000 AXPZ20 KNHC 301015 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Oct 30 2020 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning...High pressure and cooler, denser air follow a cold front that has moved across the western Gulf of Mexico and now extends along the far southwest Gulf of Mexico. Recent scatterometer data and regional observations suggest this cooler air has punched through the Tehuantepec isthmus and gale are likely ongoing into the Gulf of Tehuantepec. These winds are expected to reach 40 kt through late today then temporarily diminish to just below gale into Sat. A reinforcing front is expected to move into the southwest Gulf by late Sat, allowing a new round of gale force winds by Sun which should persist through early next week. Short period northerly swell will mix with longer period southerly swell to support seas in excess of 8 ft well downstream of the Gulf of Tehuantepec. Peak seas during this gale wind event are expected to build to around 16 ft Fri afternoon and then to near 18 ft Mon evening. ...TROPICAL WAVES... A tropical wave axis is along 86W, along the east coast of Nicaragua, extending southward across Costa Rica to 05N, moving westward at 15-20 kt. Associated convection is described below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 11N85W to 14N110W to beyond 10N140W. Scattered moderate to strong convection is noted from 06N to 10N between 87W and 92W, from 10N to 13N between 95W and 100W, and from 10N to 14N between 112W and 118W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure west of Baja California is supporting gentle to moderate northerly breezes across the Mexican offshore waters off Baja California and the Gulf of California. Seas are mostly 2 to 4 ft in both the open waters and in the Gulf of California. Divergence aloft on the southeast side of an upper trough west of the area is supporting a few showers near the Revillagigedo Islands. Seas will build to 4 to 6 ft in the waters of Baja California by early next week. Elsewhere, little change is expected through the next several days. Farther south, moderate northerly winds are funneling off Cabo Corrientes, and seas are likely 4 to 6 ft off the Jalisco and Colima coasts in mostly southerly swell. Gentle winds and 3 to 5 ft elsewhere off southern Mexico outside of the Gulf of Tehuantepec. Seas will start building tonight as increased southerly swell moves into the area, reaching up to 9 ft off Michoacan and Guerrero by late Sat, then subsiding into early next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate south to southwest winds will prevail south of the monsoon trough through Sun, with isolated areas of fresh winds this afternoon overnight ahead of an approaching tropical wave. Seas are expected to increase offshore of Guatemala and El Salvador through Sat night due to gale force winds in the Gulf of Tehuantepec pushing northerly waves into the area. Moderate offshore gap winds are expected across the Papagayo region through Sun before turning onshore Mon. Active weather is expected across the waters north of 05N, from the Papagayo region southeast into Central America and the Gulf of Panama this afternoon and tonight. REMAINDER OF THE AREA... A broad ridge persists across the northern forecast waters west of 120W. The gradient between the ridge and lower pressures associated with the monsoon trough will support moderate to fresh NE trade winds over an area roughly from 10N to 22N, west of 115W, for the next several days. Seas are 6 to 8 ft across this region, in a mix of swell and easterly wind waves. Little change is expected through today. South of the monsoon trough, moderate to fresh S to SW winds prevail between 100W and 130W, where seas are 7-9 ft. Minor fluctuations in winds and seas are expected across this area through the weekend. Looking ahead, computer models suggest that a tropical wave moving offshore of SW Mexico Sun and Mon could spawn a low pressure center forming west of the offshore waters in the vicinity of 10N110W by Mon morning, and move WNW through mid week. $$ Christensen