000 AXPZ20 KNHC 200331 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Sep 20 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 0315 UTC. ...SPECIAL FEATURES... Broad low pressure is located a couple of hundred nm south- southwest of Manzanillo, Mexico. The surface low center is centered along the monsoon trough near 15N105W, or about approximately 220 nm SSW of Manzanillo, Mexico. Its estimated pressure is 1007 mb. Scattered moderate to isolated strong convection is seen from 11N to 15N between 101W-107W and from 11N to 14N between 107W-112W. Scattered moderate convection is within 180 nm of the low in the NW quadrant. Atmospheric conditions are forecast to be conducive for additional development, and a tropical depression is expected to form early next week while the system moves in a general west-northwestward motion. This system has a medium chance of becoming a tropical cyclone during the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave has its axis along 128W from 02N to 17N. It is moving westward 10 to 15 kt. Only isolated showers and thunderstorms are seen within 60 nm east of the wave from 09N to 10N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A segment of the monsoon trough extends from 11N86W to 13N96W to low pres near 15N105W 1007 mb to 16N111W to 11N120W to low pres near 10N130W 1008 mb and to beyond 09N140W. Scattered moderate to isolated strong convection is from 11N to 15N between 101W-107W and from 11N to 14N between 107W-112W. Scattered moderate convection is within 60 nm south of the trough between 107W-110W, also within 120 nm north of the trough between 131W- 133W and within 60 nm south of the trough between 131W-133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak deep layer ridging is observed between Baja California and 125W is supporting moderate to fresh winds off Baja California Norte with combined seas to 7 ft. An earlier ASCAT indicated 15-20 kt winds mainly north of 30N. Winds and seas will diminish by Sun into early next week as the ridge weakens. Farther south, fresh to strong winds will pulse in the Gulf of Tehuantepec region, starting tonight. 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... A surface trough along 132W from 16N to 25N is breaking up the subtropical ridge and supporting only gentle moderate trade winds farther south into the deep tropics. The ridge will gradually build eastward north of 20N through early next week, and trades will strengthen somewhat between the ridge and the monsoon trough. Farther east, seas are in the 7-8 ft range in an area along the monsoon trough between 105W and 115W. These seas are within 240 nm of the new low pressure centered near 15N105W and are due to a combination of moderate to fresh southwest winds and longer period SW swell. $$ Aguirre