000 AXPZ20 KNHC 050222 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Nov 05 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 0215 UTC. INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends SW from the Pacific coast of Nicaragua at 11N86W through an embedded 1011 mb surface low at 09N96W to 11N118W where it loses identity. Scatterometer data indicate that an ITCZ forms near 11N123W and extends W-SW to beyond 10N140W. Scattered moderate isolated strong convection is observed within 45 nm either side of a line from 07N81W to 10N86W, within 150 nm either side of a line from 09N91W to 09N98W, within 120 nm of 07N114W and within 60 nm either side of a line from 11.5N136W to 10N140W. A trough is analyzed across the tropics from 19N121W to 12N120W with scattered moderate isolated strong convection observed within 75 nm either side of a line from 21N117W to 16N116W to 13N121W. A trough is analyzed from 30N125W to 21N129W with scattered moderate convection noted within 60 nm E of the trough axis. A trough is analyzed from 30N129W to 22N139W with scattered moderate convection noted S of 26N within 180 nm W of the trough axis. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface high will meander near 30N120W overnight, then shift N of the area midday on Sun leaving a N to S orientated ridge meandering from near 32N120W to 17N110W through the middle of the week. Gentle to locally moderate northerly flow, and 3 to 5 ft seas, are forecast across the EPAC waters W of the Baja Penisula through Sun, with model guidance then suggesting that the pressure gradient will tighten a little supporting moderate to locally fresh NW flow beginning on Sun night. Gulf of Tehuantepec: Strong to near gale force northerly drainage flow, with seas to 10 ft, is expected through early Mon, then the pressure gradient will relax briefly on Mon afternoon supporting a fresh N breeze. Strong N-NE flow will resume on Mon evening, with strong northerly pulses then continuing through Wed. Near gale conditions are expected on Wed night and Thu, further increasing to minimal gale force on Thu evening, with seas then building to 12 ft. Gulf of California: Moderate to locally fresh NW flow expected across the gulf waters S of 26N overnight. These conditions will spread N across the waters S of 29N on Sun, and continue through mid week, with an embedded narrow swath of strong NW winds forecast from 25N to 27N on Wed. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to fresh NE drainage winds, with 4 to 6 ft seas, are forecast during the overnight hours beginning on Mon night. Light and variable winds, and 2 to 4 ft seas, are expected elsewhere to the N of the monsoon trough, while moderate to locally fresh southerly winds, and 4 to 7 ft seas, are forecast S of the monsoon trough through mid week. REMAINDER OF THE AREA... A nearly-stationary frontal trough is analyzed from 30N130W to 24N140W. Strong to near gale NE winds, with 8 to 13 ft seas, are observed W of a line from 32N133W to 27N140W. The trough will drift W on Sun. A surface low will develop along the trough near 27N131W late Sun with strong NE winds continuing across the forecast waters within about 180 nm over the NW semicircle of the low through Mon. The low will drift S on Tue with the pressure gradient relaxing, and winds diminishing to 20 kt or less and seas less than 8 ft. A new round of NW swell in the form of 8 to 10 ft seas will arrive along 32N W of 135W on Tue night, with the eastern edge of these conditions reaching a position from 32N120W to 21N140W on Thu night. $$ Nelson