An innovative Michigan weather station. In case you have difficulty reading the sign, it says:

If rock is wet ... raining. If rock is warm ... sunny. If rock is cold ... overcast. If rock is white ... snowing. If rock is swinging ... windy. If rock is bouncing ... earthquake. If rock is gone ... weather station closed today. This weather report is brought to you courtesy of Larry's Bait & Sport

A little Michigan humor for you, I guess, but I'm betting this weather station is pretty accurate.