fault zone. Because the San Bernardino Mountains are a young, steep and rapidly rising mountain range, erosion rates are extremely high and have been estimated to average as great as per 1,000 years in Mill Creek Canyon on hillside gradients as high as 36 degrees. Climate Forest Falls, in common with the rest of California, enjoys a Mediterranean climate, receiving the majority of its precipitation during the winter months, frequently in the form of snow. Temperatures are temperate, reaching average highs in the 80s during the summer, and lows in the 20s during the winter. Precipitation is higher than in the adjacent valleys and averages more than per year. Summer thunderstorms occasionally occur, particularly in the later part of the season. The amount of snow received during winter months largely depends on the area of Forest Falls under consideration, as the community extends over an elevation range of approximately . Upper Canyon, as it is locally known, that is, the eastern higher-elevation end of the community, receives on average twice the amount of snow fall as Lower Canyon. Snowfall varies, but on occasion as much as six to seven feet has been recorded, the most on average however is around one to two feet sporadically throughout the winter. See also Valley Fire References Unincorporated communities in San Bernardino County, California San Bernardino Mountains San Bernardino National Forest Sand to Snow National Monument Unincorporated communities in California