000 AXPZ20 KNHC 172206 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Aug 17 2023 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 2145 UTC. ...SPECIAL FEATURES... Hurricane Hilary is centered near 16.1N 108.9W at 17/2100 UTC, or about 410 nm nm south of Cabo San Lucas moving west-northwest at 12 kt. Estimated minimum central pressure is 960 mb. Maximum sustained wind speed is 95 kt with gusts to 115 kt. Satellite imagery shows that Hilary continues to rapidly intensify as noted in its impressive and large cloud pattern that consists of numerous strong convection within 60 nm of the center in the E semicircle. Numerous moderate to strong convection is present within 120 nm of the center in the SW quadrant and 90 nm of the center in the NW quadrant. Numerous moderate isolated strong convection is elsewhere from 10N to 19N between 102W-110W, and within an outer rain band that extends from 20N110W to 15N113W. Peak seas are 36 ft. The 12 ft radii continues to expand as Hilary intensifies. It extends outward within 300 nm in the NE quadrant, 330 nm in the SE quadrant and 180 nm in the W semicircle. Meanwhile, the elsewhere 8-12 ft seas cover the area roughly from 06N to 23N between 98W-114W. Hilary is forecast to turn toward the northwest is expected Fri morning, followed by a turn toward the north-northwest and north on Sat. On the forecast track, the center of Hilary will approach the Baja California peninsula over the weekend. Rapid strengthening is forecast during the next day or so, and Hilary could become a major hurricane later today. Large swells generated by Hilary will affect portions of the coast of southwestern Mexico and the Baja California peninsula over the next few days. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. Interests elsewhere on the Baja California peninsula and along the coast of northwestern mainland Mexico and the southwestern United States coastline should closely monitor the progress of Hilary. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Hilary NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 93W from 04N northward to across western Guatemala. It is moving westward around 10 kt. Scattered moderate to isolated strong convection is within 120 nm west of the wave from 06N to 12N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwest Colombia to 09N84W to 08N90W to 10N97W. It resumes west-southwest of Hurricane Hilary from near 12N113W to 10N125W and to 07N135W. The ITCZ extends from 07N135W to beyond 07N140W. Scattered moderate to isolated strong convection is seen from 04N to 07N between 85W-93W. Scattered moderate convection is within 60 nm south of the trough between 114W-118W and within 60 nm of the trough between 124W-135W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information on Hurricane Hilary that is approaching major hurricane status. Outside of Hurricane Hilary, generally weak high pressure is present over the offshore forecast waters of Baja California. The associated gradient is allowing for moderate to locally fresh NW to N of Cabo San Lazaro, with gentle to moderate winds elsewhere in the Baja California offshore waters. Seas are 4-6 ft. In the Gulf of California, light to gentle winds are noted along with seas of 1-2 ft, except seas of 3-4 ft near the entrance to the Gulf. Pulses of moderate to fresh N winds are and seas to about are in the Tehuantepec region. For the forecast, Hurricane Hilary will continue to strengthen as it reaches near 16.4N 109.4W this evening with maximum sustained winds 100 kt gusts 120 kt, to near 17.0N 110.4W late tonight with maximum sustained winds 110 kt gusts 135 kt, to near 18.4N 112.0W Fri afternoon with maximum sustained winds 120 kt gusts 145 kt, maintain intensity as it nears 20.3N 113.0W late Fri night then begin to gradually weaken as it nears 22.2N 113.8W Sat afternoon with maximum sustained winds 115 kt gusts 140 kt, to near 25.0N 114.5W late Sat night with maximum sustained winds 105 kt gusts 130 kt, to near and to near 28.5N 115.4W early Sun afternoon with maximum sustained winds 85 kt gusts 105 kt. Hilary is forecast to weaken to a tropical depression while moving inland near 35.4N 118.4W Mon afternoon. Looking ahead, a broad area of low pressure could form offshore of the coast of southern Mexico during the early or middle part of next week. Some gradual development of this system is possible thereafter while it moves slowly west-northwestward or northwestward. This system has a low chance of tropical cyclone development over the next 48 hours and 7 days. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh northeast to east winds are in the Papagayo region and downwind to about 89W. Seas are 5-7 ft with these winds. Gentle to moderate winds and seas in the 4 to 6 ft range prevail elsewhere across the Central and South America forecast waters, with the exception of 1-3 ft seas in the Gulf of Panama, and 3-4 ft just offshore Colombia. For the forecast, the moderate to fresh northeast to east winds in the Gulf of Papagayo region will pulse to fresh to strong speeds at night and into the mornings through Fri night, then to fresh speeds through early next week. Elsewhere gentle to moderate winds and moderate seas are expected through the upcoming weekend. ...REMAINDER OF THE AREA... The remnant low of former tropical cyclone Fernanda is near 16N133W with a pressure of 1005 mb. Strong to near gale-force winds are within 180 nm of the center in the N semicircle and 60 nm of the center in the S semicircle with seas of 9-14 ft. No deep convection is observed with the low as satellite imagery depicts it as a swirl of broken to overcast low and mid-level clouds with possible scattered showers from 14N to 20N between 130W-139W. Generally weak high pressure is over the area surrounding the low. The pressure gradient between the ridge and the remnant low pressure supports an area of moderate to fresh winds from 18N to 23N between 125W-138W. Light to gentle winds are noted elsewhere under the influence of the ridge. Moderate to fresh winds are noted south of the monsoon trough roughly between 100W-130W. Elswhere, seas are 4-7 ft, primarily in NW swell N of 20N W of 120W, and SW swell elsewhere. $$ Aguirre