Monsoon storms raise flash flood risk across Utah

Monsoon moisture brings an increased risk of thunderstorms, heavy rain and flash flooding across parts of Utah. Photo: Alexey Sabulevskiy

Southern Utah faces the greatest threat, while afternoon thunderstorms could develop across the state

PARK CITY, Utah — Monsoon moisture will continue to fuel thunderstorms across Utah, bringing heavy rain, lightning, gusty winds and an elevated risk of flash flooding.

ABC4 Utah reported that scattered thunderstorms are expected to develop during the afternoon and evening hours, with the greatest flash flood danger concentrated across southern Utah. Storms could produce intense rainfall over a short period, particularly in slot canyons, normally dry washes, low-lying areas, and recent wildfire burn scars.

The National Weather Service Weather Prediction Center defines its excessive rainfall outlook as the probability that rainfall will exceed local flash flood guidance within 25 miles of a location. A marginal risk means there is at least a 5% chance, while a slight risk represents at least a 15% chance.

Although southern Utah is expected to face the highest risk, thunderstorms may also develop over Utah’s northern mountains, including the Wasatch Range. Storms in higher terrain can form quickly and bring dangerous lightning, brief heavy rainfall, and strong, erratic winds.

The National Weather Service advises hikers and other outdoor recreationists to check the latest forecast before entering canyons or exposed mountain terrain. Flash flooding can occur even when rain falls several miles upstream, sending water and debris through areas where skies may still appear clear.

Drivers should never attempt to cross a flooded roadway. Water depth and road damage can be difficult to judge, and rapidly moving water can sweep away a vehicle.

Monsoonal moisture is expected to keep daily thunderstorm chances in the forecast, according to ABC4 Utah. Conditions can change quickly, and residents and visitors should monitor weather alerts throughout the day.