Tropical Weather Outlook for the latest updates. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A band of fresh to locally strong easterly winds extends from the Papagayo region westward across the Guatemala and El Salvador offshore waters. Seas are building to 6-9 ft in this region. Elsewhere, gentle to moderate monsoonal flow continues over the offshore waters roughly S of 08N per recent scatterometer data. Numerous showers and thunderstorms are noted along the monsoon trough offshore of Panama and Colombia, likely producing locally gusty winds and locally rough seas. Fresh to strong winds will pulse over and downstream of the Papagayo region through early next week. Wave heights will peak around 8 ft each morning. Moderate to occasionally fresh monsoon flow will prevail over the waters S of 10N through this weekend. Looking ahead, building seas are possible W of 85W Mon night through Tue night as monsoonal flow freshens across the region and SW swell propagates through the waters. REMAINDER OF THE AREA... Please see the Special Features section above for more details on Tropical Storm Boris, as well as the potential for additional tropical cyclone development later this week. Scatterometer data indicate moderate to fresh monsoonal flow persists south of the monsoon trough between 90W and 110W. Fresh winds and SW swell are likely producing 7-9 ft combined seas in this region. Moderate to fresh NE flow continues between T.S. Boris and a high pressure ridge that extends across the northern waters, with seas generally 5-7 ft. A weak low-level circulation is noted in scatterometer winds near 14.5N122W, but associated wind speeds are less than 20 kt. Cross-equatorial southerly swell, combined with freshening monsoon flow, will build seas south of the monsoon trough and east of 120W by this weekend. Seas are expected to build to 8-9 ft south of the Equator Fri through Sun in SW swell, then subside on Mon. Looking ahead, another SW swell event is possible over the far southern waters Tue and Tue night. $$ B Reinhart