000 AXPZ20 KNHC 210402 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Sep 21 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 0000 UTC surface analysis and satellite imagery through 0345 UTC. ...SPECIAL FEATURES... Tropical Depression Seventeen-E is centered near 16.1N 109.3W at 21/0300 UTC or about 410 nm south of the southern tip of Baja California moving west-northwest at 9 kt. The estimated minimum central pressure is 1005 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Last GOES-17 visible imagery indicates that this system remains poorly organized as evident by its center being exposed as a small swirl of low-level clouds just to north of a large area of deep convection. This convection consists of the scattered moderate to isolated strong type from 10N to 17N between 109W-114W, and of the scattered moderate type intensity from 10N to 16N between 105W-109W. The depression is forecast to maintain its current motion during the next few days and become a tropical storm by Tue. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website- https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Tropical Depression Seventeen-E NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave has its axis along 134W from 03N to a 1009 mb low near 10N134W and north to 18N134W. It is moving westward at 10-15 kt. Scattered showers and isolated thunderstorms are 180 nm either side of the wave from 09N to 12N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to 10N86W to 10N95W and to 13N102W, where it ends. It resumes at 13N116W to 12N126W to low pressure near 10N134W 1009 mb and to 09N136W, where latest scatterometer data indicates that it transitions to the ITCZ to beyond the area at 10N140W. Scattered moderate convection is within 180 nm south of he trough between 84W-85W, within 60 nm south of the ITCZ west of 138W and within 30 nm south of the trough between 134W-138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The gradient induced by weak deep layer ridging between Baja California and 125W is supporting mainly moderate northwest to north winds off Baja California Norte with combined seas to 6 or 7 ft. Winds and seas will diminish some through Tue, except within about 300 nm southwest of the southern tip of Baja California, where much high winds and seas on the periphery of Tropical Depression Seventeen-E can be expected. Farther south, fresh to strong winds will pulse in the Gulf of Tehuantepec region through the next couple of days. Elsewhere, a weak pressure pattern across the region will result in mainly gentle to moderate winds and slight seas. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Gentle to moderate south to southwest winds continue south of the monsoon trough. Elsewhere, gentle winds prevail north of the monsoon trough. Combined seas are currently in the 5-6 ft range in a mix of wind waves and southerly swell. Scattered small clusters of moderate convection are along and just some areas of Central American coast. This activity is more concentrated near Costa Rica. REMAINDER OF THE AREA... A surface trough along 136W from 18N to 24N continues to break up the subtropical ridge and supporting gentle moderate trade winds farther south into the deep tropics. The ridge will gradually build eastward north of 20N through mid week, and trades will strengthen somewhat between the ridge and the monsoon trough. Farther east, seas of 8-9 ft are within an area along the monsoon trough between 105W and 117W. These seas are a result of the fresh to strong southwest to west winds that are occurring in the southern part of the broad cyclonic circulation associated to Tropical Depression Seventeen-E. In addition, persistent long-period southwesterly is present within this area as well further contributing to the build up of these seas. $$ Aguirre