Tucson, Arizona – Residents across southeast Arizona should prepare for an increasingly active monsoon pattern this week as thunderstorms become more widespread and the threat of flash flooding grows by Thursday and Friday. While storms today and Wednesday will remain isolated to scattered, any storm that develops can produce heavy rain, powerful outflow winds and dangerous cloud-to-ground lightning.
According to the National Weather Service in Tucson, atmospheric moisture will steadily increase through the second half of the week, leading to better thunderstorm coverage and a greater potential for heavy rainfall. The most significant impacts are expected Thursday and Friday, when repeated storms could trigger flash flooding and rapidly rising water in normally dry washes.
The greatest concerns extend across Tucson, Sierra Vista, Nogales, Safford, Douglas, Benson and surrounding mountain communities, where localized downpours may create ponding on roads, reduced visibility and hazardous travel during the afternoon and evening commute. Burn scars, low-water crossings and desert washes will be especially vulnerable to rapid runoff.
Motorists should expect slick roads during heavier storms and should never attempt to drive through flooded roadways or flowing washes. Hikers and campers should avoid canyons and flood-prone areas, monitor weather conditions closely and move to higher ground if thunderstorms develop nearby. Strong outflow winds may also create blowing dust in open desert areas, reducing visibility on highways.
The active monsoon pattern is expected to continue through Friday, with additional thunderstorms possible each afternoon and evening. Forecasters say the flash flood threat will be highest later this week, and additional flood advisories, flash flood warnings and severe thunderstorm warnings may be issued as conditions evolve.
