000 AXPZ20 KNHC 132158 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Jul 13 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 2130 UTC. ...SPECIAL FEATURE... Hurricane Calvin is centered near 12.8N 118.7W at 13/2100 UTC moving W at 12 kt. Estimated minimum central pressure is 990 mb. Maximum sustained wind speed is 70 kt with gusts to 85 kt. Numerous moderate to strong convection is noted from 10N to 17N between 115W and 122W. The 12 ft seas extend 150 nm in the NE quadrant, 120 nm in the NW quadrant, 90 nm in the SE quadrant and 60 nm in the SW quadrant with peak seas near 22 ft. Calvin will continue in a west to west- northwestward motion during the next few days. Some additional strengthening is forecast during the next day or so. Gradual weakening is forecast to begin by the weekend, as Calvin begins to move over cooler water. Seas will continue to build over the next few days and peaking over 30 ft from tonight through Sun morning. 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. ...TROPICAL WAVE... A tropical wave extends its axis along 95W and N of 06N to southern Mexico, moving W at 10 to 15 kt. Scattered moderate to isolated strong convection is noted along the wave from 09N to 16N between 93W and 99W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Panama near 08N83W to 09N95W to 10N109W. The ITCZ extends from 11N128W to beyond 09N140W. Scattered moderate to isolated strong convection is noted from 04N to 15N and E of 104W. Scattered moderate convection is noted from 06N to 12N between 126W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak surface ridge dominates the offshore forecast waters of Baja California. Moderate winds with seas to 5 ft are noted in the Gulf of Tehuantepec. Moderate winds and seas to 8 ft are over the outer offshore waters of Cabo Corrientes. This is due to the outer portion influences of Hurricane Calvin. Moderate to fresh winds are noted in the Oaxaca offshore waters due to the tropical wave with seas to 6 ft. Elsewhere, light to gentle winds prevail over the remainder of the Mexico offshore waters. Seas of 1-3 ft are over the Gulf of California. Seas of 4-5 ft prevail elsewhere. Strong thunderstorms are noted in the Oaxaca offshore waters due to the tropical wave described above. For the forecast, northerly winds will pulse to fresh to locally at night in the Gulf of Tehuantepec through the weekend. Hurricane Calvin is located several hundred miles southwest of the southern tip of Baja California. The system is bringing 8 ft seas in the outer offshore waters of the southern Baja California offshore waters today. These seas will subside by tonight. Otherwise, Hurricane Calvin will have little impact on the rest of the Mexico offshore waters. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh winds with seas of 5-6 ft persist in the Gulf of Papagayo. Light to gentle winds and seas of 4-6 ft are noted over the remainder of waters north of 02N. Gentle to moderate winds are noted south of 02N where seas are 4-6 ft. Scattered thunderstorms are noted across the Central American and Colombia offshore waters. For the forecast, gentle to moderate winds will prevail over the next several days. Fresh to strong gap winds across the Papagayo region will continue pulsing each evening through the weekend. ...REMAINDER OF THE AREA... Please see the SPECIAL FEATURES section above for more information on Hurricane Calvin. Aside from Calvin, high pressure prevails north of 20N anchored by a 1026 mb high pressure center N of the area near 34N136W. The pressure gradient between this area of high pressure and the ITCZ/monsoon trough is supporting gentle to moderate winds N of the ITCZ and W of 125W. An area of 8 ft seas is noted from 08N to 11N and W of 135W. S of the ITCZ, winds are gentle to moderate with seas ranging 5-7 ft in southerly swell. For the forecast, the main feature between 10N and 20N is Hurricane Calvin which will continue moving westward through the weekend. Hurricane Calvin will move to 13.2N 120.8W Fri morning, 13.7N 123.7W Fri afternoon, 14.3N 126.5W Sat morning, 14.9N 129.4W Sat afternoon, 15.6N 132.3W Sun morning, and 16.2N 135.2W Sun afternoon. Calvin will weaken to a tropical storm over 17.3N 141.9W by Mon afternoon. The area of 8 ft swell will subside tonight. N of 20N, gentle to moderate winds and seas of 5-7 ft will prevail through the weekend. S of 10N, gentle to moderate winds can be expected. Seas of 4-7 ft will prevail over the next few days before Calvin approaches the area. $$ AReinhart