000 AXPZ20 KNHC 142143 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon May 14 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 2015 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N75W TO 10.5N86W TO 10N89W TO 06.5N106W TO 11.5N114W TO 03N130W, then transitions to ITCZ from 03N130W to beyond 06N140W. Scattered moderate to strong convection is noted within 270 NM N AND 360 NM S OF TROUGH FROM 78W TO 111W, and within 150 NM either side of the trough from 111W TO 122W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A NW to SE oriented high pressure ridge prevails across the offshore waters west of Baja California, producing gentle to moderate northwest winds over those waters. These winds are expected to freshen tonight through Wed and then become fresh to locally strong Wed night as the ridge strengthens slightly. Morning altimeter data indicated that seas are currently in the 5-8 ft range and will diminish to 5-7 ft through late Tue before building slightly on Wed to 6-8 ft in mixed SW swell and fresh NNW wind swell. Gulf of California: S to SW winds of around 15 kt are over the northern sector of the Gulf of California north of 29N this afternoon and will become light and variable tonight. Gentle to moderate NW winds will continue across the remainder of the Gulf through Wed, except for a fresh NW winds along the Mexico coast from 24N to 26N Tue evening through Wed evening. Gulf of Tehuantepec: Light NW to N winds will prevail across the Gulf region this afternoon, then become SW to W tonight as broad and deep layered troughing across the Gulf of Mexico extends further SW into the Yucatan Peninsula and Central America. This trough is forecast to linger across the southern Gulf of Mexico and Central America through most of the week, and will allow for winds across the Tehuantepec region to become variable, and mostly onshore during the day, and offshore at night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Light to gentle winds will dominate the gulf most of the forecast period with seas of 5-6 ft today diminishing slightly on Tue to 4-5 ft in long period SW swell. A strong pulse of cross equatorial SW swell will move into the regional waters beginning Wed, and build seas to 5-7 ft Thu through Sat. Gulf of Panama: Gentle to moderate S to SW winds are forecast during the next several days, with seas of 4-6 ft in long period southerly swell, building to 5-7 ft Wed night through Sat as long period SW swell reaches the coasts of Panama and Colombia. Elsewhere, gentle to moderate southwest winds are expected to the south of the monsoon trough with axis meander roughly along 10N, with light to gentle variable winds north of trough. Seas are forecast to build to 6-7 ft in long period SW swell between Ecuador and the Galapagos Islands beginning on Wed. REMAINDER OF THE AREA... A ridge extends from the NW waters southeastward to near the Revillagigedo Islands. The pressure gradient between the ridge and the monsoon trough and ITCZ to the south is presently weak, and yielding moderate NE to E tradewinds between about 10N and 22N to the west of 110W. Seas across this tradewind belt are expected 7-9 ft this afternoon and will subside to 6-8 ft tonight through Wed. The ridge will shift slightly SE through Wed and increase winds across the tradewind belt ever so slightly before new high pressure shifts SE into N portions of the discussion area Thu and increases tradewinds to fresh to strong. Seas are expected to increase to 7-9 ft Thu into Fri. Decaying NW swell is propagating through the waters north of 20N between Baja California and 126W, where seas are peaking at 7-8 ft. Expect seas W of 117W to subside to less than 8 ft by late tonight and persist through Thu. $$ Stripling