000 AXPZ20 KNHC 210209 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0209 UTC Tue Jun 21 2016 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 0200 UTC. ..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N78W to 08N90W to 11N100W to 08N113W to 11N121W. The intertropical convergence zone axis extends from 09N124W to 07N140W. Scattered moderate convection is within 240 nm south of the monsoon trough to the east of 84W and also between 90W and 98W. Similar convection is from 11N to 14N between 102W and 107W, and within 180 nm either side of the monsoon trough between 109W and 119W. ...DISCUSSION... North of 15N east of 120W: A surface trough extends across the northern Gulf of California toward Punta Eugenia on the Baja California peninsula. Another surface trough extends from 32N117W to 27N117W to 16N118W. Gentle to moderate flow prevails west of the Baja California peninsula on either side of the troughing, with seas of 4 to 7 ft off Baja California Norte extending to 120W, and 4 to 6 feet elsewhere. Long period southwest swell will move to the north of 15N through the early part of the week. Mainly moderate southerly flow will prevail in the Gulf of California, occasionally pulsing to fresh to the north of 29N. The pressure gradient between high pressure building over the Gulf of Mexico and lower pressures within the monsoon trough over the eastern North Pacific will help to support strong gap wind flow through the Gulf of Tehuantepec, commencing later tonight. The mix of shorter period wind waves from the gap winds with the longer period southwest swell will result in areas of confused seas in and downstream of the Gulf of Tehuantepec. In addition, the swell will bring the potential for hazardous surf along exposed areas of the coast of Mexico through the entire week. South of 15N east of 120W: Mainly moderate monsoonal flow prevails to the south of the monsoon trough, while gentle to moderate northeasterly trade winds prevail to the north of the monsoon trough, except locally to fresh downwind of the Gulf of Papagayo. Southwesterly swell is in the 5 to 8 foot range is within 250 nm offshore, and in the 7 to 10 foot range beyond 250 nm offshore. A new set of long period southwesterly swell moving into the area will build wave heights to 6 to 9 feet across the entire area through tonight, then to 7 to 10 feet Tuesday and Tuesday night through the end of the week. This swell will create the potential for hazardous surf along exposed areas of the Central American coast. Seas will finally start to subside Friday and Friday night from south to north. West of 120W: A surge of northerly winds off the coast of Southern California is pushing south of 32N, and will bring fresh winds as far south as 24N between 120W and 132W, with seas of 7 to 9 feet through mid week. These conditions will persist through the end of the week. Elsewhere the pressure gradient between high pressure anchored to the north of the region, and low pressure within the monsoon trough and in the vicinity of the ITCZ is supporting moderate to fresh winds, with combined seas in the 4 to 7 foot range, except 7 to 9 feet near the Equator. The ridge will prevail in the northern waters during the next few days with these general conditions persisting. $$ JLewitsky