An Analysis of Unique Atmospheric Observations during Multiple California PSPS Events

Millions of Californians experienced a series of public safety power shutoffs (PSPS) in 2019. The Kincade Fire ignited 23 October 2019 during a PSPS and persisted during a subsequent PSPS. The fire ignition occurred concurrent with very windy conditions and it rapidly spread to thousands of acres. Four days later, on 27 October, a subsequent wind event with even greater intensity prompted the successive PSPS. Surface wind gusts were recorded in excess of 44.7 m s^-1 (100 mph) during the second PSPS. A unique observational dataset was collected for both events including, lidar derived vertical wind profiles, lidar retrieved backscatter, mobile Ka-band radar reflectivity and radial velocities, and in situ surface weather conditions. A case study for these events was performed using these unique data and high-resolution WRF numerical weather simulations to better understand the meteorological conditions that provoked these controversial PSPS events. Preliminary results have exposed the possibility of three downslope wind events impacting this area within a matter of eight days.