737 AXPZ20 KNHC 010247 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Sep 1 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 0200 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from the Panama-Costa Rica border to near 10N86W to 12N108W to 06N126W. The ITCZ continues from 06N126W to 08N135W. Scattered moderate convection is noted from 02N to 09N between 77W and 98W and from 05N to 12N between 106W and 118W. Scattered moderate convection is noted from 04N to 15N between 98W and 106W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad surface trough extends from 17N116W to 1007 mb low pressure near 21N114W to 25N112W. Upper-level diffluence is enhancing scattered moderate convection across Baja Sur and from the southern Gulf of California southward. Light to gentle winds dominate the waters, except in the Gulf of California where moderate to locally fresh S winds prevail. Seas are 5-7 ft offshore Baja California, 4-5 ft in the northern Gulf of California, 2-3 ft elsewhere in the Gulf, and 5-6 ft elsewhere off Mexico in S swell. For the forecast, pulsing fresh to strong S winds will continue in the northern Gulf of California through Fri night. Fresh to strong northerly winds will pulse in the Gulf of Tehuantepec Fri night through Sat night. Winds will be moderate or weaker elsewhere through Sat. Winds will increase to fresh nearshore Baja California Sun night through Mon night as the pressure gradient tightens along the peninsula. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds prevail across the offshore waters N of 04N, except for moderate NE to E winds in the Papagayo region, and stronger gusts possible in thunderstorm activity near Panama and Costa Rica. Seas north of 04N are 5-7 ft in long-period south to southwest swell. To the south of 04N, including the waters offshore southern Colombia and in between Ecuador and the Galapagos Islands, moderate S winds with seas of 6 to 8 ft are present due to long-period S to SW swell. Scattered tstms are noted off Colombia, Panama, and Costa Rica ahead of a tropical wave and weak low pressure currently over the far SW Caribbean Sea. For the forecast, moderate to locally fresh south to southwest winds will continue between the coast of Ecuador and the Galapagos Islands most of the time through the weekend. Southerly swell of 7-9 ft will subside only slightly this evening. Then, renewed long period S to SW swell will move through those waters Fri into Sat, increasing seas back to 8-9 ft through early Sun. Swell of 6-8 ft will reach the waters offshore Panama and Costa Rica late Sat through late Sun. Elsewhere, light to gentle variable winds will prevail through most of the the forecast, locally and occasionally moderate to fresh near the Gulfs of Papagayo and Fonseca, along with slight to moderate seas in long- period SW swell. Enhanced showers and thunderstorms will continue off Panama and Costa Rica through tonight. ...REMAINDER OF THE AREA... The post-tropical remnant low of former Tropical Cyclone Irwin is centered near 19N 139W with an estimated central pressure of 1009 mb. It is moving westward at 5 to 10 kt. A tight pressure gradient between the low and strong high pressure to its north is keeping strong to near gale force winds in the northwest semicircle from the low to 24N between 136W and 140W. Seas are 10-13 ft in this area. Elsewhere north of 20N and west of 123W, fresh N to NE winds and 8 to 10 ft seas prevail. Winds are mainly moderate or weaker across the remainder of the open waters, with seas 6-8 ft. For the forecast, the post-tropical remnant low of Irwin will continue moving westward, with a slightly slower motion expected, reaching 140W Fri. Fresh to strong winds and elevated seas will continue to accompany the low, mainly in the NW semicircle. Elsewhere, northerly swell will propagate through the open waters well W of Baja California through early Fri, keeping seas of 6-10 ft N of 20N and W of 120W. Long period S swell will push northward across the Equator late tonight and Fri with seas of 8-9 ft south of 06N and east of 120W into Sat before subsiding late in the weekend. The broad north-south oriented surface trough with accompanying low pressure is expected to move from along 114W to 120W by the weekend, resulting in shifting winds. $$ KONARIK