000 AXPZ20 KNHC 232202 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Jun 23 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W TO 09.5N85W to 1010 mb low pressure near 14N106W to 1008mb low pressure near 12.5N115.5W to 09N122W. The ITCZ continues from 09N122W to 08N128W to beyond 11.5N140W. Scattered to locally numerous moderate to strong convection is noted from 04N to 12N east of 97W to the coast of Colombia. Scattered moderate to strong convection is noted within 210 nm either side of the trough between 98W and 120W, and from 04N to 12N between 129W and 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... NW winds have generally diminished across the offshore waters west of Baja California, as a broad surface trough along the W coast of the peninsula has shifted westward and farther away from the peninsula. Afternoon observations along the coast indicate that daytime heating has lead to seabreezes to around 15 kt have developed along the coastlines. Winds will remain variable 10 kt or less through the weekend offshore and be dominated by land and sea breezes near the coast. Southerly winds inside the northern Gulf of California were captured by a midday ASCAT pass and showed 20-27 kt to the north of 28N, while fresh to strong winds are expected elsewhere N of 26N this afternoon. Seas have increased to 6-9 ft north of the Tiburon Basin, and are 4-7 ft south of there. Winds and seas will begin to slowly subside later tonight through late Sunday. Further south, long period cross-equatorial SW swell continues to gradually build across the regional waters and will affect the waters from central Baja California to Central America through Monday. 5 to 7 ft seas off of Southern Mexico today will build to 6-8 ft by Sun morning before slowly subsiding late Sun night and Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will meander between 09N and 13N the next several days. Light to gentle winds will prevail north of the monsoon trough, with gentle to moderate S to SW winds expected south of the trough axis. Long period cross-equatorial SW swell has moved into the regional waters and will gradually build across southern forecast waters through Sun, and peak near t 7- 9 ft tonight, then will gradually subside Sun through Mon. A tropical wave across Central America along about 90W will continue westward through Mon and maintain active convection near and to the south of the monsoon trough during this time. REMAINDER OF THE AREA... High pressure north of the area centered near 35N141W extends a ridge SE to near the Revillagigedo Islands. To the S and SE of the ridge, moderate to fresh NE to E winds prevail west of 130W with seas generally ranging between 5 to 7 ft. Gentle to moderate N to NE winds dominate the remainder of the basin north of the monsoon trough and west of 120W. The high pressure center is forecast to shift NW and reorganize, while the weak trough offshore of Baja California drifts west to near 120W through Mon. This will gradually freshen winds N of 25N and to the west of 125W, producing NE winds of 15-25 kt, and building seas of 7- 10 ft across the northern waters. Typical northerly swell generated offshore of California is propagating into the northern waters today, and will build seas modestly to 8 ft north of 28.5N between 122W and 129W late tonight before seas subside to 6-7 ft Sun afternoon. The cross- equatorial southerly swell is also moving through the tropical waters south of 20N and west of 120W today, and will maintain seas 5-7 ft there through Mon. A low pressure centered near 12.5N115.5W embedded along the monsoon trough has an estimated pressure of 1008 mb. Model guidance shows this low drifting northward with a gradual increase in intensity through the weekend. Active thunderstorms will continue in the vicinity of this low through early next week before the low moves across cooler waters and begins to weaken considerably Tue. A 1010 mb low pressure is near 14N106W generating scattered moderate to strong convection from 11N to 17.5N between 99W and 110W. Global models indicate that this low will linger across this area through at least Mon and continue to generate active convection. $$ Stripling