000 AXPZ20 KNHC 080906 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 545 UTC Thu Jun 8 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...TROPICAL WAVES... A tropical wave extends from 07N110W to 14N110W. The wave has been moving W at around 10 kt during the past 24 hours. There is no significant convection currently associated with this wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The Monsoon Trough extends W from 10N73W to a persistent surface low centered over NW Colombia near 11N76W, then across the SW Caribbean to end on the Pacific Coast of Costa Rica near 10N86W. The Intertropical Convergence Zone stretches from 08N112W to 07N119W to 08N127W...then resumes from 09N131W to 08N133W to 09N140W. Scattered moderate and isolated strong convection is present within 60 nm either side of a line from 05N86W to 10N89W to 13N89W. Scattered moderate convection is found within 60 nm either side of a line from 07N112W to 06N122W to 09N125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A NW to SE oriented ridge extends from 1019 mb high pressure centered near 25N136W across the EPAC waters just W of the offshore zones. The ridge is being weakened by a cold front that is nearing 30N140W. The relatively weak pressure gradient is maintaining a light to locally moderate NW breeze W of the Baja Peninsula to the N of 25N, and a moderate to fresh W to NW breeze S of 25N. The exception is that fresh to locally strong W to NW winds are expected in response to surface troughing over Baja California Sur during the overnight hours across the coastal waters near Cabo San Lucas early this morning and again tonight. The pressure gradient will tighten tonight W of Baja California Norte as moderate NW winds develop to the N of 25N in response to high pressure building in behind the front. Another round of large NW swell will cause seas to build to between 7 and 9 ft near 32N by sunrise on Sun. The seas will spread S to reach 30N by late Sun night. Gulf of California: Gentle to moderate south winds are expected N of 30N through Sat. Guidance suggests a fresh to locally strong SW breeze from 30N to 31N on Sat and Sun nights, with associated seas peaking around 5 ft. Light to gentle NW winds are anticipated N of 30N on Monday and Monday night. Light and variable winds are expected S of 30N through Monday night. Mexican offshore waters S of 23N including the Gulf of Tehuantepec: Relatively benign conditions are expected through the forecast period. Light to gentle S to W winds and 3 to 5 seas are forecast through Mon night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough crosses the far SW Caribbean just to the N of Panama and Costa Rica. Convection associated with the trough is occurring right along the coastlines of Panama and Costa Rica, as well as about 300 nm to the SW in convergent SW flow. Gentle to moderate westerly winds are expected N of 10N, and moderate to fresh southerly winds are forecast S of 10N through Friday night. Light to moderate southerly flow is then forecast Saturday through Mon night. Combined seas of 5 to 7 ft are expected to build to 6 to 8 ft S of Costa Rica tonight through late Fri. REMAINDER OF THE AREA... A weak 1019 mb surface high is analyzed near 25N136W with a ridge extending SE to near the Revillagigedo Islands. The weak high pressure covers the area north of 15N and west of 115W. Gentle to locally moderate anticyclonic flow is occurring to the south of the ridge to just N of the ITCZ near 10N, while moderate to fresh SW flow is seen N of the ridge ahead of a cold front currently approaching 30N140W. The high will shift E and continue weakening as the cold front reaches a position from near 32N131W to 28N140W by this afternoon. The front will gradually become diffuse as it crosses the north-central and NW portions of the area Friday through Saturday. High pressure following in the wake of the front will cause trade winds to strengthen and become moderate to fresh between 12N and 25N W of 125W Monday through Wednesday. $$ cam