000 AXPZ20 KNHC 191005 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Aug 19 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 0600 UTC surface analysis and satellite imagery through 0830 UTC. ...SPECIAL FEATURES... Tropical Depression Twelve-E has developed into a tropical storm. The center of Tropical Storm Kay at 19/0900 UTC is near 18.4N 110.9W, or about 275 nm to the south-southwest of the southern tip of Baja California. Kay is moving northwestward, or 315 degrees, 6 knots. The estimated minimum central pressure is 1005 mb. The maximum sustained wind speeds are 35 knots with gusts to 45 knots. Convective precipitation: Latest satellite imagery shows a large burst of numerous strong convection within 90 nm of the center in the south and southwest quadrants. Scattered moderate to isolated strong convection is within 120 nm of the center in the north semicircle. Please read the latest NHC Public Advisory under AWIPS/WMO headers MIATCPEP2/WTPZ32 KNHC and the Forecast/Advisory under the AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is along 99W from 17N southward, moving westward 10 to 15 knots. Convective precipitation: Scattered moderate isolated strong within 60 nm on either side of the tropical wave from 13N to 17N. A tropical wave is along 138W/139W from 18N southward, moving westward 5 to 10 knots. Convective precipitation: isolated moderate to locally strong from 11N to 13N between 139W and 140W, and from 16N to 19N between 138W and 140W. The surface pressure gradient that exists between the tropical wave and surface ridge that is to the north is still tight enough in order to support fresh trade winds on the northern side of the system. This is allowing for an area of combined seas that is near 8 feet to linger. These seas will subside as the wave reaches 140W by 24 hours. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W tO 08N90W tO 08N98W... and along 14N114W to 13N122W to 10N132W. Convective precipitation: scattered to numerous strong within 60 nm to the north and to the south of the monsoon trough between 116w and 130w. Scattered moderate to isolated strong from 03N to 06N to the east of 80W, to the north of 07N between 79W and 84W, and from 10N to 12N between 93W and 94W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface ridge is along 17N123W, to 23N130W, beyond 30N140W. The most recent scatterometer data were showing gentle to moderate northerly flow around the ridge from 20N northward, and combined seas of 4 to 7 feet. Light to moderate southerly wind flow prevails in the Gulf of California with a north to south trough located along the eastern shore of the Baja California peninsula. Little change in these conditions is anticipated during the next several days. It is possible that winds may pulse to moderate to fresh just offshore of the western coast of the Baja California peninsula late this weekend into early next week as the pressure gradient tightens slightly. The ridging is forecast to break down as a decaying cold front or remnant trough drops into the northern part this weekend, stalling and lingering over the northwest part through early next week. This will allow for trades to diminish to mainly light to moderate as the pressure gradient weakens. The main feature of interest is recently formed Tropical Storm Kay. Please refer to the special features section for details. Moderate breezes are in the Gulf of Tehuantepec. Moderate to fresh offshore wind flow is anticipated during the overnight hours through early next week. Convective precipitation along the Mexico coast: scattered strong from 20N to 22N to the east of 109W. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to locally fresh northeast to east offshore winds are expected again in and just downstream of the Gulf of Papagayo early this morning. Light to moderate winds will prevail on either side of the monsoon trough through early next week with combined seas of 4 to 7 feet. The remainder of the area...The aforementioned ridge is forecast to break down as a decaying cold front or remnant trough drops into the northern part this weekend, stalling and lingering over the northwest part through early next week. This will allow for trades to diminish to mainly light to moderate as the pressure gradient weakens. $$ MT