The North American monsoon is arriving in the Desert Southwest, and what is a monsoon matters now because this seasonal wind shift is expected to fuel the first widespread summer thunderstorms this weekend into next week. The setup brings needed moisture, but it also raises the risk of gusty winds, blowing dust, and flash flooding across several states.
Flagstaff and Yavapai
The National Weather Service in Flagstaff said strong to locally severe thunderstorms were moving through Yavapai and Gila counties through the afternoon and evening. Outflow gusts of 30 to 50 mph, with isolated gusts to 60 mph, were expected along Interstate 17 and the Mogollon Rim.
Localized flash flooding was possible from the Rim and White Mountains southward. That leaves drivers, hikers, and anyone in low-lying drainages with a fast-moving threat, especially where runoff can jump roads with little warning.
Arizona Dust Corridor
Sunday into Monday was the first significant monsoon burst of the season. Active monsoon conditions were expected to lock in Monday as deeper moisture flooded the region.
Interstate 10 between Phoenix and Tucson remained a marquee dust corridor, and Maricopa County still flagged blowing dust as the leading daytime hazard even as afternoon storm chances climbed. Phoenix was still running 108 to 110°F, so the same pattern that can deliver rain also leaves room for walls of dust and dry lightning.
Four Corners and Ruidoso
The Weather Prediction Center expanded a Marginal Risk of excessive rainfall into Tuesday and Wednesday, broadening the flash flooding threat north into the Great Basin and northern Rockies. Daily storms and a flash flood risk were expected through Wednesday, most concentrated near the Four Corners but possible border to border, with the heaviest rain over southeast Utah and southwest Colorado.
Storms over the Seven Cabins and other area burn scars near Ruidoso could push debris-laden water across the road with almost no warning. Haboobs, which are large dust walls, were also possible as gusty outflow winds and blowing dust built around the storms. For readers across Arizona, New Mexico, southern Utah, southern Colorado, and Nevada, the next several days favor scattered to numerous afternoon and evening thunderstorms rather than a single isolated round.
