I checked the windchill index. Although a major storm was approaching, the temperature was predicted to be 26 degrees Fahrenheit with 21 to 28 mph winds. The index chart read from 8 to 9 degrees. Not too bad.

I then scheduled an overnight winter camping adventure for students taking my university camping and backpacking course. It happened to fall on the same night as the first major storm of the season to hit central Wisconsin on December 8, 2009. I had to make a decision as to whether or not to proceed or cancel. My top concern is always safety.

I had planned for us to camp Jordan Park just outside of Stevens Point that year, so travel was minimal. Although we anticipated somewhat high winds and a fair amount of snow, the charts predicted a reasonable windchill. Forging on, our trip proved to be challenging but safe.

That afternoon, 18 students met me on campus to pack gear for our adventure. By then it was lightly snowing. We drove to the park and hiked a short distance to three campsites along the Plover River. Now the wind was picking up and snow was flying. Our first group set up a large tarp to block the northern wind and there the entire group, in high spirits, ate supper around a campfire.

I set up my four-season tent on at the end of a small peninsula. The wind and snow blew briskly across the open water making it difficult to set up camp. A group of three students set up a tent about 30 feet from mine. They strung a rope between two trees and hung a tarp to help block the wind. I tilted a picnic table upright in front of my tent.

The wind howled wildly and continually shook my tent until I fell asleep. When we all awoke in the morning, we were greeted with nearly a foot of fresh snow for our hike out and drive back to the university. Later that day, a Wausau television station interviewed me and one of my students about our camping event during the storm.

Weather is always a concern of mine when snowshoeing and winter camping. But during winter, the elements present greater safety risks to consider than any other time of the year. To minimize the risks, I like to know about weather and prepare for it as best I can.

A meteorologist's knowledge and skills would come in handy. I am not a weatherman, but I do know that water freezes and snow can fall at 32 degrees Fahrenheit (0 degrees Celsius), and that temperatures in the low to mid 30s can result in freezing rain, sleet or snow when precipitation is present.

For snowshoeing and camping, I prefer temperatures between 0 and 30 degrees - and lots of snow. If it is too cold, it takes the fun out of the adventure. If too warm, snow can become slushy or icy.

When the temperature is minus 5 degrees or colder, I'll decline to go snowshoeing. I definitely will not go camping.

One day a few years ago, when the windchill was minus 32 degrees, I was curious what it was like outside. I bundled up with only eyes and nose exposed, walked around our yard a few times, said to myself, "Its damn cold out here," and went back inside.

Windchill is a measure of the effect of wind on air temperature, specifically how that feels on exposed skin. A helpful windchill index or chart can be found on the National Weather Service (NWS) website, www.nws.noaa.gov/om/windchill/index.shtml.

Wind combined with any amount of precipitation from a low pressure system or a front can produce a snowstorm or blizzard. The NWS considers a storm a blizzard when wind speeds are 35 mph or more and falling or blowing snow causing visibility to be less than a quarter mile.

Air pressure is the weight of the atmosphere pushing down on the surface of the earth. High air pressure usually results in cool temperatures and clear skies, whereas a low pressure system brings warm air with warmer temperatures resulting in precipitation or storms.

NWS points out that winter storms develop from three basic ingredients. The first is cold air. Below freezing temps in clouds near the ground are necessary to produce snow. The second is moisture picked up by air blowing across a body of water, forming clouds and precipitation. And the third is lift to raise moist air to form clouds and cause precipitation. This happens when warm air collides with cold air and is forced to rise over the cold air, producing a front. Air flow can also be impacted by geography and contribute to lift, especially in mountain ranges.

So where do Midwest storms often come from? From The Weather Book by Jack Williams, I know that prevailing movement of air is mostly west to east. So major winter storms in the U.S. often begin with a weather system coming off the Pacific Ocean and hitting the west coast. Once the storm dumps snow in the Rocky Mountains, it weakens. But it can regain strength as it heads across the plains east of the Rockies. The storm can then draw warm humid air from the Gulf coast and cold dry air from Canada while crossing the plains, as it reaches the Midwest with in the form of snow. Williams states that "the contrasting air masses supplies both the energy and moisture needed for blizzards."

The Great Lakes region can experience snowstorms from "lake effect snow." This is when massive evaporation of water from one or more of the Great Lakes results in the creation of clouds that move over shorelines and drops snow in nearby areas.

