Strange Weather. Dry as a Desert, air pressure falling!?

I don't understand why. Why? Because well there's supposed to be an exceptional high pressure over the Midwest. And it's as dry as desert, as you can clearly see by the following info . But what is this info? Although you can't see it, this is the current state of Michigan, specifically our local area here in the South Eaton County. It is well, strange, though am I right?!