Cedar shake roofs can perform well in areas with heavy snowfall, provided they are properly installed and maintained. The natural texture of cedar shakes helps prevent snow and ice from sliding off the roof, reducing the risk of avalanches. However, it's essential to ensure your roof has adequate attic ventilation to prevent ice dams from forming. Ice dams occur when snow melts on the upper, warmer part of the roof and refreezes at the colder eaves, potentially causing water damage. Additionally, heavy snow loads can put stress on a roof, so it's crucial to have a structurally sound roof deck and framing to support the weight.