That was about two weeks ago (June 24th). This was actually mild compared to other areas in Boulder.
The interesting thing is that I got to experience the development of this storm. I was in Lyons (West of Boulder, in the mountains) with friends. We got caught in an electrical storm. The electricity soon turned into a downpour! Luckily, we were able to get indoors.
About five minutes after the storm passed us, our friend got a call from another friend of ours who was in Boulder (East of us). I could overhear her on the phone saying that she had pulled over in her car because it was so bad. While I agreed that the rain was heavy, I didn't really think it was that bad. That is, until we started driving home!
It looked like it had snowed! It was incredible. The hail ripped up our trees and our garden. All of Boulder was a mess for a few days.
What is interesting about this storm is that we were able to witness what happens when you force a saturated air mass over mountains! All of that downpour (just rain) that fell on us in Lyons had to be forced over the mountains to make it into Boulder. The rain droplets got pushed up higher in the atmosphere (where it's colder) and froze! Once it got over the mountains and fell on Boulder, everything that was rain in Lyons was hail in Boulder!
Thanks to Geneva for the loverly photos! She said it sounded awful in her house as the hail beat down on her roof...