We usually have a lot of storms in the Midwest, although this year has been a dry one.
Thunderstorms are pretty common here. I used to really love being outdoors and watching the lighting snake across the sky and feeling the roll of thunder, but when I was shocked by lightning in 2006 it's been a fear of mine. Nowadays, I react less severely. I think thunder is still really cool if it doesn't sound like a bullwhip. (It did that once this summer while I was on someone's porch and the next thing I knew I screamed and crouched with my hands over my face.) 

 Like others have mentioned, the rain will pour down so hard and in great volume that your vision is quite limited. Hail can also accompany a thunderstorm. We've had hail about the size of a quarter that I've seen. My friend's dad brought back a piece of hail the size of a softball from a city an hour north of us! That can be really dangerous because with hail that size, it was taking out people's windshields (or windscreens for the Europeans 

 ). 
The month of May, I believe, is tornado awareness month so the city sounds the sirens and tornado warning tests every Wednesday that month. The rest of the summer the sirens only go off twice on the first Wednesday of every month. 
I've never seen a tornado, but know one was only a few miles out of town. The sky, in that case, did indeed turn a strange shade of avocado-like green with foreboding puffy black clouds. When there's a storm like that, the wind will rip across the land with great force and then suddenly is will stop and all will be still. It's incredibly eerie. The wind will usually pick up again but blow in the opposite direction.
Droughts aren't fun because dust is everywhere and everything is covered in it. At least in the farming communities like the one I live in. The dirt cracks open creating little canyons throughout the garden and the plants all wilt and die.
On the opposite side of the spectrum too much rain can be a problem too. Last year we had lots and lots of snow. My dad had to help the city plow and he would work all night moving snow from hospital parking lots and commercial businesses. When spring came it all melted, creating flooding and the plentiful rainfall didn't help the situation. Farmers were all trying to tile their fields to drain the water from it because the rain water would sit stagnant in the fields drowning their crops. It flooded out parts of cities and took out land bridges.
 That's all I've got for tonight...er this morning. 

~Calen