386 AXPZ20 KNHC 260906 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 525 UTC Sun Aug 26 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Recently upgraded Tropical Depression Fifteen-E near 13.3N 124.1W 1008 mb at 2 AM PDT moving W at 12 kt. Maximum sustained winds 30 kt gusts 40 kt. Fifteen-E will strengthen to a tropical storm near 13.5N 126.0W this afternoon, move to 13.7N 128.4W Mon morning, 13.9N 130.6W Mon afternoon, strengthen to a hurricane near 14.1N 132.6W Tue morning, and 14.3N 136.6W Wed morning. Fifteen-E will change little in intensity as it moves to 14.9N 140.1W early Thu, and continue to 17.4N 141.9W Fri. Scattered moderate to strong convection was noted with 30 nm of the center. Scattered moderate isolated strong convection is noted elsewhere from 10N to 15N between 121W and 127W. The system will continue on a WNW track while intensifying, forecast to reach tropical storm intensity this afternoon near 13.5N 126.0W, and hurricane intensity Monday night near 14.1N 132.6W. See the latest forecast/advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 KNHC for more details. A tropical wave axis is near 103W from 02N to 18N, moving W at 15 kt. Broad low pressure is developing in association with this tropical wave. Scattered moderate isolated strong convection is noted from 07N to 12N between 101W and 108W. There is a high probability that this area of low pressure will develop into a tropical cyclone within the next 5 days. Please refer to the latest eastern north Pacific Tropical Weather Outlook for more information. ...TROPICAL WAVES... A tropical wave axis is near 91W N of 03N, moving W at 15 kt. Associated convection is described in the Monsoon Trough section below. A tropical wave axis is near 103W from 02N to 18N, moving W at 15 kt. Please see above in special features section for more on developing low pressure and the possibility of tropical cyclone development in association to this feature. A tropical wave axis is near 132W from 03N to 18N, moving W at 10 to 15 kt. Associated convection is described in the Monsoon Trough section below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 10N104W to low pressure near 13N123.5W to 14N132W to 12N140W. Scattered moderate isolated strong convection is from 04N to 08N E of 80W, from 09N to 14N between 87W and 94W, from 11N to 17N between 95W and 100W, from 07N to 10N between 108W and 116W, and from 12N to 15N between 127W and 132W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure of 1037 mb centered near 44N143W extends a ridge SE to near the Revillagigedo Islands. The associated pressure gradient between the high and a persistent trough across the Baja California Peninsula will support moderate NW winds funneling along the coast of Baja through the next several days, with seas generally 4 to 5 ft. The highest seas are expected off of Baja California Norte and may briefly increase to 6 ft. Low pressure will deepen over the SW United States, with a trough extending across the Gulf of California early next week. This will help to freshen winds offshore of Baja California Norte Mon night through Wed. Seas over this area will then gradually build to 6 to 8 ft. Meanwhile, gentle to moderate southerly flow will persist over the Gulf of California this weekend, occasionally pulsing to fresh across north portions. Winds are expected to diminish early next week across south portion of the Gulf leading to variable winds. In the Gulf of Tehuantepec, nocturnal winds will be enhanced tonight with the passage of a tropical wave, with axis currently near 91W. Winds are expected to pulse to fresh to strong tonight. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will linger along 09N/10N during the next few days. Winds on both sides of the trough axis will generally be light to moderate. The main exception to this will be over the Gulf of Papagayo. Nocturnal offshore gap winds in the gulf will pulse to fresh to strong during the next several nights. REMAINDER OF THE AREA... Please see special features section above for more on recently upgraded TD 15-E, and for possible tropical cyclone development of broad low pressure associated with a tropical wave near 103W. Elsewhere, the pressure gradient between ridging across the northern waters and the monsoon trough will support moderate to locally fresh trades and 4 to 7 ft seas in mixed swell north of the monsoon trough and west of 120W through the remainder of the weekend. Wave heights will be relatively low for most of the forecast area this week. Long period swell is expected to arrive from the Southern Hemisphere this morning. Associated seas near the Equator will build, and peak at 6-8 ft, today through Mon. $$ AL