000 AXPZ20 KNHC 212118 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2010 UTC Fri Aug 21 2020 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... Genevieve becomes a Post-Tropical Cyclone and the the last advisory was issued by the National Hurricane Center at 21/2100 UTC. At this time, Genevieve is centered near 25.8N 115.5W at 21/2100 UTC moving NW or 320 degrees at 10 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. A recent scatterometer pass shows the well defined cyclonic circulation associated with Genevieve, with tropical storm force winds within about 75 nm of the center in the NE quadrant. No deep convection is related to the system, forecast to dissipate within a few days. Large swells from Genevieve that are affecting portions of the west coast of the Baja California peninsula will gradually subside through Saturday. These swells are likely to cause life- threatening surf and rip current conditions. Please read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPEP2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP2.shtml for more details. ...TROPICAL WAVES... A tropical wave axis is analyzed near 88W N of 03N. This is the tropical wave which helped spawn T.D. 14 in the western Caribbean. The wave, combined with the monsoon trough, is helping to induce scattered moderate to isolated strong convection from 11N to 13N between 88W and 90W. This convective activity is affecting parts of Central America. Heavy rainfall could lead to flash flooding over portions of Central America through the weekend. A tropical wave axis is analyzed near 112W from 04N to 18N, moving W at 10-15 kt. Scattered moderate convection is noted from 12N to 15N between 110W and 120W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 12N87W to 1011 mb low pressure near 11N100W to 16N108W to 15N124W to 11N140W. Besides the convection described above, scattered moderate and isolated strong convection is noted from 10N to 15N between 100W and 106W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details about Genevieve. Elsewhere, expect fresh to strong S to SE winds in the northern Gulf of California through this evening, with seas around 5-7 ft. An scatterometer pass confirmed the presence of these winds N of 29N. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to fresh SW winds prevail south of the monsoon trough. Associated seas are 7-9 ft. Expect freshening winds and building seas off the coast of Central America through the upcoming weekend and into early next week. Seas will build to 8-10 ft offshore of Central America by this weekend in association with the strongest winds, then continue building to 9-11 ft early next week as monsoonal flow continues strengthening. REMAINDER OF THE AREA... A ridge dominates the northern forecast waters N of 20N and W of 125W. A low pressure area moving northward just W of the area will bring some increase in winds and seas across the west- central waters over the next 24-48 hours, particularly from 10N-15N W of 135W. Expect fresh to locally strong S-SW winds and seas in the 8-10 ft range. Recent scatterometer data indicate moderate to fresh S to SW winds S of the monsoon trough across most of the forecast region. These winds slightly increase near a pair of low pressure areas located along the monsoon trough. This monsoonal flow is expected to strengthen E of 115W this weekend into early next week, with seas building to 8-12 ft. One of the low pressure area is located several hundred miles south-southwest of the southern tip of the Baja California peninsula, and is producing a large area of disorganized cloudiness and thunderstorms. Conditions appear favorable for some gradual development of this system, and a tropical depression is likely to form during the early to middle part of next week while it moves little. Another area of low pressure is likely to form south of the Gulf of Tehuantepec early next week. Some slow development of this system is possible thereafter while it drifts northwestward or northward. $$ GR