Tucson hit a high of 94 degrees Monday, breaking a record of 92 degrees set on this day in 1997, according to the National Weather Service.
The temperature was recorded at the Tucson International Airport.
Douglas also set a new record with 87 degrees, breaking the old record of 86 degrees set in 2004, says the weather service.
The Old Pueblo is expected to receive cooler temperatures and a chance of rain later this week, according to the forecast.
The unusual high temperatures reaching into the 90s since last week are expected to drop by Wednesday with a high of 86 degrees and a chance of showers and thunderstorms by late Wednesday night.
On Thursday, the forecast calls for partly sunny skies with a high near 68 degrees, and a 20 percent chance of rain.
The highs for the remainder of the week are expected near the mid-70s, except for Saturday, which is predicted to hit near 84 degrees.