923 AXPZ20 KNHC 130308 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...SPECIAL FEATURE... Tropical Storm Calvin is centered near 12.6N 114.9W at 13/0300 UTC, moving W at 15 kt. Estimated minimum central pressure is 995 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Numerous moderate to strong convection prevails from 09N to 14N between 111W and 119W. Additional strengthening is forecast during the next couple of days, and Calvin is forecast to become a hurricane later tonight. Seas will continue to build over the next few days and peaking over 30 ft from Thu night 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 91W and N of 06N, moving W at 10 to 15 kt. Scattered moderate convection prevails along the northern portion of the wave mainly N of 13N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 12N107W, then resumes near 13N119W to 12N128W. The ITCZ continues from 12N128W to beyond 07N140W. Scattered moderate convection is noted from 03N to 14N and E of 106W and from 04N to 13N and W of 126W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak surface ridge dominates the offshore forecast waters of Baja California. Moderate to fresh winds with seas to 5 ft are noted in the Gulf of Tehuantepec. Moderate to fresh winds and seas to 6 ft are over the outer offshore waters of Cabo Corrientes. This is due to the outer portion influences of TS Calvin. Moderate winds are noted in the northern Gulf of California. 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, reaching 4 ft at the entrance to the Gulf. Seas of 4-5 ft prevail elsewhere. For the forecast, northerly winds will pulse to moderate to fresh at night in the Gulf of Tehuantepec through the weekend. Tropical Storm Calvin is located several hundred miles southwest of the southwestern coast of Mexico. The system could bring 8 ft seas in the outer offshore waters of the southern Baja California offshore waters on Thu. These seas will subside by Thu night. Otherwise, Tropical Storm 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 4-5 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 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 forecast period. ...REMAINDER OF THE AREA... Please see the SPECIAL FEATURES section above for more information on Tropical Storm Calvin. Aside from T.S. Calvin, high pressure prevails north of 20N anchored by a 1025 mb high pressure center N of the area near 32N149W. The pressure gradient between this area of high pressure and the ITCZ/monsoon trough is supporting moderate to fresh winds N of the ITCZ and W of 125W. An area of 8-9 ft seas is noted from 07N to 17N and W of 135W. Otherwise, seas range 6-8 ft in northerly swell. To the south of the ITCZ and monsoon trough, gentle to moderate winds are noted. Southerly swell with seas to 8 ft are noted S of 02N and west of 135W. Seas of 5-7 ft are elsewhere across the waters S of 10N and W of 90W. For the forecast, the main feature between 10N and 20N is T.S. Calvin which will continue moving westward through the weekend. Calvin will strengthen to a hurricane near 12.7N 117.0W Thu morning, move to 13.0N 119.7W Thu evening, 13.7N 122.5W Fri morning, 14.4N 125.4W Fri evening, 15.0N 128.4W Sat morning, and 15.6N 131.4W Sat evening. Calvin will then weaken to a tropical storm near 16.7N 138.0W by late Sun. N of 20N, gentle to moderate winds and seas of 5-7 ft will prevail through Fri. S of 10N, gentle to moderate winds will prevail through the weekend. Southerly swell bringing 8 ft seas will continue to subside tonight. Seas of 4-7 ft is expected to prevail over the next few days before Calvin approaches the area. $$ ERA