ZCZC MIATCDEP2 ALL TTAA00 KNHC DDHHMM Hurricane Genevieve Discussion Number 13 NWS National Hurricane Center Miami FL EP122020 900 AM MDT Wed Aug 19 2020 Genevieve continues to have a fairly well-defined eye in geostationary satellite imagery, however a recent SSMIS microwave overpass shows that the eyewall is open to the southwest and that deep convection is generally lacking over the southwestern portion of the circulation. The various satellite intensity estimates range from about 80-96 kt, which SATCON being at the higher end. The cloud tops over the northeastern portion of the circulation have cooled within the past few hours, so the initial intensity is held at a possibly generous 100 kt. An Air Force Reserve hurricane hunter aircraft is scheduled to investigate Genevieve this afternoon, and should provide a better assessment of the hurricane's intensity and size. The hurricane has continued to move slightly right of track, and the initial motion estimate is 335/8 kt. A north-northwestward motion is expected to continue today, followed by a turn toward the northwest tonight as mid-level ridging builds over northwestern Mexico. The new NHC forecast track has again been shifted slightly east of the previous track at 12 and 24 hours, but it is essentially unchanged thereafter. This track adjustment brings the center a little closer to the southern portion of the Baja California peninsula tonight and early Thursday. Only a slight deviation to the right of the track would bring hurricane-force winds onshore, and the government of Mexico has issued a Hurricane Warning for a portion of the southern coast of Baja California. Genevieve is forecast to move over gradually decreasing sea surface temperatures over the next couple of days, which should result in slow weakening during that time. After 48 hours, the cyclone will encounter much cooler waters and a more stable air mass. Therefore, a more rapid rate of weakening is expected after that time, with the system becoming a remnant low by 96 hours. The NHC intensity forecast is a blend of the statistical and dynamic model guidance. Key Messages: 1. The center of Genevieve is forecast to pass near or just west of the Baja California peninsula. Tropical storm conditions are expected to spread across southern Baja California Sur this afternoon and continuing through Thursday. Hurricane conditions are expected within the Hurricane Warning area beginning tonight and continuing into Thursday. 2. Heavy rainfall from Genevieve may lead to life-threatening flash flooding and mudslides across portions of far southern Baja California Sur through Thursday. 3. Large swells generated by Genevieve are affecting portions of the coast of southern Mexico and will spread northward along the coast of Mexico to the Baja California peninsula through Thursday. FORECAST POSITIONS AND MAX WINDS INIT 19/1500Z 20.9N 109.7W 100 KT 115 MPH 12H 20/0000Z 21.7N 110.2W 90 KT 105 MPH 24H 20/1200Z 22.6N 111.1W 85 KT 100 MPH 36H 21/0000Z 23.4N 112.3W 80 KT 90 MPH 48H 21/1200Z 24.3N 113.6W 75 KT 85 MPH 60H 22/0000Z 25.5N 115.4W 60 KT 70 MPH 72H 22/1200Z 26.6N 117.2W 50 KT 60 MPH 96H 23/1200Z 28.9N 120.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 24/1200Z 30.5N 122.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Brown NNNN