000 AXPZ20 KNHC 172116 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Oct 17 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Tropical Depression Eighteen-E is centered near 10.1N 126.5W at 17/2100 UTC moving W at 2 kt. Estimated minimum central pressure is 1005 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Scattered moderate to strong convection is noted within 240 nm in the SE semicircle and within 150 nm in the NW semicircle. The depression is forecast to strengthen to a minimal tropical storm by Fri, while not moving much through the next few days. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC for more details. Heavy Rainfall Event for southern Mexico: Moderate to fresh strong southwesterly monsoonal flow under a very moist and unstable atmosphere will continue to advect abundant moisture over southern Mexico through tonight. As a result, heavy rainfall is possible over portions of southern Mexico from Chiapas to Jalisco. These rains could cause flooding and mudslides, especially in mountainous areas. Strong gusty winds are possible in and near showers and thunderstorms. Please monitor products from your local or national meteorological service for more details on this event. ...TROPICAL WAVES... The axis of a tropical wave is near 79W, from near the Colombia/Ecuador border to eastern Panama, moving W at around 15 kt. Scattered moderate convection is noted N of 05N between the coast of Colombia and 81W, and also from 02N to 05N between 79W and 83W. The axis of a tropical wave is near 120W from 02N to 15N, moving W at 5-10 kt. Scattered moderate convection is noted from 08N to 10N between 118W and 120W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from the coast of Costa Rica near 10N86W to 16N97W to low pressure near 14N114W to 10N123W, then resumes near 10N131W to 10N140W. Scattered moderate and isolated strong convection is noted within 210 nm S of the monsoon trough between 92W and 104W, and also from 06N to 13N between 130W and 135W. Similar convection is noted within 120 nm in the W quadrant of the low near 14N114W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for more details about a heavy rainfall event over southern Mexico. A 1009 mb low pressure area is located about 75 nm S of Cabo Corrientes. This low has scattered moderate and isolated strong convection within 270 nm in the S quadrant. This low is currently forecast to dissipate by the end of the week. Moderate to fresh SW monsoonal flow and wave heights of 6-8 ft will remain to the S of the monsoon trough in the Gulf of Tehuantepec zone and vicinity through the end of the week. A ridge will build 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 wave heights reaching a range of 10-14 ft, spreading SE reaching the Revillagigedo Islands by Sat night and continuing through Sun night. This swell will gradually decay early next week. Gulf of California: The pressure gradient will tighten across the region early next week as high pressure W of the area shifts NE. This will allow for NW flow to freshen in the northern and central Gulf. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate SW to W winds will change little through Fri. SW swell will begin to propagate into the southern waters on Fri. The swell will spread NE through the weekend, decaying early next week. REMAINDER OF THE AREA... Please read the Special Features section for more details about Tropical Depression Eighteen-E. A dissipating cold front extends from near Catalina Island, California through 30N134W to 28N137W. This front is ushering in a large set of NW swell with seas currently 8-12 ft N of the boundary to 32N. The front will completely dissipate tonight while the NW swell continues to propagate to the SE. Seas will peak around 10-14 ft N of 24N between 118W and 128W Fri night into Sat, aided by fresh to strong winds which will spread southward from off the southern California coast. The edge of seas of 8 ft or greater will reach to 10N and W of 110W by Sat night into Sun. This swell will gradually decay early next week along with the fresh to strong winds which will diminish. Otherwise, a weak ridge extends across the waters S of the dissipating cold front and N of the monsoon trough. Mainly moderate to fresh trades are noted underneath the ridge as supported by recent scatterometer data, except for a small area of fresh to strong winds near 140W in the wake of a now departed surface trough. These conditions near 140W will shift westward tonight as the trough continues away from the area. $$ Lewitsky