REGINA – If for no other reason, this Sunday’s Grey Cup game in Regina will be unique simply because it is being played outdoors. The last two Grey Cups, in Toronto in 2012 and Vancouver in 2011, were played under the warm, friendly confines of a dome where weather was not an issue.

That is definitely not the case this week in Regina. On Thursday, the temperature reached -20C with a wind-chill of -30 as the teams practiced at Mosaic Stadium. It is so cold in Regina this week that organizers are even considering cancelling some festival events.

The Hamilton Tiger-Cats practiced outdoors on Thursday, and some players even suffered frostbite. The Saskatchewan Roughriders practiced indoors on Wednesday before moving outside on Thursday.

Slotback Kierrie Johnson is in his first season with the Roughriders after spending two with the B.C. Lions. He said Thursday's practice was the coldest conditions he's ever played in.

"It was pretty cold. A couple guys came out, no sleeves. Some people can tolerate the cold better than others. I layer up, I wear about three layers," the Houston native said.

The forecast for Sunday doesn’t look too bad, though. By game time it’s supposed to “warm up” significantly to a high of zero and a low of -9.

But if that so-called warm front doesn’t come in time, the 101st Grey Cup could enter the record books. Here are the seven coldest Grey Cup games on record:

7. 65th Grey Cup, 1977 – Olympic Stadium, Montreal: -9, frozen field

The Montreal Alouettes beat the Edmonton Eskimos in the infamous Ice Bowl. The brand new Olympic Stadium didn’t have its roof added until 1987 and at game time the turf was like a sheet of ice. The Alouettes gained an advantage by putting staples in their shoes.

6. 37th Grey Cup, 1949 – Varsity Stadium, Toronto: -9, snowing, muddy field

The Alouettes won their first Grey Cup, beating the Calgary Stampeders, in the coldest of many Grey Cup games played in Toronto.

5. 72nd Grey Cup, 1984 – Commonwealth Stadium, Edmonton: -10

The very first Grey Cup game in Edmonton was played in -10 degree weather as the Winnipeg Blue Bombers beat the Tiger-Cats.

4. 63rd Grey Cup, 1975 – McMahon Stadium, Calgary: -10, cloudy

The first Grey Cup game held in Calgary, and only the third to not have a touchdown scored. The Eskimos beat the Alouettes 9-8.

3. 21st Grey Cup, 1933 – Davis Field, Sarnia: -10, snowing, frozen field

The Toronto Argonauts beat the Sarnia Imperials 4-3 on frozen field.

2. 19th Grey Cup, 1931 – Molson Stadium, Montreal: -11, snowing, frozen field

On a cold day in Montreal, the Montreal AAA Winged Wheelers became the first team from outside Ontario to win the Grey Cup. They beat the Regina Roughriders 22-0 in the first Grey Cup game that allowed the forward pass.

1. 79th Grey Cup, 1991 – Winnipeg Stadium, Winnipeg: -17, sunny

In the coldest Grey Cup ever, the Argonauts beat the Stampeders 36-21. It was fitting end to the first season under new owners Wayne Gretzky, John Candy, and Bruce McNall.

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