000 AXPZ20 KNHC 132100 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2001 UTC Wed Sep 13 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Recently upgraded Tropical Storm Max near 16.1N 101.4W 1005 mb at 2100 UTC SEP 13 moving ENE or 70 DEG at 3 KT. Maximum sustained winds are 35 kt with gusts to 45 kt. Numerous moderate to strong convection is noted within 60 nm east semicircle of Max. Scattered moderate isolated strong convection is noted elsewhere from 13N to 17N between 98W and 103W. Max is forecast to move inland over southwest Mexico Thu night. Locally heavy rains are expected to spread inland with the system. These rains may cause life- threatening flash floods and mudslides. For additional information refer to NHC forecast advisories under WMO/AWIPS headers WTPZ21 KNHC/MIATCMEP1. Tropical Depression Fifteen-E is centered at 15.1N 121.3W 1005 mb at 2100 UTC SEP 13 moving W or 275 DEG at 6 KT. Maximum sustained winds are 30 kt with gusts to 40 kt. Scattered moderate to strong convection is noted within 210 nm west and 60 nm northeast quadrants. Scattered moderate isolated strong convection is noted elsewhere from 11N to 18N between 119W and 125W. This system will continuing moving generally westward and reach tropical storm intensity Thursday. For additional information refer to NHC forecast advisories under WMO/AWIPS headers WTPZ25 KNHC/MIATCMEP5. A 1009 mb surface low is analyzed along the monsoon trough near 15N111W, and is accompanied by scattered moderate isolated strong convection within 90 nm south of the low center. Scattered moderate convection is noted within 60 nm north semicircle of the low center. Environmental conditions are favorable for this system to strengthen to a tropical cyclone as it moves northward this week across the offshore waters between 105W and 112W. At the least, expect strong to near gale force cyclonic winds, and seas conservatively to 15 ft, and a large area of thunderstorms to reach near the entrance to the Gulf of California on Sat. INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N85W to 13N91W to Tropical Storm Max near 16.1N 101.4W to low pres near 15N111W to Tropical Depression Fifteen-E near 15.1N 121.3W to 10N126W to low pres near 10.5N135W to beyond 10N140W. Scattered moderate isolated strong convection was noted from 05N to 09N between 78W and 86W. Scattered moderate isolated strong convection was noted within 150 nm south of the monsoon trough between 104W and 115W. Scattered moderate isolated strong convection was noted within 60 nm of the monsoon trough between 128W and 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see special features section above for more on Tropical Storm Max, and low pres centered near 15N111W. A NW to SE oriented trough will meander E to W across the Baja California Peninsula and the Gulf of California with a surface low developing intermittently along the trough axis over the far northern Gulf waters. A W to E orientated ridge will meander from 23N116W to 21N110W through Thu night, then retract W on Fri as the previously described surface low, or tropical cyclone approaches the southern tip of the Baja Peninsula this weekend. Gulf of California...Light, mostly NW winds expected through Fri with large southerly swells arriving across the southern waters on Fri night ahead an approaching tropical low. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate southwesterly monsoonal flow is expected through the upcoming weekend with 6 to 8 ft seas primarily due to cross- equatorial swell that is forecast to subside below 8 ft on Fri night. REMAINDER OF THE AREA... High pressure of 1023 MB centered north of the area near 37N138W extends a ridge southeast to near 25N115W. Outside the influence of the tropical cyclones, light to locally moderate anticyclonic flow is expected to prevail N of the monsoon trough and W of 115W through the upcoming weekend. $$ AL