000 AXPZ20 KNHC 270305 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 059 UTC Sun Jan 27 2019 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 0000 UTC surface analysis and satellite imagery through 0245 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: N to NE gale force winds will return to the Gulf of Tehuantepec Sun evening as another cold front barrels into the Gulf of Mexico, then continue until Mon morning. Seas will build to between 10 and 14 feet by around dawn on Mon. Seas 8 feet or greater will fan out to as far W as 09N100W by Mon evening. Winds will diminish and seas will slowly subside after Mon. Another round of building seas and gale force winds is forecast to begin on Tue as the pressure gradient tightens over SE Mexico in response to high pressure surging S along the eastern slopes of the Sierra Madre Oriental mountains behind the next cold front. Please read 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 more details. Gale Warning over the far western portion of the area: Surface low pressure measuring 1008 mb is centered near 20.5N135.5W. Scattered moderate and isolated strong convection is seen within 60 nm of 16N124W and 22N135.5W. Scattered moderate convection is observed elsewhere within 180 nm either side of a line from 10N123W to 22N128W to 27N133W to 27N139W. E to SE 30 to 35 kt winds fan out in the NE quadrant of the low up to 90 nm, with corresponding seas running 10 to 14 ft. Elsewhere E to SE winds of 20 to 30 kt and seas of 9 to 12 ft spread farther out in the NE quadrant up to 330 nm. The low is forecast to weaken and wrap NW around broader low pressure currently centered just W of the area near 17N141W. This will allow winds on the NE side of the low to fall below gale force by sunrise Sun. The low currently near 20.5N135.5W will have weakened into a trough that extends from 28N138W to beyond 26N140W by Sun evening. This area of surrounding swell will slowly diminish in coverage by early on Mon, at which time mixed SE and NW swell will produce combined seas of 8 to 10 ft W of a line from 32N131W to 24N134W to 20N140W. Please read 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 more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 09N75W to 06N81W to 05N90W. The ITCZ continues from 05N90W to 03N106W to 04N129W to beyond 08N140W. Scattered moderate and isolated strong convection is found from 10N to 12N between 121W and 124W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Fresh to strong NW to N winds currently affect the Gulf N of 25N. Winds will change little through Sun afternoon, then diminish to mainly fresh speeds as seas of 5 to 7 ft subside to between 3 and 5 ft. High pressure extending S across the Pacific waters is generating light to moderate N winds west of the Baja California Peninsula. This relatively light wind regime will persist through Tue as the weak ridge stays in place. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE winds will continue across the Gulf of Papagayo tonight, with corresponding seas of 6 to 8 ft. Winds will become moderate to fresh until Mon night, then strong winds can be generally expected through Thu night. Gulf of Panama: Moderate to fresh N to NE winds will generally prevail through Thu night. REMAINDER OF THE AREA... High pressure measuring 1034 mb centered just off the NW coast of Vancouver island near 49N128W ridges S over almost all the forecast waters north of 10N between 110W and 130W. The pressure gradient between the ridge, ITCZ, and broad area of low pressure S of 25N and west of 130W is generating fresh to strong trades between 10N and 20N W of 115W. Seas in this region are running between 6 and 10 ft, highest to the NE of the low currently generating gales over the western waters. Model guidance suggests the area of fresh to strong winds will shift N this weekend in tandem with the low, but gradually diminish in areal coverage tonight and Sun as the low weakens. An extensive area of seas 8 to 11 ft in mixed swell is enveloping the waters elsewhere generally north of 09N and west of 126W. This area of 8 ft seas will retreat NW to N of 26N and W of 137W by Tue morning. $$ CAM