000 AXPZ20 KNHC 152141 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sun Jun 15 2025 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 2120 UTC. ...SPECIAL FEATURES... Tropical Storm Dalila is centered near 18.2N 108.4W at 2100 UTC, moving west-northwest at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Seas of 12 ft and greater extend outward to 120 nm to the NE, 90 nm to the SE, 60 nm to the SW, and 75 nm across the NW quadrants. Peak seas are estimated at 18 ft or 5.5 meters. Dalila continues to weaken this afternoon as it is entraining drier more stable low to middle-level from the NW, and moving into progressively cooler water temperatures. Convection has diminished considerably throughout the day, with widely scattered moderate convection currently displaced 120 to 310 nm to the southwest of the center. Dalila will continue to weaken as it moves towards the west later tonight through Tue. Dalia is expected to become a 30 kt post tropical system tonight near 18.3N 109.6W, then continue westward and slowly weaken, before dissipating W of 116W Tue night. Please refer to the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest T.S. Dalila NHC Forecast Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave across the Yucatan Peninsula, Central America and into the eastern Tropical Pacific along 88W-89W earlier today has become sheared, NW to SE across this area, with the southern portion becoming absorbed within the elongated cyclonic circulation about the monsoon trough E of 95W. It is no longer distinguishable and has been dropped from the 1800 UTC analysis. An ill-defined 1009 mb surface low remains in the area along the monsoon trough near 09.5N88.5W, accompanied by active convection described below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W to low pres 1009 mb near 09.5N88.5W to 13N104W to 10N121W. The ITCZ extends from 10N121W to beyond 09N140W. Widely scattered moderate convection is N of 03.4S and E of 84.5W. Scattered moderate to strong convection is noted from 03.5N to 14N between 85W and 96W, from 08N to 13N between 97W and 114W, and from 08N to 11.5N between 132W and 136W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for information on Tropical Storm Dalila. The expected weakening of Dalila is well underway this afternoon, as it moves slowly W-NW and away from the coast of Mexico to the southwest of Cabo Corrientes. Strong S-SE winds still persist across the near shore waters from Manzanillo to Cabo Corrientes. Seas to 12 ft associated with Dalila have shifted to beyond 60 nm of the coast there. However seas to 8 ft and greater associated with Dalila spread from near the coast of Cabo San Lucas to Las Tres Marias and along the Mexican coast to Oaxaca. Elsewhere, a broad and weak ridge extends from a 1026 mb high centered well NW of the area near 34N140W to well offshore of Baja California near 22N118W. This pattern is supporting moderate to locally fresh NW winds across the offshore waters of Baja California where seas are 5 to 7 ft in S swell. Light to gentle winds are ongoing in the northern Gulf of California with seas less than 3 ft. In the southern half of the Gulf winds are moderate from the S with seas of 3 to 6 ft in S swell. Gentle to locally moderate westerly winds are across the Gulf of Tehuantepec with 7 to 8 ft in SW swell. For the forecast, Dalila continues to weaken and will move more W and away from the coast of SW Mexico tonight, reaching near 18.3N 109.6W tonight as a 30 kt post-tropical system, and continue westward and slowly weaken through Mon, before dissipating west of 116W Tue night. Cross- equatorial southerly swell will continue to impact the waters between Tehuantepec and Baja California Sur through early MOn. Elsewhere, high pressure well northwest of the area will support generally moderate to locally fresh N-NW winds across the Baja California offshore waters through Tue, then weaken across Baja Sur through Thu night. NW to N swell will build into the Baja waters Mon evening through Thu night. Moderate to locally fresh southerly winds will prevail across the Gulf of California tonight through Tue. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Active showers and thunderstorms continue across interior portions of Central America N of 10N, and extend westward across much of the waters of Guatemala, El Salvador, Nicaragua and northern Cost Rico, and are associated with an elongated monsoonal circulation that currently prevails between 75W and 93W. An associated 1009 mb low southwest of Papagayo along 88.5W is producing fresh to locally strong easterly winds across the Papagayo region, and moderate S to SW winds over the Costa Rica offshore waters. Seas are 6-9 ft in S swell across this area. N of 10N and 5-8 ft S of 10N. Elsewhere across the remainder Central America offshore waters N of 04N, winds are gentle, and seas are moderate, and still 5 to 8 ft,in strong cross- equatorial S swell. Winds S of 04N and between Ecuador and the Galapagos Islands are moderate from the S and SE, with and seas 6 to 8 ft in S swell. For the forecast, large S to SW swell dominating the regional waters will slowly subside through early next week. Tropical Storm Dalila is weakening and will turn more W tonight through Tue, moving away from the Mexican coast. Low pressure offshore NW Costa Rica is expected to drift W to W-NW through the middle of next week. Environmental conditions appear conducive for gradual development of the low, and a tropical depression is likely to form by the middle of this coming week while moving westward to west-northwestward and just offshore of the coasts of El Salvador, Guatemala, and southeastern Mexico. Showers and thunderstorms are expected to remain active across the regional waters in association with this system. This system is being monitored for potential tropical development, and has a medium chance of formation through 48 hours, and a high chance through 7 days. ...REMAINDER OF THE AREA... Please read the Special Features section for information on Tropical Storm Dalila, located a few hundred nautical miles southwest of Cabo Corrientes, Mexico. Broad and weak ridging centered on a 1026 mb high near 34N140W dominates the waters north of 15N and W of 120W. This pattern is supporting moderate to locally fresh NE winds north of 10N and west of 130W, with 5 to 6 ft seas in a mix of N and S swell. Gentle to moderate winds prevail north of the ITCZ and monsoon trough to 24N between 115W and 130W, where seas are 5 to 7 ft, except to 8 ft and higher closer to Dalila. North of 24N, moderate to fresh N to NE winds prevail between 120W and 130W, with seas of 6 to 8 ft. Southerly swell is slowly subsiding east of 115W, however seas there remain 6 to 8 ft. Elsewhere south of the monsoon/ITCZ, winds and seas are mainly moderate. For the forecast, high pressure north of the area will sink slightly southward through Tue, then the ridge will reorganize from the NW to basically reinforce the current pattern. A slight increase in winds is expected N of 20N through Tue night, while winds weaken to the W and SW of the approaching remnants of Dalila during the next few days. A slight increase in seas is expected across the northern waters E of 130W Mon night through Thu as new N to NE swell moves into the regional waters. $$ Stripling