477 AXPZ20 KNHC 041501 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1351 UTC Tue Sep 4 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... At 04/1500 UTC, Hurricane Olivia is centered near 17.0N 118.2W moving W or 275 degrees at 10 kt. Estimated minimum central pressure is 971 mb. Maximum sustained wind speed is 90 kt with gusts to 110 kt. Numerous moderate to strong convection is found within 60 nm of center, except 120 nm SE quadrant. Scattered moderate isolated strong convection is noted elsewhere from 12N to 19N between 115W and 122W. Olivia is forecast to continue on a westward track the next 24 hours while intensifying to 100 kt, with gusts to 120 kt. The system will start to move on a WNW track with an increase in forward speed Wed, with a weakening trend commencing. See latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...TROPICAL WAVES... The axis of a tropical wave is near 95W N of 05N. Scattered moderate isolated strong convection is noted from 05N to 13N between 92W and 96W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 09N91W to 11N99W to 10N105W to 11N108W. Scattered moderate isolated strong convection was noted from 04N to 10N E of 91W, from 09N to 13N between 98W and 108W, and from 15N to 18N between 98W and 103W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface trough is forecast to meander between the the Gulf of California and the Baja California Peninsula today. By Wed, a ridge is forecast to build across the region as tropical cyclone Olivia moves westward and away from the offshore forecast waters. However, swell generated by Olivia is forecast to propagate across the offshore forecast waters through Wed. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will linger near 09/10N during the next few days. Winds on both sides of the trough axis will be gentle to moderate, and seas of 4 to 6 feet are expected through Wed. Long period SW swell will continue to propagate across the region during the next several days, building seas to 8 or 9 ft toward the end of the work week, particularly between Ecuador and the Galapagos Islands, then across the pacific waters of Costa Rica and Panama. REMAINDER OF THE AREA... Please see the Special Features section above for details on Hurricane Olivia. Hurricane Norman continues to move further from the forecast waters, and its influence on the area decreases. Winds and seas generated from Norman will fall below advisory criteria over the forecast waters Wed. Otherwise, a ridge dominates the forecast waters N of 20N W of 120W, with gentle to moderate winds prevailing. Seas generated by Olivia will continue to propagate mainly across the waters from 10N to 25N between 110W and 130W during the next couple of days. $$ AL