Park rangers have recorded weather conditions at park headquarters since 1931, with only significant interruptions during World War II. Measurements of precipitation, snowfall, snow depth, and maximum and minimum temperature are made once daily around 8 AM. This data establishes average monthly weather patterns that a visitor is likely to experience anytime throughout the year.
October through June, Crater Lake National Park is generally snow covered. Snowfall averages 512 inches (13 meters) annually, and by early spring, it is common to have 10 to15 feet (4 meters) of snow on the ground. July, August, and September are drier and warmer months. A typical daytime high temperature during these three months is around 67°F (19°C), but can range from 40°F to 80°F (4°C to 27°C). Temperatures cool off rapidly in the evening, with an average nighttime low around 40°F (4°C).