Record heat makes for a sweltering start to October in the West

The hot conditions are expected to persist over the coming days. Dozens of heat records could be set through the weekend from California to Colorado, including in Lake Tahoe, Reno, Las Vegas, Colorado Springs and Denver.

October’s warm start follows a summer of extreme temperatures. Both Arizona and California had their warmest summers on record in 2024, according to the National Oceanic and Atmospheric Administration.

Extreme heat is expected to worsen as a result of climate change. Studies have shown that as the planet warms, heat waves will become more likely, more intense and longer lasting.

The unseasonable warmth could stick around deeper into autumn. The NOAA’s Climate Prediction Center has said there is a 50% chance that much of the West could see above-average temperatures through the month of October.

High heat extending from California into the central Rockies and the northern Plains will also increase the risk of wildfires, according to the weather service. Red flag warnings, put in place to alert for critical fire danger, are in effect in Colorado, Montana, Nebraska, South Dakota and Wyoming.