I happened to look up some average temperatures a couple of weeks ago because I was talking weather with a couple other physics students and decided to compare our home-cities.  Surprisingly, in the warmest month, the average hi for all three was the same, 91 degrees.  What were the cities? St. Louis MO, Miami FL, and Lagos Nigeria.

I'll be traveling around the U.S. this summer doing bicycle tours, so I'll have my eye on the weather from Georgia to Minnesota. 

April 28:  There is a chance of snow tonight and tomorrow morning. Ridiculous, right? That got me thinking, I've seen it snow in Grinnell in 8 different months over the last four years.
The earliest: October 10 (and 11th) 2006.
The latest: May 1, 2005.
Trust me, I may not even remember waking up this morning (I actually don't, but that's the first time it's happened so don't worry about it), but I DO remember facts like this.
But here's the most impressive fact in my opinion: On July 5th, 1920, the temperature here fell to 29 degrees.