The high desert, with its plateaus and mountains, see their share of harsh weather and sudden thunderstorms, especially in the spring and summer months. If you are hiking and see a storm developing, take precautions before the storm hits. If in a park, stop at a visitor center and check on park road conditions. Local weather can make some areas impassable.

If a thunder storm approaches, retreat to a lower location to reduce your risk of a lightning strike. If you get caught in a lightning storm, take special precautions.

• Lightning can travel far ahead of the storm, so be sure to take cover before the storm hits.
• Be especially careful not to get caught on a mountain top or exposed ridge, or near large boulders; under large, solitary trees; in the open; or near standing water; or, near telephone lines.
• If at a roadside overlook, return to your vehicle if possible. If out on a trail, don't try to make it back to your vehicle. Instead, seek shelter even if it's only a short way back to the trailhead. It isn't worth the risk. Lightning storms usually don't last long.
• Seek shelter in a low-lying area, ideally in a dense stand of small, uniformly sized trees. Never take shelter under a lone tree.
• Do not seek refuge under rock overhangs, in shallow caves, or at the base of a cliff.
• Stay away from anything that might attract lightning, such as metal tent poles, graphite fishing rods, or pack frames.
• Get in a crouch position in a low spot away from water and place both feet firmly on the ground or a foam sleeping pad.
• If you feel the tingle of an electrical charge building up, kneel down, lean forward, and place your hands on your knees.
• If you have a pack (without a metal frame) or a sleeping pad with you, put your feet on it for extra insulation against shock.
• Don't huddle together. Instead, sit 50 feet apart, so if somebody gets hit by lightning, others in your party can give first aid.
• If you're in a tent, stay there, in your sleeping bag with your feet on your sleeping pad.
• If on horseback, dismount and stay clear of the horse.
• Be alert for flash floods when it looks stormy. Do not ford low places when water is running. Flood waters can undercut pavement or sweep a car from the road. Distant downpours can cause flash flooding in areas untouched by rain.
• Never camp in a wash or a low-lying area.
• Avoid overlooks, especially those with tall trees or metal railings.

Take adequate precautions against summer heat and dust storms.

Mountain weather can change rapidly from one extreme to another. Be prepared with layers of clothing to put on or take off.

Sometimes you can anticipate weather changes by watching the clouds.

• Cumulus: They look like white cotton balls, and signal fair weather; but if these innocent clouds swell into flat-topped towers, watch out, they may become cumulonimbus thunderheads.
• Stratus: These very low, gray layers blanket the sky and make drizzle and fog. If they vanish by noon, your day will likely be clear and dry.
• Stratocumulus: Light-gray waves or ribbons with patches of blue sky between, these clouds bring light rain, but usually rise and evaporate.
• Nimbostratus: A dark gray, soggy sheet that blocks out the sun and signals a day of rain.
• Contrails: When jet trails disappear quickly, fair weather can be expected. But when they persist or expand into high-level cirrus clouds, more moisture is on the way.

Borrowed from Backpacker Magazine, September 2006.