000 AXPZ20 KNHC 180304 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 303 UTC Fri May 18 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N85W to 1010 mb low pressure near 11N122W to 08N130W. The intertropical convergent zone continues from 08N130W to 06N140W. Scatterer moderate convection is noted from 05N to 10N between 90W and 115W. Scattered moderate to isolated strong convection is noted from 10N to 15N between 110W and 125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Moderate to fresh northwesterly winds persist off Baja California between a 1025 mb high pressure centered west of the area and lower pressure over northwest Mexico. Seas are 6 to 8 ft off Baja California Sur with a component of SW swell, and 5 to 7 ft elsewhere. Winds may briefly increase to 25 kt late today between Cabo San Lazaro and Punta Eugenia as a middle to upper level trough moving through southern California through Sat clips Baja California Norte and the northern Gulf of California. Moderate northwesterly winds will persist off the coast of Baja California thereafter through Tue. However, seas are forecast to build to 8 ft in long period SW swell off Baja California Norte Mon morning through Tue morning. For the Gulf of California, fresh to strong westerly gap winds will pulse over the northern Gulf of California tonight in the wake of a weak trough moving across the region. Variable light to gentle winds with seas to 4 ft will dominate elsewhere through Tue. Weak northerly flow with seas of 5-7 ft in SW swell is along the remainder of the coast of Mexico. Seas forecast to increase to 8 ft Mon morning and subsiding Tue. 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 the entire forecast period as weak pressure will prevail across Central America. Seas of 4-7 ft are forecast over the Gulf and nearby waters through Tue. Gulf of Panama: Gentle to moderate S to SW winds are forecast through Tue with seas of 4-6 ft in long period SW swell, building to 5-7 ft on Mon as the swell reaches the coasts of Panama and Colombia. Expect big waves along those coasts. Elsewhere, gentle to moderate SW winds are expected to the south of the monsoon trough with light to gentle variable winds north of trough as a weak pressure pattern remains over Central America. Seas are forecast to build to 6-7 ft in long period SW swell between Ecuador and the Galapagos Islands tonight, continuing through the weekend. Wave mode guidance indicates that these seas will build to 8 ft Sun night and will subside on Tue. REMAINDER OF THE AREA... A 1025 mb high is centered near 31N137W, with a ridge axis extending southeastward to Baja California Sur offshore waters. In the tropics, a 1010 mb low pressure is centered along the monsoon trough near 11N122W with scattered heavy showers and thunderstorms are within 210 nm of northwest semicircle of low pressure. Gentle to moderate northerly winds are noted north of 20N, with moderate to fresh trade winds from the monsoon trough/ITCZ and 20N, although fresh to strong NE winds are possible north of the low pressure area. The low pressure will drift westward and change little through the next couple of days. TOGA/TAO buoys are showing light to moderate southerly flow into the monsoon trough. Altimeter satellite date is also showing southerly cross- equatorial swell of 6 to 8 ft south of the monsoon trough between 105W and 125W. This will decay through the next couple of days, but reinforcing SW in excess of 8 ft will start to move into the region in the next the 36 hours. $$ Christensen