The weather at Crater Lake interests park visitors and employees alike. Everyone has their idea about what is "normal" when it comes to precipitation, whether it is rain or snow. Much of the literature about Crater Lake and its "averages" is dated and therefore inaccurate. Incorporation of recent data into calculations based upon the park's weather records reveals some significant changes with respect to what we consider average.

Yearly precipitation averages were recalculated on December 31, 1991. Data from 63 years of records shows an annual average for precipitation of 64.31 inches. It is more accurate, however, to use only the totals recorded since 1930, when the weather station was moved from Annie Spring to its present location at Park Headquarters. The average for the 56 years of complete records at headquarters is 66.8 inches. (Data for the years 1930, 1942, 1943, 1944, 1945, and 1946 is not available). The "new" average is more than two inches below the "old" average of 69 inches, which is a figure based upon a 30 year running mean calculated by the U.S. Weather Service.

Yearly snowfall averages were recalculated at the end of the snow year, July 1, 1991. Beginning with the winter of 1930-31, and ending with the 1990-91 winter, the yearly average from accumulated snowfall is 533 inches. (This was obtained from 57 years of data, as the period of 1943-46 is not available). The "new" yearly average is 44.42 feet, significantly below the 600 inch and 50 foot figures that have been used to characterize snowfall at Crater Lake.

One should also be cautious in regard to equating "average" with "normal". Crater Lake is in southern Oregon, a region whose climate more closely reflects the eccentricities of northern California's Mediterranean regime than the temperate conditions found north of Diamond Peak. Dry cycles lasting a number of years are par for the park, both in the recent and geologic past. These droughts can be suddenly interrupted by "wet" years which may keep the park snowbound well into July or August. An enormous snowfall during one or several years has the effect of adjusting averages upward of course, sometimes planting a deceptive image to people who have not looked further than the overall average of 533 inches. What is really "normal" is variation.