Temperatures could reach record highs in 17 different states on Wednesday, as a heat wave that has been scorching the West since last week expands into the middle of the country.

The warmth has the potential to break more than 60 records across the western half of the U.S. over the course of the day, said CBS News meteorologist Nikki Nolan. Arizona, Arkansas, California, Colorado, Idaho, Kansas, Minnesota, Missouri, Montana, Nebraska, Nevada, New Mexico, Oklahoma, South Dakota, Texas, Utah and Wyoming may all be affected, with forecasts showing temperatures rising up to, or above, 90 degrees in at least eight major cities throughout the region. 

Phoenix was expected to see the most extreme conditions, after weathering triple-digit temperatures on multiple days already since the heat wave began, according to NOAA’s National Digital Forecast Database. The Arizona capital could have a 100-degree day on Wednesday, which would exceed its daily record by four degrees. The city’s current record-high temperature for this date was set in 2022.

Other cities that may break their daily records include Albuquerque, Austin, Las Vegas, Oklahoma City, Tucson and Tulsa, each of which is forecast to see temperatures reach at least 90. Tucson could experience its hottest March 25th since 1896 if temperatures exceed 94 degrees on Wednesday, as forecasts suggest they might. Meanwhile, Tulsa could see its hottest daily temperature since 1970.

Denver and Salt Lake City could potentially break daily records set in 2012 and 2022, respectively, with forecasts indicating that the former city could see temperatures of up to 87 degrees on Wednesday, and the latter could see the mercury rise to 82.

More than 200 additional daily temperature records could be broken through Sunday, said Nolan, as the heat wave is forecast to slowly move eastward this week and eventually arrive at the East Coast on Friday. Central states are expected to see temperatures of 30 or 40 degrees above average for the time being, and Nolan warned that warmth settling into the Northern Plains will increase fire risks in that region through Thursday.

Numerous fire weather alerts were in effect Wednesday for a large strip of the central U.S., from Montana to Texas, and forecasters warned that there is a “critical threat” of fire weather through Thursday for sections of the Rocky Mountains down to the Southern Plains. In addition to the heat, wind gusts in those areas could reach up to 40 or 50 mph this week, as relative humidity is expected to drop to as low as 4% in certain places, said Nolan. Those types of dry, blustery conditions can be conducive to wildfires.