Extreme heat warnings are in place for large swaths of the United States this week, as an unusual weather pattern eclipses record temperature highs.
In Billings, Montana, residents experienced a sweltering 111F (43.9C) on Sunday, the hottest day in its history. Salt Lake City in Utah also hit an all-time record high on Sunday at 109F. Boston has seen more 90F days than average, according to NPR station WBUR-FM.
