000 AXPZ20 KNHC 151600 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1508 UTC Sat Feb 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 1200 UTC surface analysis and satellite imagery through 1450 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: N to NE gales of 30 to 35 kt linger over the Gulf of Tehuantepec. Resultant wave heights remain between 10 and 16 ft this morning The ridge extending S along the Sierra Madre Oriental of Mexico supporting these winds has begun shifting E. This has resulted in winds diminishing from strong to minimal gale force. Winds will falling below gale force by dawn on Sun. Wave heights downstream of the area are expected to subside below 8 ft by Wed morning. Eastern North Pacific Gale Warning: A mid to upper-level low centered near 20N135W is slowly shifting SSW. The low has induced a surface trough that extends from 08N134W to 15N130W. The trough is expected to further develop and cause the pressure gradient between it and high pressure over the northern waters to increase. This will result in strengthening trades between 10N and 20N and high seas between 125W and 135W this weekend. Winds will peak around 35 kt between 125W and 135W Sun morning with wave heights building to between 10 and 14 ft. The upper low will also create very unstable atmospheric conditions and trigger widespread squalls and thunderstorms across this region. Conditions are expected to improve early next week as the surface trough loses upper-level support, drifts west and gradually weakens. Refer to the latest High Seas Forecast FZPN03 KNHC/HSFEP2 issued by the National Hurricane Center, and the website https://www.nhc.noaa.gov/text/MIAHSFEP2 for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from 11N74W to 03N80W to 05N84W to 04N89W. Surface troughs that segment the ITCZ extend from 08N134W to 15N130W and from 03N115W to 09N111W. Accordingly, the ITCZ is divided into 3 segments from 04N89W to 03N100W to 08N108W, from 06N118W to 08N131W and from 07N136W to beyond 06N140W. The surface troughs segmenting the ITCZ are focusing scattered moderate and isolated strong convection within 360 nm either side of a line from 10N110W to 16N133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on the latest ongoing Gulf of Tehuantepec gale wind event. Strong high pressure centered NW of the area near 37N135W ridges SE to near Las Tres Marias. A generally weak pressure gradient prevails across the waters north of 24N. This setup will maintain gentle to moderate N winds over the nearshore waters of Baja and across the Gulf of California. The strongest winds are expected from the entrance of the Gulf to Cabo Corrientes today through early Sun. Elsewhere, light to gentle winds will continue over the remaining Mexican offshore waters, except for the Tehuantepec region as described above. Seas over these waters are in the 4-6 ft range, except lower wave heights of 2-4 ft inside the Gulf of California. Little change in these conditions is expected through Sun morning. The ridge will build SE across the region, increasing the pressure gradient and the winds over the central and southern Gulf of California to fresh speeds the Sun and Mon. Gentle to moderate N winds will then dominate the region of Baja and the Gulf through the middle of next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong to near gale force NE to E winds will continue over the Papagayo region through Wed night. This will generate a large area of fresh to strong winds and build seas to 8-11 ft. ENE swell generated by this gap wind event will combine with swell propagating S from the Tehuantepec region, and merge to create high and confused seas across the offshore waters of Guatemala and El Salvador through Mon night. Fresh to strong N winds occurring across the Gulf of Panama and extending S to around 04N will also change little through Wed night. Wave heights across these waters will remain between 6 and 8 ft. REMAINDER OF THE AREA... A strong ridge anchored by a 1031 mb high N of the area near 37N135W is supporting moderate to fresh trades N of 10N and W of 115W, except for fresh to strong trades from 12N-20N W of 125W, where the aforementioned surface trough has already developed. Seas across this area are already in the 8-10 ft range, generally in mixed NE wind waves and NW to N swell. Very active convection is expected to continue across this area through late Sun as the upper level low slowly digs SSW over the region and supports the surface trough. Otherwise, see the Special Features section above regarding the developing gale over the tropical waters W of 125W on Sun. $$ CAM