Fast-moving afternoon thunderstorms turned into a flash flood emergency for Benson and the I-10 corridor on Thursday, as sudden runoff spilled into low washes and across roadways. Local officials warned that even shallow, fast-moving water could quickly make streets and underpasses impassable, urging people in the warned area to move to higher ground until conditions improved.
What Officials Warned
The National Weather Service office in Tucson put the Upper San Pedro River Valley, including Benson, under a Flash Flood Warning through 7:15 p.m. MST on Thursday, according to NWS Tucson. Forecasters said storms could send rapid runoff into channels and washes that drain toward town and urged residents to stay away from low-water crossings.
Map, Exposures And Travel Impacts
The Arizona Department of Transportation amplified the alert on X, sharing a map that highlighted Benson, St. David and Curtiss and flagged the I-10 corridor as at risk, according to Arizona DOT on X. The post estimated that roughly 6,345 people, eight schools and one hospital were inside the warned area and reminded drivers not to attempt to drive through flood waters.
Safety Advice And Monsoon Context
Officials repeated the familiar monsoon safety message: do not drive through moving water and move to higher ground immediately. That guidance mirrors the National Weather Service's flood-safety advice. The alert arrived as Arizona moves through the official monsoon window, June 15 through Sept. 30, a season when sudden thunderstorms can produce dangerous local runoff, according to Drought.gov.
Local Impact And Where To Check Updates
Cochise County's alert feed listed Benson and St. David among the communities affected and urged residents to follow official instructions posted on the county alert page, according to Cochise County Alerts. The county also pointed people toward local emergency contacts and available shelter information. Drivers planning to use I-10 were advised to check conditions and any closures on AZ 511 before heading out.
