I found this on a Kansas newspaper website and thought I'd share. I've always wondered why the sky turns green before a tornado, and I also remember someone posting about this recently. I think it's cool! (It's written by a weather guy)

Green skies

Over the years I have often heard people speak about the sky turning green before a particularly bad storm. Sometimes those storms produce tornadoes. But the tornado isn't what causes the sky to turn green. The color magician is the hail in the thunderstorm. As light from above travels through the storm, it is reflected and refracted by the water droplets and hailstones. The hail allows more of the green to get through, giving the clouds that hue.

By Colette on Friday, June 4, 2004 - 04:09 pm:

We rarely have tornadoes in New England, but this is what the clouds looked like yesterday afternoon. It went from absolutely beautiful to pitch black within 25 minutes. And then we had the strangest looking clouds. Here is what they looked like http://www.newburyportnews.com/

By Amecmom on Friday, June 4, 2004 - 04:11 pm:

Thankfully, I've never seen this phenomena, but it sounds really cool - unless you're the one expecting the tornado.
Ame

By Kaye on Friday, June 4, 2004 - 06:03 pm:

I think the imporant thing to get from this message is green clouds equal hail! Yes that type of storm can have a tornado, but hail damage is a huge pain. I grew up in west texas where this happened more than once, you literally could see it coming. Thankfully most of the time we have 30 minutes or so to ready things up, like park the cars inside, etc.