000 AXPZ20 KNHC 010949 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat Jul 01 2017 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 0945 UTC. ...TROPICAL WAVES... A tropical wave is passing through western Panama accompanied by a few tstms. Expect little impact across the EPAC, but the wave may enhance clusters of strong tstms over Costa Rica and Nicaragua through tonight. A tropical wave is analyzed from 07N101W to 15N100W and is moving W at 10 kt. Isolated moderate convection is observed TO THE N OF 10n within 90 nm of the wave axis. A surface low is forecast to soon develop along the wave axis near 11N, and move W to near 11.5N104.5W tonight, near 12.5N105.5W late Sun, and near 13.5N108W late Mon. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends W off the Pacific coast of Costa Rica at 10N86W to 10N97W, then turns SW through a tropical wave near 101W to 07N110W, then NW to near 09N114W where it loses identity. Scattered strong convection is noted along the monsoon trough within 150 nm either side of a line from 07N91W to 10N98W to 09N106W. A trough is analyzed from 07N121W to 14N112W, with isolated strong convection observed within 75 nm either side of the trough. A 1011 mb surface low pressure has weaken to a surface trough from 09N133W to 15N133W with isolated strong convection flaring within 60 nm of the trough. A cluster of scattered moderate convection is noted within 90 nm of 11N125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The remnants of former tropical cyclone Dora are still evident near 20N118W. Otherwise,a NW to SE orientated ridge axis just w of the offshore waters will shift E to near 20N115W tonight. Moderate to locally fresh NW flow, with 3 to 6 ft seas, are forecast this morning, then the gradient will relax with mostly moderate NW flow this evening. By then, long period NW swell in the form of 7 to 9 ft seas, will arrive near 30N120W, continue s to near 28N120W tonight, then subside to 5 to 7 ft late Sun. Gentle to moderate winds, and 3 to 5 ft seas, are expected elsewhere across the open waters N of the Gulf of Tehuantepec through the middle of next week. Gulf of Tehuantepec...Strong northerly nocturnal drainage flow is forecast to begin late tonight, with seas building to about 8 ft. Expect these nocturnal conditions through late next week. Gulf of California...Light to moderate southerly flow is expected across the entire gulf waters through early this afternoon. Expect fresh to locally strong southerly flow across the gulf waters N of 30N this evening through Sun evening, with seas building to 5 ft in the long fetch waters. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo...Moderate to locally fresh nocturnal NE-E winds are then forecast each night through the middle of next week, with seas building to 6 ft. Gentle to moderate southerly winds forecast elsewhere through the middle of next week. The long period cross-equatorial swell, in the form of 5 to 7 ft seas currently across the area s of 10N will subside from the N today with seas of 3-6 ft forecast across the entire area on Sun. REMAINDER OF THE AREA... The remnants of former tropical cyclone Dora are dissipating near 20N118W today. A surface low is forecast to develop along a tropical wave near 11.5N103W today, and move W-NW over the next few days accompanied by gentle cyclonic winds. Otherwise, a NW to SE orientated ridge will extend across the area. Fresh NW to N winds are expected to the N of 30N and E of 130W through late Sun, with 7-9 ft seas. Moderate anticyclonic flow forecast elsewhere to the W of 120W, with 5-7 ft seas. Long period southerly swell, in the form of 7-9 ft seas, currently across the tropical waters S of 09N E of 130W, will continue to subside, with seas below 8 ft on Sun night. $$ Nelson