000 AXPZ20 KNHC 042150 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Nov 04 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 W between 09N and 10N from the Caribbean coast of Colombia at 10N75W to the Pacific coast of Costa Rica at 09N84W TO 13N117W TO 09N124W where scatterometer data indicates that an ITCZ forms and extends W-NW to beyond 10N140W. Scattered moderate isolated strong convection is observed within 150 nm either side of a line from 05N78W to 09N90W to 09N112W, and within 45 nm either side of lines from 08N122W to 09N128W and from 11N136W to 10N140W. A trough is analyzed from 27.5N121W to 21N128W with scattered moderate convection noted within 45 nm either side of the trough. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface high will meander near 30N120W through early Sun, then shift N of the area leaving a N to S orientated ridge meandering from 30N120W 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 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. Strong N-NE flow will resume on Mon evening, with strong northerly pulses continuing through Wed. Near gale conditions are expected on Wed night and Thu, 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 this evening. These conditions will spread N across the waters S of 29N on Sun, and continue through mid week, with a 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 frontal trough is analyzed from 30N130W to 24N140W. Strong 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 on Sun night with strong NE winds continuing across the forecast waters within about 180 nm over the NW semicircle of the low. 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