Heavy snowfall and avalanche risks stranded 13,000 tourists in a town at the base of the Matterhorn. Over 31 inches of snow fell in 24 hours, and the avalance risk has been raised to a level 5. Helicopters can transport around 100 people an hour. One local hotelier reported that authorities were setting off controlled explosions to clear away the snow. Ski slopes and hiking trails were closed a day before the storm to ensure no travelers were at risk. Conditions are expected to improve Wednesday.