000 AXPZ20 KNHC 150903 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 622 UTC Tue Aug 15 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 0830 UTC. ...TROPICAL WAVES... A tropical wave extends from 06N97W across the Gulf of Tehuantepec to 18N94W. The wave is moving W around 15 kt. Scattered moderate and isolated strong convection is present from 06N to 16N between 93W and 100W. A tropical wave extends from 06N104W to 1008 mb low pressure near 11N104W to 15N104W. The wave and low are drifting WNW at less than 5 kt. Scattered moderate and isolated strong convection is found from 05N to 14N between 100W and 108W. Both the low and wave are expected to continue on a general WNW track during the next few days. Some development of this low/tropical wave is possible during the next several days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N78W to 11N91W to low pres 1009 mb near 10N104W to low pres 1009 mb near 16N113W to 12N129W to beyond 12N140W. Numerous moderate and scattered strong convection is observed from 05N to 09N between 78W and 80W. Scattered moderate convection is seen within 60 nm either side of a line from 14.5N112W to 12N123W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A gentle to moderate breeze will prevail in the vicinity of the northern and central Baja California Peninsula through mid week, increasing to moderate to fresh by the end of the week as the pressure gradient tightens slightly. Long period southerly swell propagating toward the coast of southern Mexico has peaked, and will decay for the remainder of the week. Fresh to strong northerly winds may pulse over the Gulf of Tehuantepec during the late night and early morning hours Thursday night through Saturday night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Nocturnal offshore winds will pulse to fresh in the Gulf of Papagayo through the week. Otherwise, moderate S to SW winds are expected S of the monsoon trough, with mainly light to gentle variable winds prevailing N of the trough through the week and into the upcoming weekend. Long period southerly swell and 6 to 9 ft seas will continue across the region tonight, but seas will subside to less than 8 ft by Tuesday evening. REMAINDER OF THE AREA... The remnant low of Jova is centered near 20N126W at 1008 mb moving WSW at 10 to 15 kt. The remnant low remains void of any deep convection. Scatterometer data from 1830 UTC showed a small area of fresh to strong winds on the NW side of the low facing the ridge of high pressure. Latest altimetry indicated corresponding seas of 8 to 9 ft in mixed swell. The low is forecast to continue to weaken and gradually dissipate by Thursday evening. Otherwise, the subtropical ridge continues to reside over the waters N of the monsoon trough, and will weaken in conjunction with the passage of the remnant low of Jova. The weakened ridge will generate moderate trade winds N of the monsoon trough through mid week. Persistent moderate to fresh SW winds S of the monsoon trough along with smaller areas of fresh to strong winds associated with convection have helped to create areas of 8 ft seas immediately to the S of the monsoon trough between 110W and 140W. The winds will diminish and seas will subside by Wednesday evening. Otherwise, an area of low pressure embedded in the monsoon trough near 104W will slowly move WNW along the monsoon trough. Expect rounds of scattered showers and thunderstorms along the monsoon trough through mid week. Seas will be 5 to 6 ft N of the monsoon trough, and 6 to 9 ft S of the monsoon trough through mid week. Seas S of the monsoon trough will then subside around a foot by Saturday. $$ CAM