000 AXPZ20 KNHC 260258 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...SPECIAL FEATURES... Tropical Storm Boris is centered near 11.4N 137.9W at 26/0300 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. Numerous moderate and isolated strong convection is noted within 180 nm of the center. Little change in strength is forecast overnight with weakening thereafter. 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 1005 mb broad area of low pressure near 15N104W along a tropical wave, or a few hundred miles south of the southwestern coast of Mexico remain disorganized. Scattered moderate and isolated strong convection is noted within 19N103W to 16N98W to 06N98W to 07N107W to 14N102W to 19N103W. Little deep convection is located near the actual broad low pressure area. Earlier scatterometer data showed an elongated area of fresh to strong easterly winds off the southern coast of Mexico, roughly between Manzanillo and the Tehuantepec region. Environmental conditions are forecast to be conducive for some 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. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave axis is along 97W, moving westward at around 10 kt. Scattered moderate and isolated strong convection is noted within 16N96W to 16N87W to 05N94W to 11.5N98.5W to 16N96W. An area of low pressure may 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 104W, moving westward at around 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 northern Colombia near 09N74W to 07N82W to low pressure near 15N104W to low pressure near 14.5N122W to 11N132W. Scattered moderate and isolated strong convection is noted from 04N to 06N between 81W and 87W. Scattered moderate convection is noted from 07.5N to 11N between 108W and 122W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for more details about the area of low pressure along a tropical wave near 104W. Elsewhere, mainly gentle to moderate NW-N winds prevail offshore of Baja California. Southerly winds remain gentle to moderate in the Gulf of California, east of a trough axis that extends along the Baja peninsula. The trough along the Baja peninsula will support increasing winds and seas in the Gulf of California late tonight through early next week. 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 across the Guatemala and El Salvador offshore waters. Seas are 6-10 ft in this region. Elsewhere, gentle to moderate monsoonal flow continues over the offshore waters roughly S of 08N per earlier scatterometer data. Scattered showers and isolated 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. Earlier scatterometer data indicated moderate to fresh monsoonal flow persists south of the monsoon trough between 90W and 105W. Fresh winds and SW swell are likely producing 7-9 ft combined seas in this region. Moderate to fresh N-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. A set of northerly swell will spread south of 30N Sat night through early next week building seas to 7-9 ft N of 27N. 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 later tonight 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. $$ Lewitsky