000 AXPZ20 KNHC 251609 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Oct 25 2018 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 1800 UTC. ...TROPICAL WAVE... A tropical wave is analyzed N of 03N along 98W-99W moving W 10 kt. Isolated clusters of moderate to strong convection are flaring along the monsoon trough near the wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N75W TO 09N87W TO 06N107W TO LOW PRES 14N118.5W TO LOW PRES 11N123.5W, where scatterometer winds indicate a transition to an ITCZ, which then continues W to 09.5N134W to beyond 09.5N140W. Scattered moderate isolated strong convection is observed within 180 nm over the NE quadrant of the surface low at 14N118.5W. Scattered moderate to strong convection is observed within 180 nm over the E and SW quadrants of the surface low at 11N123.5W. Scattered moderate to strong convection is noted from 05N to 08N between 77W and 83W, and within 150 nm of the ITCZ W of 125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A modest ridge extending from the waters W of 120W extends SE to near the Islas Revillagigedo this morning and will prevail across the offshore waters through the upcoming weekend. This pattern will produce light to gentle anticyclonic flow around the ridge, except gentle to locally moderate NW flow is expected W of the Baja California Peninsula through Fri night. Strong N winds and 8 to 15 ft seas, will propagate S into the waters N of 29.5N E of 120W on Mon night. Gulf of California: Light and variable winds will become a gentle NW breeze by Fri morning, and a moderate NW breeze on Fri night, with little change then through Sat night. Gulf of Tehuantepec...Gentle onshore flow is forecast during the daylight hours, and gentle to locally moderate offshore drainage expected nocturnally through late Sat. Model guidance suggests the next strong to near gale northerly wind event will begin on Sat evening, with gale force conditions possible on Mon evening through Tue morning with seas building to 14 ft downstream of the gulf waters. Guidance indicates the northerly winds will diminish to 20 kt or less, and seas will subside to less than 8 ft late Wed night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo...Fresh NE flow, with 5 to 7 ft seas, will diminish to a moderate breeze this afternoon with little change through late Sun when fresh NE flow is forecast to resume, and then continue through late Mon. Light to gentle variable winds, and 3 to 6 ft seas are forecast elsewhere N of the monsoon trough through early next week, while moderate southwesterly monsoonal flow, with 5 to 7 ft seas, is forecast S of the monsoon trough. REMAINDER OF THE AREA... A 1023 mb surface high meandering over the far NW waters near 31N131W is forecast to shift NE to near 32N133W by early Fri, and lift N of 32N on Fri night. Mixing swell will result in a large area of 7 to 9 ft seas N of the ITCZ and W of 130W through Sat morning. NW swell in the form of 7 to 9 ft seas, will reach along 28N between 122W and 130W on Fri, then subside to less than 8 ft Fri night. A 1009 mb low near 14N118.5W along the monsoon trough will move WSW for the next few days, and pass south of the ridge to produce a small area of 20-25 kt ne winds across the NW quadrant of the low, where seas will remain around 8 ft. The low will likely dissipate over the weekend. A 1011 mb surface low analyzed along the monsoon trough at 11N123.5W is expected to also move WSW and lose identity within the trough by Sat. Active convection near this low this morning will continue through this evening. A cold front will reach a line from 32N137W to 29N140W on Sat night followed by 8 to 10 ft seas in long period NW swell. Although the front will wash out on Sun, the associated post- frontal NW swell will propagate E across the discussion area reaching a line from 32N127W to 17N140W on Sun night, and reach from the northern Baja California Peninsula to near 10N140W on Mon night, just as a surge of strong northerly winds accompanied by 10 to 15 ft seas, moves into the waters N of 29.5N between 118W and 125W. $$ Stripling