Wind gusts up to 70 mph, hail and flash flooding threaten Bountiful, Farmington, Woods Cross and North Salt Lake. The National Weather Service's Storm Prediction Center issued Severe Thunderstorm Watch 619 for Davis County and 10 other northern Utah counties at 3:30 p.m. Sunday, Aug. 23, with the watch running until 10 p.m. MDT.

The Storm Prediction Center placed the Wasatch Front under a "Slight" risk for severe thunderstorms, a level 2 on a 5-point scale. The broader Northern and Central Utah region sits at "Marginal," or level 1. Monsoonal moisture combined with afternoon highs in the low to mid-90s is fueling the threat.

ABC4 meteorologist Seth Sanders wrote in his Sunday forecast that "the main concern will be powerful wind gusts up to 70 mph, but hail and flooding will also be a possibility."

KUTV meteorologist Jill Margetts put the probability of 70-mph-plus gusts at 10% for any given point along the Wasatch Front during Sunday afternoon and evening thunderstorms, according to KUTV's storm preview.

The Weather Prediction Center also issued a "Marginal" excessive-rainfall threat covering nearly all of Utah, indicating a 5% chance of flash flooding within any 25-mile area.

Saturday night offered a preview. The NWS issued a severe thunderstorm warning for parts of Weber, Cache and Box Elder counties with gusts reaching 70 mph, and storms downed power lines across Ogden.

What residents should do:

• Secure loose outdoor furniture, trampolines and trash cans before storms arrive.
• Stay indoors during active thunderstorms; avoid windows.
• Do not drive through flooded roadways. Turn around, don't drown.
• Monitor the NWS Salt Lake City flash flood page or call 801-524-5133 for updates.

The storm threat is expected to diminish after 10 p.m. Sunday. High pressure returns Monday, cutting off the monsoonal moisture pipeline, though isolated mountain thunderstorms remain possible through Tuesday.