000 AXPZ20 KNHC 220951 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Sep 22 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 0930 UTC. ...SPECIAL FEATURES... Tropical Storm Lowell is centered near 18.0N 115.6W at 22/0900 UTC or about 430 nm southwest of the southern tip of Baja California moving west-northwest at 11 kt. The estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Enhanced infra-red satellite imagery shows that Lowell remains a sheared system, with no well defined banding features. The imagery reveals numerous moderate to strong convection increasing within 180 nm of the center of Lowell in the SW quadrant. Scattered moderate convection is within 30 nm of 13N116W. An overnight altimeter data pass revealed seas up to 8 ft east of Lowell to near 107W and from 13N to 18N, mainly due to the persistent fetch of fresh to strong southeast to south winds pre-Lowell. Overnight ASCAT data depicted fresh to strong southeast to south winds within the eastern periphery of the broad cyclonic circulation around Lowell. These winds reached as far east as 111W and from 15N to 21N. Lowell is forecast to maintain its current motion through the next day or so, followed by a turn toward the west. Some strengthening is forecast during the next couple of days. 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... The tropical wave previously along 139W has moved west of the area. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to across Panama to 09N84W to 09N92W to 09N100W and to 13N106W. It resumes at 15N119W to 11N131W to 10N140W. Scattered moderate to isolated strong convection is noted from 03N to 09N E of 80W. Scattered moderate convection is within 120 nm south of the trough between 93W-97W and between 103W-107W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The gradient induced by weak deep layer ridging between Baja California and 130W is supporting mainly moderate northwest to north winds off Baja California Norte with combined seas to 6 or 7 ft. Little change is expected with these conditions through, except within about 400 nm southwest of the southern tip of Baja California, where much high winds and seas on the periphery of Tropical Storm Lowell 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. REMAINDER OF THE AREA... The gradient between the subtropical ridge and lower pressure in the tropics is allowing for generally gentle to moderate trades to exist well into the deep tropics. The ridge will build southward some north of 20N and to the west of Lowell through mid-week. Farther east, seas of 8-9 ft are within an area along the monsoon trough between 112W-119W. 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 Storm Lowell. In addition, persistent long-period southwesterly is present within this area as well further contributing to the build up of these seas. $$ Aguirre