Overview
- The heat peaked over the weekend with many places near or at daily records, including Phoenix around 116–117°F, Las Vegas near 115°F and inland Southern California exceeding 115°F.
- National Weather Service offices issued widespread Heat Advisories and Extreme Heat Warnings and have extended desert and valley warnings into early next week for areas such as Phoenix and the Mojave.
- Cooling centers and shelters reported surges in demand as unusually warm overnight lows limited physiological recovery and raised the risk of heat illness for people without air conditioning.
- Dry fuels, low humidity and gusty winds prompted Red Flag and 'particularly dangerous situation' wildfire alerts, a Washington state emergency declaration and regional burn bans to curb new blazes.
- Forecasters expect the ridge to weaken briefly later in the week with a chance of monsoonal moisture and small cooling, but models show the heat dome could rebuild, and long‑term warming plus El Niño are increasing baseline risk.