The National Weather Service placed central and southern Utah under a Flood Watch starting Monday, Sept. 28. Tropical moisture from Hurricanes Polo and Odalys is expected to push into the state through Tuesday, Sept. 29.

Alpine, Highland, Cedar Hills and Lehi all fall within a 15% flash flood risk zone that stretches along and south of Interstate 80, according to ABC4 Utah meteorologist Noah Price. Southern Utah faces a steeper threat: the Weather Prediction Center (WPC) issued a Day 3 Moderate risk there, meaning a 40% chance of flash flooding within 25 miles of any point in that zone.

Price called the Moderate designation unprecedented for the region.

"The flood threat confidence does continue to increase with the Weather Prediction center issuing a Day 3 Moderate risk of excessive rainfall across southern Utah for the first time ever," Price wrote Sunday, Sept. 27.

The NWS Salt Lake City office said the main areas of concern are recent burn scars, normally dry washes and slot canyons. The agency did not name specific locations within Utah County.

What's driving the rain

Hurricane Polo, weakening after a record stretch at Category 5 strength, is pulling moisture northward from the eastern Pacific. Hurricane Odalys, tracking northeast near Polo, is contributing additional moisture. An upper-level low over the Great Basin will steer that moisture into Utah, where a cold front could produce heavier thunderstorms, Price reported.

Separately, Fox Weather hurricane specialist Bryan Norcross reported Sunday that NOAA's Weather Prediction Center is showing a 3-out-of-4-level risk of flash flooding around the Four Corners region of Arizona, New Mexico, Colorado and Utah.

Local forecast

The NWS forecast for Lehi calls for showers likely on Monday with a high of 72°F, dropping to a low of 50°F Monday night with a chance of continued showers. Tuesday's forecast shows mostly sunny skies and a high of 73°F. Drier conditions are expected to return by Wednesday and Thursday as high pressure moves in.

The NWS also noted that severe to extreme drought conditions persist across much of Utah as of August 2026, though the agency did not connect the drought to this storm's flood risk.

What residents should know

As of Sunday, Sept. 27, the Lone Peak Fire District, Lone Peak Police Department, Lehi Police Department and local emergency management had not posted public statements about this storm. Residents can monitor current watches and warnings at the NWS Salt Lake City website.