178 AXPZ20 KNHC 020925 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 836 UTC Sun Sep 2 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... Hurricane Norman is centered near 17.1N 127.5W AT 02/0900 UTC moving WNW or 290 degrees at 13 kt. Estimated minimum central pressure is 970 mb. Maximum sustained wind speed is 90 kt with gusts to 110 kt. Additional strengthening is forecast during the next few days, and Olivia could become a hurricane by Tuesday. Numerous moderate to strong convection is seen within 75 nm of center. Numerous moderate convection is noted elsewhere from 14N to 18N between 125W and 129W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. Tropical Depression Seventeen-E is upgraded to Tropical Storm Olivia at 02/0900 UTC. At this time, Olivia is located near 16.0N 112.2W moving WNW or 300 degrees at 8 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is now 40 kt with gusts to 50 kt. Numerous moderate to strong convection is found within 30 nm NE and 180nm SW semicircles of center. No significant change in intensity is expected for the next day or so, however, short term fluctuations, up or down, could occur. Gradual weakening is expected to begin by Tuesday. Numerous moderate convection is elsewhere from 12.5N to 16N between 111W and 115W, with a cluster of moderate to strong convection from 15N to 16.5N between 114W AND 115W. See latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N84W to 10N90W to 11N100W to 13N105W. No significant convection. A cluster of moderate to isolated strong convection is N of 06N E of 79W. this convective activity is affecting the eastern part of the Gulf of Panama. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface trough is forecast to remain over the the Gulf of California and the Baja California Peninsula through at least Tue as T.S. Olivia passes S of a weakness in the subtropical ridge. Based on this weather pattern, the tropical cyclone would pass close to the offshore forecast waters through Tue evening. Recent scatterometer data indicate that the strongest winds associated with Olivia are currently in the southern semicircle of the cyclone's center. Swell generated by this system will propagate across the offshore forecast waters through Wed night. 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 Monday night. REMAINDER OF THE AREA... See the Special Features section for details on Hurricane Norman and Tropical Storm Olivia. Tropical Storm Miriam is centered W of area but it is still producing winds in the 20 to 25 kt range and seas of 9 to 12 ft for the forecast waters N of 23N W of 138W. Otherwise, a ridge dominates the forecast waters N of 20N W of 120W. The pressure gradient between the ridge and hurricane Norman supports moderate to fresh N to NE winds across the waters N of 20N W of 120W with seas of 8 to 11 ft due to mixed swell generated by the above mentioned tropical cyclones. Winds are also on increase S of hurricane Norman in a S to SW flow, particularly between 120W and 130W. An ASCAT pass confirmed the presence of these winds. Swell generated by tropical cyclones Miriam, Norman and Olivia will produce a large area of seas of 8 ft or greater for most of the waters N of 10N and W of 110W through Mon. $$ GR