000 AXPZ20 KNHC 170141 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Oct 16 2019 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 0000 UTC surface analysis and satellite imagery through 0130 UTC. ...SPECIAL FEATURES... Heavy Rainfall Event for southern Mexico: A broad area of low pressure located inland over the Mexican states of Oaxaca and Guerrero will spread heavy rainfall over portions of those Mexican states as well as Michoacan, Colima, Jalasco and Nayarit through Thursday. These rains could cause flooding and mudslides, especially in mountainous areas. Please monitor products from your local or national meteorological service for more details. ...TROPICAL WAVES... The axis of a tropical wave is near 118W/119W, from 04N to 16N, moving W at 5-10 kt. Scattered moderate convection is noted from 09N to 11N between 119W and 122W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northern Panama near 09N80W to across Costa Rica to along the Pacific coasts of Nicaragua to El Salvador, Guatemala and Mexico to 17N96W to 11N102W to low pressure near 11.5N125.5W to 13N135W. Scattered moderate and isolated strong convection is noted from 08N to 11N between 85W and 87W, and also within 240 nm S of the monsoon trough between 91W and 110W and from 07N to 10N between 126W and 133W. Scattered moderate convection is noted from 04N to 08N between 80W and 86W. In additional, numerous moderate and scattered strong convection is noted from 14N to 20N between 97W and 107W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for more details about a heavy rainfall event over southern Mexico. Moderate to fresh SW monsoonal flow and seas of 6-8 ft will persist S of the monsoon trough in the Gulf of Tehuantepec zone through the end of the week. Elsewhere, a ridge will build through the week across the Baja California offshore waters producing mainly a moderate NW to N wind flow. A set of large NW swell will propagate into the Baja California Norte offshore waters by the end of the week with seas of 8-12 ft, spreading SE and reaching the Revillagigedo Islands by Sat night and continuing through Sun night. This swell will gradually decay early next week. Looking ahead, the pressure gradient across the Gulf of California region will tighten early next week. This will allow NW flow to freshen, locally strong in the northern and central Gulf. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh SW monsoonal flow continues to support 6-8 ft seas in the El Salvador and Guatemala offshore waters. These winds and seas will diminish and subside through Thu. Otherwise and elsewhere, mainly moderate SW-W winds will prevail along with 4-7 ft seas. REMAINDER OF THE AREA... A ridge dominates mainly the waters N of 19N W of 120W. Scatterometer data indicates mainly gentle to moderate trades across this area under the ridge. Just to the S of the ridge, a trough is over the far W central waters along 138W from 11N to 19N. Associated scattered moderate and isolated strong convection is noted from 06N to 16N between 137W and 140W. This trough will drift westward through Thu with an area of fresh to strong trades and seas of 8-9 ft, gradually pushing W of 140W through Thu night. A nearly stationary 1012 mb low pressure area is embedded in the monsoon trough near 11.5N125.5W. Scattered moderate and isolated strong convection is noted within 120 nm in the SE and S quadrants of the low. Also, an area of fresh to locally strong winds and seas to 8 ft is within 60-120 nm NW quadrant of the low center. This low is forecast to linger in the same general area through the week with some increase in winds and seas in the vicinity. A cold front will is approaching the discussion area near 30N140W. The front will usher in a set of long period NW swell, with seas of 8 to 10 ft affecting the waters N of 28N W of 130W by Thu morning. This swell will continue to propagate SE-S through the end of the week, with seas of 8 ft or greater likely covering the waters N of 20N W of 110W, and from 10N to 20N W of 115W by Sat. The swell will slowly decay from NW to SE by the end of the upcoming weekend and into early next week. $$ Lewitsky