307 WTPZ42 KNHC 091453 TCDEP2 Tropical Storm Kay Discussion Number 21 NWS National Hurricane Center Miami FL EP122022 800 AM PDT Fri Sep 09 2022 Kay is gradually becoming less organized. There is currently minimal convection near its center of circulation, although there is a complex of convective bands occurring about 75-150 n mi north of the center. Doppler radar data from Yuma and San Diego has shown winds as high as 60 kt aloft, although it is unclear how well these winds are mixing down to the surface. Based on the radar and satellite intensity estimates, the initial intensity is reduced to 45 kt, and this could be a bit generous. An Air Force Reserve Hurricane Hunter aircraft is enroute to investigate Kay. Kay should continue to weaken as it reaches sea surface temperatures of 20-21C by 24 h, and the dynamical model suggest it should stop producing convection near or just after that time. The new intensity forecast shows the cyclone as a minimal tropical storm in 24 h, followed by decay to a remnant low as the convection dissipates and the winds drop below tropical-storm force. The global models indicate that the remnant low should dissipate between 96-120 h, and the new intensity forecast follows this. The initial motion is now northwestward or 320/ 11 kt. A mid-level ridge to the north of Kay is expected to cause the cyclone to gradually turn west-northwestward away from land in the next 12 h, followed by a westward turn between 12-24 h. After that time, low-level ridging in the Eastern Pacific should steer the remnant low slowly southward and then southeastward before the system dissipates completely. There was little change in the track forecast guidance since the last advisory, and the new forecast track is similar to the previous track. Although Kay's intensity has decreased, the tropical cyclone 34-kt wind radii remain quite large on its eastern side. Wind, surf, and rainfall impacts continue to extend far from the center so users should not focus on the exact forecast track of Kay. KEY MESSAGES: 1. As the center of Kay passes just offshore, heavy rainfall will likely result in flash flooding, including possible landslides, across the Baja California peninsula and portions of mainland northwestern Mexico through Saturday morning. Flash, urban, and small stream flooding is likely across Southern California beginning today, especially in and near the peninsular ranges. Flash, urban, and small stream flooding is possible beginning today in Arizona and southern Nevada. 2. Tropical storm conditions are occurring over portions of the Baja California peninsula, and these conditions extend all the way to the northern Gulf of California coastline, where a Tropical Storm Warning is in effect. 3. Strong winds not directly associated with Kay's core wind field are occurring across portions of southern California and extreme southwestern Arizona. For information on this wind hazard, users should see High Wind Warnings and other products from their local NWS Weather Forecast Office. FORECAST POSITIONS AND MAX WINDS INIT 09/1500Z 30.3N 116.7W 45 KT 50 MPH 12H 10/0000Z 31.1N 118.1W 40 KT 45 MPH 24H 10/1200Z 31.4N 119.5W 35 KT 40 MPH 36H 11/0000Z 31.4N 120.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 11/1200Z 31.0N 121.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 12/0000Z 30.3N 121.7W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 12/1200Z 29.6N 121.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 13/1200Z 28.5N 120.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 14/1200Z...DISSIPATED $$ Forecaster Beven