In honor of Severe Weather Awareness Week, I'm going to talk a little bit about severe storms and what exactly the threshold is that makes a storm severe. I'm not, however, mentioning all of this because there's any severe weather on the way. So don't freak out. Everything's OK.
For a storm to be labeled "severe," it's got to meet any one (or more) of these three main criteria:
1. Hail in excess of 3/4" in diameter
2. Wind gusts of 58 mph or greater
3. Tornadoes (duh)
That last one always gets me. Really? A storm producing a tornado is severe? Are you sure? Funny stuff.
I think the storm parameter that gives people the most confusion is the hail criteria. Just because a storm is producing hail doesn't necessarily make it severe. Strong, yes, but not strong enough to cause any damage. That said, whenever a storm is producing hail (even pea size), it's certainly not a bad idea to seek shelter (not that you'd be out for a stroll in the middle of a hailstorm- I'm talking more about if you're driving).
So if a storm meets any one of the criteria mentioned above, a warning is issued for it. In Eau Claire county, storm sirens will sound for either tornado or severe t-storm warnings; however, that isn't the case in other counties around the area. If you've got any question about the policy in your county, you should call your county's emergency management department to get that cleared up. And if you live in an area where you can't hear the sirens, consider getting yourself a weather radio. Better safe than sorry, right?