Denverites face a possible 101-degree day on Friday before a strong cold front cools things down to a high of 78 by Sunday, National Weather Service forecasters said.

If the mercury climbs to 101 degrees at Denver International Airport Friday afternoon, as Boulder forecasters predict, it will tie an all-time heat record for July 19 set in 2005, the NWS said. If it gets that hot it will be 11 degrees above the normal of 90 degrees for July 19. DIA is where official Denver temperatures are recorded.

It would also be the third gruelingly hot day in a row in which heat records were tied or beaten.

Denver topped out at 99 degrees on Thursday, which tied a heat record set in 1998. On Wednesday, the city broke a minimum warmth record when it didn’t get below 72 degrees the entire day.

Hot and mainly dry today with high temperatures around 100 degrees! Relief coming for the weekend. #cowx pic.twitter.com/EuKQ3nK8Qz — NWS Boulder (@NWSBoulder) July 19, 2019

But because Colorado’s weather has a way of being topsy-turvy, temperatures are expected to drop significantly when a cold front moves into the state on the weekend.

On Saturday, the high temperature is expected to be about 84 degrees, or 6 degrees below normal for July 20. On Sunday, temperatures aren’t expected to climb past 78 degrees, or 12 degrees below normal for July 21.

There’s a good chance for afternoon rain and thunderstorms throughout the weekend. On Saturday, there is a 50 percent chance for rain and on Sunday there is a 40 percent chance.

Even though the chance for rain increases to 60 percent on Monday, the high temperature is expected to surpass weekend highs by reaching about 85 degrees, the NWS said.

Denver high’s will reach the lower 90s Tuesday through Thursday, forecasters said. Rain and thunderstorms are possible each of those days.