The National Weather Service has issued an excessive heat warning until midnight Saturday for Billings and other towns in South Central Montana, including Roundup, Hysham, Pryor, Lodge Grass, Bridger, Joliet, Hardin, and Crow Agency.
Hot temperatures of 100 degree or more will raise the risk of heat-related illnesses, the NWS said, especially in the afternoon and early evening.
A red flag warning has also been issued for South Central Montana from noon Saturday until midnight Sunday. A red flag warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior, the NWS said.
Isolated dry thunderstorms are possible Saturday afternoon and evening, and the potential for strong erratic winds will increase Sunday afternoon and evening.
In Billings on Saturday, the day will be sunny and hot, with a high around 103 degrees and areas of smoke.
Saturday night will be mostly clear, with a low around 66 and southeast wind of 8 to 11 mph becoming west after midnight.
On Sunday, there's a slight chance of thunderstorms after noon and some of the storms could produce gusty winds. The high will be near 100, with increasing clouds and hot, with a high near 100.
Look for a chance of thunderstorms before midnight on Sunday, then a slight chance of showers and thunderstorms after midnight. Some of the storms could produce gusty winds. Skies will be mostly cloudy, with a low around 62.