263 AXPZ20 KNHC 040757 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 710 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Tropical Storm Olivia is centered near 16.8N 116.0W moving W or 275 degrees at 8 kt. Estimated minimum central pressure is 987 mb. Maximum sustained wind speed is 65 kt with gusts to 80 kt. Numerous moderate to strong convection is found within 60 nm of center, except 90 nm SE quadrant. Numerous moderate convection is noted elsewhere from 14N to 18N between 114W and 118W. See latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is along 94W N of 05N. Scattered moderate convection is near the southern end of the wave axis. Scattered moderate isolated strong convection is from 10N to 11N between 93W and 95W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N84W to 09N90W to 11N100W to 10N105W to 11N109W. Clusters of moderate to isolated strong convection are near 05.5N84W and near 05N89W. Similar convection is also noted within 90 nm N of trough between 104W and 106W. Scattered moderate convection is from 05N to 07N betwen 92W and 97W, and from 07N to 10N between 107W and 112W. ...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 through Tue. 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 are 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 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... The last advisory was issued by the National Hurricane Center on Hurricane Norman at 04/0300 UTC. This tropical cyclone has moved into the Central Pacific region, but it is still producing fresh to strong winds across the western forecast waters, mainly from 20N to 28N W of 135W due to the pressure gradient between the tropical cyclone and a ridge to the N. Seas within this area of winds are in the 10 to 20 ft range in mixed swell, with the highest seas along 140W. Olivia has been upgraded to hurricane status, and it is the ninth hurricane that has formed in the Eastern Pacific region this busy hurricane season. Please, see the Special Features section for details on Hurricane Olivia. Otherwise, a ridge dominates the forecast waters N of 20N W of 120W. Seas will begin to subside across the waters N of 08N W of 130W as tropical cyclone Norman moves westward and away from the forecast area. 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. $$ GR