A blue sky is a good sky.

It’s a reassuring sight that promises clear weather and bright days. But what in the world does a purple sky mean?

If you’re a Vikings fan, you have to be excited. 

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The 49ers are taking on the Vikings today in the divisional round of the NFL playoffs.

The sky, seen by NBC cameras, was completely colored purple Saturday morning over Levi’s Stadium ahead of the game which will kickoff at 4:30 EST.

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