Cottage Grove’s climate is largely controlled by maritime air from the Pacific Ocean and periods of extremely hot or cold weather are usually short lived. The average high temperature in July and August is 83 degrees. Average low temperatures on summer nights are in the 50s. The coldest month is January, with an average low of 35 degrees and highs in the 40s. Cottage Grove’s elevation of 641 feet and our mild weather gives us an average of 268 frost-free days each year and an average of 269 sunny days. Annual precipitation is 46 inches of rain.
Oregon has a reputation for heavy rain, but Cottage Grove’s annual rainfall is actually the same as in the Great Lakes, northeastern and New England States, and less than is typically found in the southeastern states. There are almost no thunderstorms, and rain tends to be gentle enough not to disrupt most outdoor activities. In winter, early morning fog and overcast skies are common. Summers are sunny and dry, with rain on only three or four days in July and August. Snow is rare, but the nearby mountains accumulate a snowpack that enhances the view from the city and provides winter recreation areas close at hand.