Thunderstorms to Increase Flood Risk Across Southwest US Into Midweek

An upper-level area of low pressure will slowly track eastward across the Southwest and produce rounds of showers and thunderstorms into Wednesday.

Tropical moisture will surge northward from the eastern Pacific and aid in the development of widespread showers and thunderstorms.

Southwest Short-Range Regional Weather Forecast

This upper-level low was responsible for some showers across Southern California on Sunday, including Los Angeles and Death Valley.

Any thunderstorms that do develop could produce locally heavy rainfall and bring the risk for flash flooding.

According to AccuWeather Meteorologist Evan Duffey, "Whenever heavy shower and thunderstorm activity spreads across the southwestern United States, it presents certain dangers to area residents."

"Seeing as the region is very dry for most of the year, and given the soil structure of the Desert Southwest, rainfall is not absorbed fast enough and water running on the surface often finds its way to dry creek and drainages," he added.

The heaviest rain will be confined across portions of southern Nevada, northern and eastern Arizona, southeastern Utah, southwestern Colorado and western New Mexico.

Locations within the flood threat include Las Vegas; Flagstaff, Arizona; Bluff, Utah; Grand Junction and Durango, Colorado; and Gallup, New Mexico.

Those heading home from work during the afternoon commutes may have to deal with slippery roadways and blinding downpours. Drivers are urged to slow down to prevent the risk of hydroplaning.

While the greatest chance for the heaviest rain will fall across the mountains, this water will quickly flow down the mountains and create flash flooding and mudslides in nearby valleys.

"These 'gully washers' can quickly catch people off guard, and can occur many miles away from where the rain actually occurred," Duffey said.

Travel could become dangerous at times along interstates 10, 15, 17, 25, 40 and 70.

Never drive through a flooded roadway. Only a few inches of rushing water can wash away vehicles.

Conditions will improve across much of the Southwest on Wednesday as thunderstorms will be confined across Colorado, New Mexico and western Texas.

Use ​AccuWeather Minutecast® to get a minute-by-minute precipitation forecast for your area.