000 AXPZ20 KNHC 071553 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Jun07 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 1200 UTC surface analysis and satellite imagery through 1545 UTC. ...TROPICAL WAVES... A tropical wave extends from 07N96W to 15N96W with an embedded 1008 mb surface low along the wave at 11N96W. This wave has been moving w at 15 to 20 kt. There is no significant convection associated with this wave at the moment. A tropical wave extends from 07N106W to 17N107W with an embedded 1009 mb surface low at 11.5N106W. The wave has been moving w at 10 kt. Scattered moderate isolated strong convection is currently observed within 180 nm over the nw quadrant of the low. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The Monsoon Trough begins at a persistent surface low over nw Colombia near 09.5N74W, and extends sw across the Gulf of Panama to 08N80W, then turns nw over and along to Pacific coast of Panama and Costa Rica to 10N86W, then turns w through surface lows at 11N96W and 12N106W, the drops sw to 07N110W where scatterometer winds indicate that the ITCZ forms, and continues nw through an embedded trough at 10N129W, then turns sw to beyond 07N140W. The embedded trough extends along 06N130W to 14N127W, but is only accompanied by a few moderate showers. Scattered moderate to strong convection is noted within 150 nm either side of a line from 05N77W to 11N89W, and extends just inland where locally heavy rainfall has been occurring. Another cluster of scattered moderate isolated strong convection is observed along the Pacific coast of Mexico within 60 nm either side of a line from 15N97W to 17N102W. Similar convection is observed along the ITCZ within 90 nm either side of a line from 08N102W to 06N117W to 08N126W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A nw to se orientated ridge extends across the EPAC waters just w of the offshore zones, with the associated pressure gradient 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 locally strong w to nw winds expected during the overnight hours across the coastal waters near Cabo San Lucas tonight and on Thu night. The pressure gradient will tighten on Thu night with moderate nw flow developing to the n of 25N. Another round of large nw swell in the form of 7 to 9 ft seas will arrive along 32N at sunrise on Sun and spread s to along 30N on Sun night. Gulf of California: Gentle to moderate southerly flow expected n of 30N through Sat with guidance suggesting a fresh to locally strong sw breeze from 30N to 31N on Sat and Sun nights, with seas building to about 5 ft. Light and variable winds are expected s of 30N. Mexican offshore waters s of 23N including the Gulf of Tehuantepec: Light to gentle s to w flow, and 3 to 5 seas forecast through Sun night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough extends e to w across the area between 08N and 11N accompanied by considerable convection. Gentle to moderate westerly winds expected n of 10N, and moderate to fresh southerly winds forecast s of 10N through early Fri. Light to moderate southerly flow then forecast through Sun night. Combined seas of 5 to 7 ft are expected to build to 6 to 8 ft s of Costa Rica on Thu night through late Fri. REMAINDER OF THE AREA... A 1021 mb surface high is analyzed at 29N132W with a ridge extending se to near 10N114W. Gentle to locally moderate anticyclonic flow is observed s of the ridge to along 10N. Moderate to fresh sw flow is forecast n of the surface high today. The high will shift s tonight allowing a cold front to move into the area and reach from 32N131W to 28N140W on Thu. The front will wash out from near 32N120W to 26N140W on Fri night. $$ Nelson