481 AXPZ20 KNHC 040230 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 158 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Hurricane Norman is centered near 19.8N 140.2W AT 04/0300 UTC moving W or 280 degrees at 18 kt. Estimated minimum central pressure is 975 mb. Maximum sustained wind speed is 80 kt with gusts to 110 kt. Steady weakening is expected during the next several days. Numerous moderate and scattered strong convection is seen within 60 nm of the center. Scattered moderate convection is noted elsewhere from 18N to 21N between 138W and 141W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. Tropical Storm Olivia is upgraded to hurricane status at 04/0300 UTC. At this time, 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 65 kt with gusts to 80 kt. Numerous moderate to strong convection is found within 90 nm of center, except 90 nm SW qudrant. Scattered moderate to strong convection is noted elsewhere from 14N to 18N between 113W and 118W. See latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...TROPICAL WAVES... The axis of tropical wave is near 91W N of 05N. Scattered moderate convection is near the southern end of the wave axis. Similar convective activity is noted along the wave's axis over parts of Guatemala, western Honduras and El Salvador. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 09N90W to 11N100W to 10N105W to 12N110W. Scattered moderate convection is noted from 05N to 07N between 87W and 94W, and from 07N to 12N between 106W and 113W. ...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 early 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... See the Special Features section for details on Hurricane Norman and Hurricane Olivia. Otherwise, a ridge dominates the forecast waters N of 24N. The pressure gradient between the ridge and hurricane Norman is supporting moderate to fresh N to NE winds across the area N of 24N W of 125W, with seas of 8 to 11 ft due to wind waves and mixed swell generated by Norman. Swell generated by tropical cyclones Norman and Olivia will produce a large area of seas of 8 ft or greater for much of the waters N of 10N and W of 110W through tonight. $$ GR