I have decided.

Wyoming weather is not only sentient, but actively malicious. And really enjoys April Fools' Day.

This morning, it was somewhat cool, but not too bad. By noon, it was actually a pretty nice day - sunny and warm enough to go without a coat.

An hour later, it was snowing. A blizzard of huge flakes.

Wonderful Wyoming...

UPDATE: Now it's bright and sunny again.

UPDATE: Now it's snowing and sunny. This is capricious, even for Wyo.