BC0267 - Composite image of tornado and lightning in a midwestern field.

4M1831 - Canada, icicles on an iceberg in the arctic. Northwest territories Ellesmere Island.

3P6643 - Layer of Altocumulus clouds (undulatus) overtaking the sky.

3P6648 - Cirrus clouds at sunset

BB5976 - Cumulus clouds in a blue sky.

A2287A - Aurora borealis.

BM9854 - Car driving through heavy snow.

3U4209 - Cloud-to-Ground lightning.

3Y3059 - Sunrise through fog in the River of No Return Wilderness, Idaho.

6R8758 - Rain on lake surface.

6F8049 - Frozen Waterfall in Hocking State Park, Ohio.

BB5985 - Rainbow over rural Idaho. Created by sunshine on falling rain, rainbows are meteorological phenomena that cause a multicolored spectrum of light to appear in the sky.

BB9335 - Cloud to cloud lightning flashes through a stormy sky over a butte at Papago Park, Phoenix, Arizona.

3C7973 - Trail from a launch in New Mexico

BC3650 - A man struggles to walk against high wind during a dust storm in western Kansas.

BC3656 - Atmospheric scientist Scott Blair displays a handful of golf ball-sized hailstones that fell near Moses, New Mexico.

BC5426 - Sun dogs, or mock suns, are technically called solar parhelia (parhelia meaning "with the sun") and appear as bright bursts of light formed when sunlight passes through ice crystals at the proper angle. Usually, cirrus clouds in front of the sun produce sun dogs but other ice clouds may also generate them. Sun dogs are sometimes so brilliant that dazzled observers mistake them for the sun. They are often bright white but may show a partial spectrum of color with the red wavelengths on the edge nearest the sun. Sun dogs often have comet-like appearance with a bluish-white tail facing away from the sun.

BM9852 - Pedestrians struggle to help push a motorist stuck in heavy snow during blizzard conditions in Wichita, Kansas on December 22, 2007.

BT6219 - Lightning strikes during a thunderstorm on the first day of summer in Boise, Idaho.