NWS, part of the National Oceanic and Atmospheric Administration, is a reliable source of information for planning snowshoe hikes and winter camping trips. I listen quite regularly to their broadcasts of local seven-day forecasts and other state and regional weather information. The NWS website www.nws.noaa.gov gives a five-day forecast for your area of travel as well as a wide range of other weather information.

Local television stations and their websites also offer regional weather forecasts.

Reading nature's signs for forecasts of the weather can be fun, albeit less reliable. By watching clouds I've often made predictions that proved quite accurate.

The World Meteorological Organization publishes an International Cloud Atlas with 10 basic cloud types identified by their altitude. Wispy cirrus clouds some 16,500 to 50,000 feet up are often on the leading edge of a warm front and an indication of an approaching precipitation in a day or two. Low stratus clouds that are less than 6,500 feet overhead may indicate that some moisture is close at hand.

The first thing I do to plan a day snowshoeing on a backcountry trail is check the weather forecast for the day I wish to go and check back daily for changing conditions.

Next I pack several items for convenience and safely, such as ample water and food, a candle, fire starter, matches, a portable gas stove and metal cup (for melting snow), compass and map, knife, rope, space blanket, flashlight or headlamp, whistle and first aid kit and ice grips (for crossing frozen water). I take my weather radio on winter camping, too.

Not only will I dress in layers - with a wicking layer against my skin, a warming layer next and a waterproof and breathable layer on top - I am sure to bring an extra pair of socks, hat and gloves or mittens. On overnight trips, I bring a change of clothing as well.

At the top of my gear list are my aluminum frame snowshoes and snowshoe repair kit. In my kit I have a multi-function tool with pliers, bendable wire and plastic cable clips in case my snowshoe decking clips fail.

And I don't leave home without handyman Red Green's secret weapon: a roll of duct tape.

Two primary winter risks that can occur because of weather are frostbite and hypothermia. To prevent frostbite, make you're your hands and head, including ears and most of your face, is covered. Prevent hypothermia keeping dry and warm, well fed and hydrated.

Emergency situations can occur in whiteout conditions, when the snowfall is so heavy and blowing visibility is impossible. A whiteout can leave a snowshoer disoriented and lost.

An excellent resource for managing emergency situations in cold weather is the National Outdoor Leadership School's Winter Camping by Buck Tilton and John Gookin. "It's always best to hunker down and wait it out when confronted with a whiteout," the authors advise.

If lost or needing respite from inclement weather, build a shelter with a space blanket, tarp or downed tree limbs and brush - whatever's handy. If you have snow, build a snow shelter.

High altitude sickness and avalanches are not concerns in the Midwest. But if heading west or east into mountainous areas, you should definitely consult resources and experts about safety.

One other situation for the snowshoer to be cautious of is sunlight reflecting brightly off the snow, which can cause snow blindness, a condition that can be painful and temporarily disabling. Wearing sunglasses or ski goggles will offer protection. Most people associate sunburn with summer and the beach. But snow glare can leave your face, neck and hands sunburned if exposed. Protect yourself by using sunscreen or sun block.

After putting on my modified bearpaw wood-frame snowshoes on the back stoop of my garage, I headed down the path that led into the Big Eau Pleine Flowage. We had a series of three snowstorms throughout Wisconsin one week in February 2007. As the third storm approached, temperatures were moderate.

I shoed about 50 yards out from shore heading east on our bay toward a hemlock stand. Snow in some areas on the flowage was more than a foot deep.

Ready for my return hike, I saw the storm bearing down across the frozen bay from the northwest. It was snowing hard and visibility soon became very limited. I could make out only the closest two of more than a dozen fishing shanties.

The snow let up slightly as I continued walking perpendicular to the shore so I could see the treeline on the west bank. But the north shore of the flowage, just 1.5 miles away, was still obscured.

The elements were rather harsh that day. But the hike, although challenging, was enjoyable and quite memorable. Even when my sight is compromised, I am always comforted by the swish, swish, swish of my snowshoes as I plodded along.

English novelist and playwright, J. B. Priestley wrote, "The first fall of snow is not only an event, it is a magical event. You go to bed in one kind of a world and wake up in another quite different, and if this is not enchantment then where is it to be found?"