PRELIMINARY: Two people were clearing snow from a low-angled roof. The snow avalanched. Both were caught and buried, but no one witnessed the avalanche. About 10 minutes later, someone discovered the avalanche, called 911, and began digging. Local emergency services personnel arrived within 10 minutes. The first person was dug out and survived. The second person was buried more deeply. They were located by probing, and were not breathing when dug out. The two were buried for 20 to 30 minutes.