For older football fans, watching the Minnesota Vikings play outdoors at home was a must on the weekends, especially in December. The Vikings, also known as the "Purple People Eaters," were one of the best teams in the 1970,s with Fran Tarkenton leading the way.

One of the reasons the Vikings were so successful in the 1970s was because of their stadium. They used to have one of the best home field advantages in the entire league. The Vikings played at Metropolitan Stadium from 1961 to 1981. In that 20-year time period, the Vikings made it to an outstanding four Super Bowl appearances. Although they lost all four of those Super Bowls, the Vikings were almost unbeatable at home, especially in the winter time.

Former Vikings head coach Bud Grant used to refer to Metropolitan Stadium as the "ice box." Who could blame him? The freezing cold temperatures in Minnesota would annually hit five degrees below zero (minus 10 with wind chill) creating an unbelievable home-field advantage. In 1974 and 1976 they defeated the St. Louis Rams in the NFC Championship Game, both times at home.

Tarkenton led the Vikings to three Super Bowls, while Joe Kapp was the starter in the first one. From 1968 to 1980, only once did the Vikings have a losing record before moving indoors. In 1981 the Vikings officially moved into their new stadium, the Hubert Humphrey Metrodome. With that move, the entire Vikings culture and franchise changed.

Since switching to an indoor stadium, the Vikings haven't made it to a single Super Bowl and have played in just three conference championship games. That's a far cry from their outdoor success with four Super Bowl appearances.

Coincidence? Probably not.

Oh sure, there was the whole "Herschel Walker trade" back in 1989 with the Dallas Cowboys, but every team has their ups and downs when it comes to dealing players. That doesn't even compare to this. Moving out of Metropolitan Stadium sucked the life out of the Vikings.

Playing at the Metropolitan Stadium in the '70s was one of the toughest situations for opposing players. Kicking field goals was extremely difficult, and even the elite quarterbacks at the time (Terry Bradshaw, Roger Staubach) would struggle with deep balls. But that's all gone. Having Metropolitan Stadium as your home-field was almost equivalent to the Green Bay Packers having Lambeau Field. The Packers know Lambeau Field is a huge weapon, and they will never get rid of it. Same goes for the Chicago Bears and Soldier Field.

Is it a fluke that the two teams (Bears, Packers) in the NFC North that have won the Super Bowl both play outdoors and have a combined five Super Bowl titles? On the other hand, the two teams that play indoors (Lions, Vikings) have never won a Super Bowl.

Speaking of the Lions, they (also like the Vikings) used to be great when they played outdoors. The Lions won four championships playing outdoors before moving to the Pontiac Silverdome in 1975. They haven't made it to a championship game since. Again, that's probably not a weird coincidence.

The Vikings will be moving into another dome next season, the U.S. Bank Stadium. It's a big warm and cozy stadium that holds well over 60,000 people. The players will be comfortable, which is what they want. No rain, no snow and no wind. However when the playoffs come around, and the Vikings have to travel to face a team in inclement weather conditions, they'll looked lost. An overwhelming amount of teams that win the Super Bowl play outdoors.

Since 2001, 13 of the 15 Super Bowl winners have been (you guessed it) outdoor teams.

Follow Damon Salvadore on Twitter @DamonSalvadore1