000 AXPZ20 KNHC 031515 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1515 UTC Fri Mar 3 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURE... Strong high pressure over the southern United States and Gulf of Mexico is forcing a gap gale wind event over the Gulf of Tehuantepec. A 30 to 40 kt gale is forecast to persist through tonight, then decrease to minimal gale through Sunday morning. The high will shift east of the Gulf basin by later Sunday which will allow the gap winds to decrease below gale force. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFEP2/FZPN03 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ axis extends from 04N89W to 03N110W to 05N130W. No significant convection is noted. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong high pressure over the Gulf of Mexico is forcing a Tehuantepec gale. Please refer to the special features section above for more details. The combination of strong high pressure over the inter- mountain region of the U.S. and troughing extending from northwest to southeast just east of the Gulf of California is generating strong northwest winds over the Gulf of California. Winds and seas will quickly diminish and subside through late this afternoon as the high to the northeast weakens and shifts eastward. Elsewhere, light to gentle winds and 4 to 6 ft seas will prevail across the offshore waters of Mexico through Sunday. High pressure building behind a cold front crossing the northeast and north- central waters Monday will bring fresh to locally strong north to northwest winds along with seas as high as 9 ft to the waters along the Baja coast Monday through Tuesday night. The high will also support strong northwest winds over the Gulf of California Monday night through Wednesday with seas to 8 ft. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... High pressure north and east of the region will continue to force fresh to strong northeast winds through the Gulf of Papagayo, spanning from about 08N to 13N and as far west as 92W the next several days, with the strongest winds occurring late night through the morning hours. Seas will build to 8 to 10 across the area, with the swell propagating westward while merging with large swell from the Gulf of Tehuantepec winds. Over the Gulf of Panama...winds will freshen each night before diminishing during the late afternoon hours through Monday. A period of fresh to strong winds and seas to 8 ft will occur Saturday through Sunday night. Elsewhere...light to gentle breezes and seas of 4 to 6 ft will persist through early next week. REMAINDER OF THE AREA... The pressure gradient between 1030 mb high pressure centered to the north of the discussion area near 35N136W and lower pressure in the vicinity of the ITCZ is still maintaining fresh to strong northeast to east winds from about 12N to 17N, west of 134W with seas of 8 to 9 ft covering a broader area from about 05N to 25N west of 125W. The winds and seas will diminish and subside through Saturday night as high pressure weakens in response to an approaching cold front. By Sunday night, north swell following in the wake of the cold front will cause seas to build to between 8 and 10 ft over the far northern waters north of 28N west of 125W. Wave model guidance shows this swell propagating SE and spreading across the majority of the waters north of 05N by Tuesday. $$ LATTO NATIONAL HURRICANE CENTER