000 AXPZ20 KNHC 192222 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Tue Jul 19 2016 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 2130 UTC. ...SPECIAL FEATURES... Tropical Storm Darby is centered near 19.9N 136.6W at 2100 UTC, which is about 1070 nm east of Hilo Hawaii. Darby is moving west or 280 deg at 11 kt. The maximum sustained winds have diminished slightly to 55 kt with gusts to 65 kt. The estimated minimum central pressure is 994 mb. Latest satellite imagery shows that the associated convection continues to slowly diminish in coverage and intensity, with scattered moderate convection observed within 120 nm across the northwest semicircle. Darby is forecast to gradually continue to weaken over the next 48 hours, when it will move west of 140W and out of the discussion area. Refer to the latest NHC forecast advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 KNHC for more details. Also, refer to the latest high seas forecast MIAHSFEP2/FZPN03 KNHC for more details on the wave forecasts associated to Darby. Tropical Storm Estelle is centered near 19.0N 119.8W at 2100 UTC, which is about 600 nm sw of the southern tip of the Baja California Peninsula at 1500 UTC Jul 19. Estelle is moving west- northwest, or 285 degrees at 10 kt. The maximum sustained winds remain near 55 kt with gusts to 65 kt. The estimated minimum central pressure is 993 mb. Scattered moderate to strong convection is noted within 150 nm northwest and 120 nm southeast of the center, while scattered moderate convection is elsewhere within 180 nm across the southwest semicircle. Despite computer models continuing to forecast Estelle to strengthen, this has yet to occur, and recent microwave imagery suggests that there is no improvement in the organization of Estelle this afternoon. Therefore, little change in strength is expected overnight and Wednesday morning before a slow and gradual weakening trend occurs as Estelle continues west-northwestward. Refer to the latest NHC forecast advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. Also see latest high seas forecast MIAHSFEP2/FZPN03 KNHC for more details on the wave forecasts associated with Tropical Storm Estelle. ...TROPICAL WAVE... A tropical wave axis along 92W and has been moving w at about 10 kt. Convection remains rather minimal with this wave, and hasshifted westward ahead of the wave to between 94w and 101w. Fresh to strong northerly winds and blowing across and downwind of the Gulf of Tehuantepec in advance of this wave. ..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from Colombia near at 09N79W to 06.5N79W to 10N103W to 13N115W, where it loses identity in broad cyclonic circulation associated with the southeast periphery of Tropical Storm Estelle. Scattered moderate isolated strong convection is noted within 90 nm north and 180 nm s of the trough axis east of 84W. Scattered moderate to strong convection is noted within 270 nm north and 240 nm south of the trough between 89W and 101W, and within 240 nm south of the trough between 101W and 115W. ...DISCUSSION... N of 15N e of 120W: See special features section above for details on tropical cyclone Estelle which will continue westward across the sw portion of the discussion area, with the associated area of tropical storm conditions shifting w of 120W tonight, while the associated seas of 8 ft and greater will shift west of 120W Wed evening. A surface ridge will build in the wake of Estelle from 27N120W to 15N106W late Wed. The gradient ne of the ridge will support moderate to fresh northwest to north winds across the waters n of 29N on Wed, with seas of 4-7 ft building to 5-8 ft on Fri and Sat. A northwest to southeast orientated trough will meander east and west over the Baja California Peninsula, and the northern Gulf of California this week, supporting light and variable winds across the Gulf of California waters through early Fri, then moderate southerly flow is expected Fri afternoon through Sat. The pressure gradient between high pressure over the Gulf of Mexico, and lower pressure across the tropical Eastern Pacific, resulted in strong to near gale force northerly flow across the Gulf of Tehuantepec late last night and early this morning. These conditions will develop again tonight into Wednesday morning, with seas building to 11 ft downstream of the Gulf of Tehuantepec. Weaker northerly flow is expected late in the week as the tropical wave along 92W shifts west of the area. S of 15N e of 120W: Fresh southerly winds, with seas of 7-11 ft, will shift westward across the discussion waters from 13-15N west of 113W through tonight, all in association with tropical cyclone Estelle which is centered just n of the area. Strong e winds will develop across, and just downstream of the Gulf of Papagayo tonight. The resultant easterly wind waves will mix with long period cross equatorial sw swell that will propagate ne across the waters east of 115W this week. Seas to 8 ft are expected across the open pacific waters between 82W and 113W through Thu night when they will subside to less than 8 ft. W of 120W: See special features above for information on tropical cyclones Darby and Estelle that will pass westward through the central portion this week. Combined seas of 7-11 ft primarily due to mixing swell, are expected to surround the large seas near the the cyclones, and cover the waters elsewhere to the north of 10N this week. $$ Stripling