000 AXPZ20 KNHC 010929 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Nov 1 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 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure north of the area over the Gulf of Mexico has weakened. Recent scatterometer data indicates gap winds funneling into the Gulf of Tehuantepec have diminished just below gale force. This is a temporary pause, however, and early morning drainage affects may allow gap winds to regain minimal gale force. Building high pressure and cooler, denser air follow a cold front expected to move through the western Gulf of Mexico late this evening and overnight. This will allow gap winds to increase to occasional strong gales through early next week. Northerly swell will mix with longer period southerly swell to support seas in excess of 8 ft well downstream of the Gulf of Tehuantepec, with peak seas building back to near 20 ft early next week. Please refer to the latest High Seas Forecast issued by the National Hurricane Center at: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. Potential Heavy Rainfall event: A tropical cyclone over the western Caribbean along with a surge of moist southwesterly flow will support the potential for heavy rainfall across portions of Central America into early next week, particularly western Panama and Costa Rica to begin with, then spreading northwestward through mid week. When heavy rainfall occurs, flash flooding and mudslides may be possible. Refer to statements provided by your national meteorological service for more details. ...TROPICAL WAVES... A tropical wave axis has been relocated to near 104W from 02N- 15N, moving W at around 10 kt. Scattered moderate convection is noted from 12N to 16N between 100W and 104W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 10N100W to 12N105W to beyond 10N140W. Scattered moderate convection is noted from 08N to 11N between 110W and 115W. Scattered moderate to isolated strong convection is observed from 10N to 12N between 121W and 123W. Scattered moderate convection from 09N to 11N between 136W and 138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the Special Features section above for details on the Gulf of Tehuantepec Gale Warning. High pressure northwest of Baja California is supporting gentle to moderate northerly breezes across the Mexican offshore waters off Baja California and the Gulf of California. Seas of 2-4 ft prevail in both the open waters and in the Gulf of California. Seas will build to 4 to 6 ft in NW swell in the waters of Baja California through the early part of the week. Elsewhere, little change is expected through the next several days. Gentle winds persist south of Cabo Corrientes outside of the Gulf of Tehuantepec plume, with seas of 4 to 6 ft in mostly southerly swell. Little change is expected. 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 today, with isolated areas of fresh winds ahead and behind of a tropical wave. Large seas are likely off western Guatemala, related to the gale force gap winds in the nearby Gulf of Tehuantepec. Seas reaching 8 ft will mix with building SW swell and spread across the area beyond 120 nm off the coast from El Salvador to Costa Rica by late Tue. Farther south, a combination of fresh SW winds and building SW swell will allow seas to reach 8 to 9 ft off western Panama by tonight. REMAINDER OF THE AREA... High pressure dominates the waters north of 15N. The gradient between the high pressure and lower pressures associated with the monsoon trough will continue to support moderate to locally fresh NE trade winds from the monsoon trough to 20N and west of 115W, for the next several days. Seas are 5 to 7 ft across this region, in a mix of swell and easterly wind waves. Little change is expected through the weekend. A complex low pressure system north of the Hawaiian Islands is forecast to move NE through the weekend. A trailing front may slip southeast of 30N140W by early next week with winds remaining 20 kt or less. Associated seas will build to 8-9 ft behind this boundary on Mon afternoon/evening, impacting the waters north of 25N and west of 137W. South of the monsoon trough, moderate to fresh S to SW winds prevail between 100W and 140W, where seas are 5 to 8 ft. Minor fluctuations in winds and seas are expected across this area through the weekend. Looking ahead, computer models suggest that a broad area of low pressure could become organized by Tue a couple of hundred miles southwest of Clarion Island, and move WNW through the end of the week. There is broad disagreement among the main global models, and confidence remains low on the exact locations and intensity of this low pressure at this time. $$ Christensen