By Reginald Stanley. Posted August 20, 2023, 2:33 AM.

Shortly after midnight on August 20, the Storm Prediction Center issued a slight risk of severe thunderstorms, some of which may have tornado potential, across an interior portion of Southern California for Sunday afternoon.

According to the Storm Prediction Center, severe thunderstorms may develop on Hilary's east side beginning late Sunday morning and into the afternoon, as the tropical cyclone moves up into California. These thunderstorms are predicted to move into interior portions of Southern California early Sunday afternoon. Rotating supercell thunderstorms have potential to develop within Hilary's convective bands during this period, and one or multiple of these supercells may have the potential to produce tornadoes due to favorable conditions. Among these conditions aiding possible tornado development include a strong low-level jet over southeastern California, a veering of winds at low to mid-levels, low-level shear and strong uplift. The areas with the greatest threat of tornado potential includes the southwestern Mojave Desert and Imperial Valley, with areas of inland Southern California outside of the deserts, along with western Arizona, remaining at marginal risk (2 percent) for tornado development - this includes western Riverside County, southern San Bernardino County, non-coastal areas of San Diego County and all of Imperial County.

The tornado threat is being monitored very closely by meteorologists and updates have been frequent. Tornadoes have occurred in California before, and the state averages six per year - however, most tornadoes were relatively weak, short-lived, and typically rated low on the Fujita/Enhanced Fujita scale (typically EF-0 and EF-1, with a couple of EF-2 tornadoes) and the Storm Prediction Center notes that the meteorological conditions present in Hurricane Hilary suggests a more prolific tornado environment that the region has never seen before. Despite this, the risk remains low, but not impossible. If you see a tornado on the ground or a tornado warning is issued for your area, seek shelter immediately in the lowest, most central part of your home or building. If a basement or well-constructed underground shelter is accessible, take shelter there. Avoid windows, glass, and vehicles. A tornado may not be easily visible due to the presence of heavy precipitation. Additionally, non-tornadic thunderstorm-related wind damage also poses a threat.