Heavy to excessive monsoon rainfall forecast over the Desert Southwest, isolated flash flooding risk
Heavy to excessive rainfall from monsoon thunderstorms may bring isolated flash and urban flooding to the Desert Southwest into Sunday, September 28, 2025. A plume of anomalously high monsoonal moisture streaming northward on the eastern flank of a slow-moving upper-level low will fuel several rounds of widespread showers and thunderstorms, with greatest impacts expected across southeastern Arizona and southwestern New Mexico.










