000 AXPZ20 KNHC 080931 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0921 UTC Sat Apr 8 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 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec gale warning...Minimal gale force northerly winds currently across the Gulf of Tehuantepec will diminish later this morning, then diminishing to 20 kt or less by 24 hours. Seas up to 12 ft will gradually subside to less than 8 ft by then as well. The resultant NE swell, in the form of 8 ft seas or greater, will propagate SW mixing with long period cross- equatorial SW swell, reaching as far S as 07N between 96W and 103W, subsiding through tonight. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 05N82W to 04N98W to 03N113W. The intertropical convergence zone axis extends from 04N116W to 05N130W to 03N140W. Scattered moderate and isolated strong convection is within 120 nm either side of the trough between 84W and 88W, and also within 60 nm N of the trough between 92W and 95W. Scattered moderate convection is within 60 nm N of the ITCZ west of 134W. In addition, scattered moderate and isolated strong convection is from 01N to 04N E of 80W, and within 90 nm N of a line from 10N104W to 07N110W to 08N122W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the special features above for the ongoing Gulf of Tehuantepec gale force gap wind event. Broad surfacing ridging extends E across the offshore waters w of the Baja Peninsula, with gentle to moderate n flow expected through the afternoon. A tightening pressure gradient will then increase the NW flow to a fresh to locally strong breeze across the waters offshore of Baja California Norte, with these conditions forecast to spread SE across all waters W of the Baja Peninsula tonight, with seas building to 6 to 9 ft by Sun morning. The gradient will relax on Sun night, with moderate to locally fresh NW flow expected through the middle of next week as seas gradually subside to less than 8 ft on Wed night. In the Gulf of California, light and variable winds are expected through late Sat night, except moderate to fresh southerly nocturnal winds are forecast across the waters to the N of 30N. The low level winds will gradually shift to the NW and increase to a moderate to fresh breeze across the waters N of 26N on Sun. These Nw winds should diminish to a gentle breeze on Mon night. Smoke from agriculture fires over interior Mexico is observed on high resolution satellite imagery across the offshore waters to the N of 10N between 92W and 100W, and is estimated to be locally reducing surface visibility to 3 to 5 nm. Expect improvement in conditions in about 24 hours. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... In the Gulf of Papagayo, fresh to locally strong nocturnal drainage winds expected through Sunday with the resultant NE swell propagating WSW to as far SW as 09N92W this afternoon. In the Gulf of Panama, fresh to locally strong nocturnal northerly flow expected during the overnight hours through the middle of next week, with the strongest winds expected in the next few hours. Elsewhere, light to gentle winds, and combined seas of 3 to 5 ft prevail. REMAINDER OF THE AREA... A cold front extending from 30N123W to 26N130W to 24N140W will sweep E accompanied by a strong wind shift across the discussion waters N of 30N, and a fresh wind shift across the waters from 28N to 30N. Large post frontal NW swell, in the form of combined seas of 8 to 13 ft to the S of 30N, and 10 to 14 ft between 30N and 32N, will propagate E. By Sun night, expect 6 to 9 ft seas across the subtropical waters W of 110W. A batch of NW swell, in the form of 7 to 10 ft seas, will propagate into the far NW portion on Sun night ahead of a cold front reaching from 32N138W to 29N140W late Mon night. Moderate to locally fresh NE trades are expected across the tropics from 05N to 15N W of 110W, with the NE wind waves resulting in an area of 6 to 9 ft combined seas forming across the tropics from 06N to 11N W of 128W this weekend and continuing into early next week. $$ LEWITSKY