000 AXPZ20 KNHC 150943 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Jan 15 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A ridge across the eastern slopes of the Sierra Madre Oriental of Mexico continue to drive strong to near gale force northerly gap winds across the Tehuantepec region tonight, and will continue throughout the week and into the upcoming weekend. Strong winds during the day to near 30 kt will pulse to minimal gale force at night. Associated seas will build 11 to 12 ft during the periods of gales. Seas in excess of 8 ft continue to reach several hundred miles downstream, mixing with longer period NW swell. Gulf of Papagayo Gale Warning: A persistent ridge across the Caribbean and Central America is supporting strong to near gale force NE to E winds across and downstream of the Gulf of Papagayo region and extending northward to the waters of NW Nicaragua. This pattern will persist through the remainder of the week and into the upcoming weekend, briefly pulsing to minimal gale force overnight and then again Fri night. Seas will build to 10-11 ft each night during the period of peak winds. Please see the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details on these two Gale Warnings. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from northern Colombia near 10N74.5W to 03.5N79W to 07.5N86.5W to 05N93W. The ITCZ continues from 05N93W to 05N109W to 07.5N131W to beyond 07N140W. Widely scattered moderate convection noted within 120 nm N of ITCZ W of 132W, from 09N to 11.5N between 121W and 128W. Scattered moderate isolated strong convection noted from 13N to 19N between 126W and 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above for more on the latest gale force gap wind event in the Gulf of Tehuantepec. Elsewhere, a broad surface ridge will continue to dominate the offshore forecast waters west of Baja California Peninsula during the next several days, supporting moderate to fresh northerly winds W of Baja California through early Thu. NW to N swell is producing seas generally running 6-9 ft N of Punta Eugenia and 5-8 ft across the waters of Baja California Sur. Seas there are forecast to gradually subside through Thu as high pressure builds southeast across the northern forecast waters. Winds and seas will increase abruptly from southern Baja California Sur toward the Revillagigedo Islands Fri into Sat as the high pressure shifts southward ahead of a cold front approaching Baja California Norte. NW to W winds 15 kt or less prevail across the waters from Cabo Corrientes to Puerto Angel tonight. Little change is expected across these waters through early Fri before building the increasing winds and seas across southern Baja shift southeastward to the Cabo Corrientes area on Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see above for more on the latest gale force gap wind event in the Gulf of Papagayo. The pressure gradient responsible for the gale force gap wind events in Tehuantepec and Papagayo regions is also supporting fresh to strong northerly winds across the Gulf of Panama. Fresh northerly winds across the Gulf and downstream to near 04N will increase to strong each night through the morning hours this week, with downstream seas building to 6 to near 8 ft each night. REMAINDER OF THE AREA... A strong surface ridge extends across the northern forecast waters from 1027 mb located offshore of southern California near 34N131W. This high has weakened and shifted SE during the past 12 to 18 hours. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ to the S of the ridge has weakened during the time, and is now producing a modest area of fresh trade winds that roughly covers the waters N of the ITCZ from 07N to 23N W of 115W. Earlier altimeter data indicates seas of 8 to 12 ft across this area in a mix of NW swell and NE trade wind waves. The ridge will weaken gradually through the remainder of the week, which will act to decrease associated winds and seas across this area. To the N of 27N between 117W and 130W, an area of NW to N swell is propagating into these waters with seas of 8 to 9 ft. This swell is forecast to subside by Thu afternoon before new NW swell arrives behind a cold front dropping S into the area. Farther E, seas of 8 to 9 ft will persist along and N of ITCZ east of 120W, due in part to shorter period swell originating from strong gap winds originating from the Gulfs of Tehunatepec and Papagayo. Looking ahead, high pressure will build over the subtropics following a weak cold front moving toward Baja California Norte late in the week. This will support a return to fresh to strong trade winds N of the ITCZ to 20N and W of 120W, with seas building to 8 to 10 ft. $$ Stripling