← Latest briefing

Environment & Climate

Excessive heat expands across central and eastern U.S. as flash floods hit Southwest

High temperatures and humidity are forecast to stretch from the Plains to the Mid-Atlantic, while monsoon storms prompt evacuations in Arizona and Utah.

The short version

  • Dangerous heat is spreading from the Southwest into the Plains, Midwest, and Mid-Atlantic, with heat index values expected to reach or exceed 100 degrees in several major cities through early September.
  • Nighttime lows will remain in the 70s across parts of the southern Plains and Mid-Atlantic, offering minimal overnight temperature relief.
  • Monsoon-driven flash floods in the Southwest triggered home evacuations in Utah and air evacuations of dozens of people in Arizona's Grand Canyon National Park.

Key facts

  • Heat index values are expected to hit or exceed 100 degrees in cities including Kansas City, Des Moines, Chicago, Charlotte, Raleigh, Richmond, and Washington, D.C.[ABC News]
  • The National Park Service air-evacuated 62 people from the Phantom Ranch area of the Grand Canyon by Sunday morning following Saturday flash floods.[ABC News]
  • Flooding along Cottonwood Creek in Orangeville, Utah, forced the evacuation of multiple homes and apartments.[ABC News]
  • Flood watches were issued for portions of Arizona, Utah, and Colorado, covering cities such as Phoenix, Tucson, Flagstaff, Cedar City, and Grand Junction.[ABC News]

What remains uncertain

  • The status of over 20 individuals listed as unaccounted for or missing by the National Park Service following the Grand Canyon flash flood remains unverified.[ABC News]

Sources