Monsoonal Moisture Fueling Southwest Flood Threat

The moisture began to return to the Southwest during the last week of July.

On July 30th, thunderstorms across the Southwest produced dust storms, wind damage and locally heavy rain, especially in Arizona. 

• Dust storms, with visibilities near zero occurred in the Arizona counties of La Paz, Pinal, Yuma, Yavapai and in Riverside County, California.
• A wind gust of 89 mph was reported at Gila Bend, Arizona.
• Wind gusts to 70 mph in Phoenix, Arizona, knocked down power lines and over 25, 000 customers were without power for a time, according to Arizona Public Service.
• There was a report of 1.02 inches of rain just north of Scottsdale, Arizona.

Thunderstorms developed Sunday evening, July 31st, in Arizona, Utah and Nevada, and some flash flooding was reported in southeast Arizona and southeast Nevada, due to storms sitting over the same areas for multiple hours at a time.

Showers and storms developed again Monday, August 2nd, across the same areas, with flash flooding reported in southern Utah due to slow-moving downpours.

Heavy downpours led to flash flooding in the Phoenix area on Tuesday, August 2nd. Several roadways in the area were closed due to the flooding, including Interstate 17, which caused a major traffic nightmare during the evening commute.

Heavy rain caused street flooding in Flagstaff, Arizona, on Wednesday, August 3rd. Additionally, some homes and businesses in the area had water up to their doorsteps.

On Friday morning, August 5th, Scottsdale, Arizona picked up 0.88" in just 30 minutes, which resulted in curb-to-curb flooding. More than two inches of rain fell in Scottsdale in a 24-hour window. Water rescues occurred in northern Phoenix after water climbed more than a foot.  

MORE ON WEATHER.COM: Arizona Dust Storm