Oregon has a relatively mild climate, largely affected by the Pacific Ocean and the Cascade Mountain Range. West of the mountains, the Pacific Ocean keeps temperatures moderate and precipitation more plentiful in the winter. East of the mountains, less rain and cooler temperatures are the rule during winter.
Summers throughout the state are typically dry and sunny, states the Oregon Climate Service. On the western side of the state, precipitation averages 40 to 50 inches per year during the rainy season that stretches from October to March. Central and eastern parts of the state are drier year round. Temperature ranges are potentially severe in Oregon, a state that has reported an all-time low of -54 degrees and an all-time high of 119 degrees, though such extremes are not common.