000 AXPZ20 KNHC 250231 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Aug 25 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...SPECIAL FEATURE... Gale Warning...The remnant low of former tropical cyclone Kenneth continues to spin near 28N136.5, but lacks significant deep convection. The estimated minimum central pressure is 1011 mb. The pressure gradient between the low and a subtropical high to the N supports 30 to 35 kt gale force winds within 90 nm of the center except over the SE quadrant, with combined seas of 12 to 15 ft. A large area of strong to near gale winds are observed within 180 nm over the NW and 120 nm over the SE semicircles. The gale center is forecast to move N to near 29N136W on Fri, then weaken to a near gale 30 kt system at 29.5N137W on Fri night. Thereafter, the low will W-NW to near 30.5N137.5W late Sat, and near 31N139W late Sun. The low should weaken to an open trough by Mon night. Please refer to the High Seas Forecast issued under WMO/AWIPS headers FZPN03 KNHC/MIAHSFEP2 for more information. ..TROPICAL WAVES AND TROPICAL LOWS... A tropical wave is analyzed to the N of 05N between 88W and 90W is progressing W at 12 kt. Scattered moderate isolated strong convection is noted to the N of 06N between 86W and 91W. Model guidance is hinting at a surface low developing along this wave during the next few days. A tropical wave is analyzed to the N of 04N along 101W and has been moving W at 8 kt. Scattered moderate isolated strong convection is noted within 240 nm of the wave axis. This wave will likely lose identity over the next day or so. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends W between 09N and 10N across the far SW Caribbean to the Pacific Coast of Costa Rica at 10N85W through a tropical wave at 11N88W to 10N94W, then turns slightly NW through another tropical wave at 12.5N100W to 13.5N118W, then turns SW through an embedded 1010 mb surface low at 10N137W to beyond 10N140W. Scattered moderate isolated strong convection is observed elsewhere within 150 nm either side of a line from 06N82W to 12N110W to 12N140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A NW to SE orientated low level trough will meander E to W across the Baja California Peninsula and Gulf of California through the upcoming weekend with a weak surface low developing intermittently along the trough over the far northern Gulf of California waters. A NW to SE orientated ridge extends across EPAC waters just beyond 250 nm. The pressure gradient will support a moderate NW breeze across the open waters W of the Baja California Peninsula through Sun, except becoming a fresh NW breeze during the evenings within about 90 nm of the Pacific Coast of Baja California. Expect mostly 3 to 6 ft seas forecast throughout these waters this weekend. A weak cold front will move SE across the Baja Peninsula and Gulf of California on Mon night. Gulf of California...light to gentle southerly flow will persist across the Gulf of California this week, except a brief moderate southerly breeze will develop intermittently just S of the low pres over the Gulf waters, roughly along 30N. A moderate NW breeze will follow the cold front on Mon night, which should stall along 28.5N on Mon evening. Gulf of Tehuantepec: Gentle N drainage winds are forecast through the weekend. Strong southwesterly monsoon flow and long period cross- equatorial swell, in the form 7 to 9 ft seas, will arrive across the waters between 97W and 106W at about 250 nm seaward on Sun. By then a surface low may have developed along the N extension of a tropical wave near 14N100W. The low will move NW on Mon and Tue. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate nocturnal drainage forecast to begin on Sun night. Otherwise, light and variable flow is expected N of the monsoon trough through early Mon, while moderate to locally fresh southerly winds are expected S of the monsoon trough axis, with 4 to 7 ft seas by early next week. REMAINDER OF THE AREA... Except as discussed in the special features paragraph, the subtropical ridge extends from 32N132W to near 14N110W, and is accompanied by moderate anticyclonic winds and 4 to 7 ft seas. Moderate to locally fresh southerly winds are forecast S of the monsoon trough on Fri, increasing to a strong breeze from 07N to 10N between 105W and 115W on Sat, and expanding out from 07N to 12N between 100W and 122W on Sat night, with seas building 7 to 9 ft. $$ Nelson