903 AXPZ20 KNHC 020329 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 158 UTC Tue Oct 2 2018 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 0300 UTC. ...SPECIAL FEATURES... The center of Rosa is passing N of Isla Cedros while approaching the coast of northern Baja California. Tropical Storm Rosa is centered near 28.9N 115.3W at 02/0300 UTC or 65 nm N of Punta Eugenia, Mexico moving toward the NE at 9 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Rosa is completely exposed with no significant shower or thunderstorms in its vicinity. Most of the convective activity associated with this tropical cyclone is now over the northern Gulf of California and the far NW Mexico. On the forecast track, the center of Rosa will be near the coast of the Baja California peninsula during the next few hours and then move across the peninsula into the northern Gulf of California. Rosa's remnants are then expected to move across the Desert Southwest on Tuesday. Swells generated by Rosa will affect portions of the coasts of southwestern Mexico, most of the west coast of the Baja California peninsula, and southern California through Tuesday. These swells are likely to cause life-threatening surf and rip current conditions. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 KNHC for more details. Farther south, Tropical Storm Sergio is upgraded to hurricane status at 02/0300 UTC. At this time, Sergio is centered near 10.9N 112.0W or 660 nm SW of Manzanillo, Mexico moving W at 12 kt. and this general motion is forecast to continue through tonight. A turn toward the west-northwest is expected on Tuesday and a northwestward motion is forecast on Wednesday. Estimated minimum central pressure is 992 mb. Maximum sustained wind speed has increased to 65 kt with gusts to 80 kt. Numerous moderate to strong convection is noted within 120 nm of SE and 75 nm NW semicircles of center. In addition, scattered moderate to isolated strong convection is noted from 07N to 12N between 109W and 114W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP1/WTPZ31 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N83W to 10N95W to 11N105W. Another segment of the monsoon trough reaches from 15N120W to beyond 10N140W. Scattered moderate isolated strong convection is within 150 nm S of the trough between 85W and 89W. Scattered moderate convection is from 07N to 11N between 93W and 101W. Similar convection is also noted from 12N to 15N between 124W and 130W, and from 10N to 12N W of 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See Special Features above for information on T.S. Rosa and Hurricane Sergio. Swell associated with Rosa is still affecting the offshore forecast waters mainly N of 23N E of 120W. Farther south, swell generated by Sergio, with seas to around 8 ft, is reaching the coast of Colima and Guerrero based on a recent altimeter pass. This swell event is also reaching the Revillagigedo Islands, and could produce dangerous surf conditions in the coastal areas. In the Gulf of California, the most recent scatterometer pass confirmed the presence of fresh to strong NE-E winds across the far northern Gulf, ahead of Rosa, and moderate to fresh southerly winds across the central Gulf. Tropical storm conditions from Rosa are possible across the northern Gulf of California tonight. Winds and seas will diminish rapidly thereafter over the northern Gulf of California through late Tue. Scattered moderate to isolated strong convection is also noted over the northern Gulf of California ahead of Rosa. In the Gulf of Tehuantepec, pulsing winds of 20 to 30 kt are expected during the overnight and early morning hours through at least early Wed morning. Seas are forecast to build to 9 or 10 ft with the strongest winds. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will meander between 09N and 12N through Fri, with gentle to moderate winds expected on either side of the trough axis through Wed. Moderate to fresh southwesterly flow and building seas to 8 ft are expected S of the monsoon trough and mainly E of 95W by Thu. These marine conditions may persist through Sat. REMAINDER OF THE AREA... See Special Features above for information on Tropical Storm Rosa and Hurricane Sergio. A cold front continues to move SE across the NW waters, and extends from 30N128W to 23N140W. The front will sweep eastward across the waters north of 20N through mid week, but become diffuse before reaching 120W. This weather pattern will keep the trade wind flow minimal farther south into the deep tropics. NW swell in the wake of the front will propagate across the NW waters through Tue, while seas associated with Rosa will subside to less than 8 ft W of the Baja California Peninsula. Later in the week, seas associated with Sergio will mix with additional pulses of long period NW swell. By Thu, seas of 8 ft or greater are expected to cover most of the waters N of 10N W of 105W, including the entrance of the Gulf of California. $$ GR