Climate / Clima
The climate of an area is defined by the physical characteristics of the troposphere, the layer of the atmosphere closest to the earth1. Specifically, climate is related to temperature and moisture over time, as opposed to weather that is indicative of the conditions of the troposphere in the area at a given time or place 1.

The Willamette Valley climate is relatively mild and mostly resembles the Mediterranean climate which is characterize by wet, cool winters and hotter summers with moisture throughout most of the year2. These climate patterns allow for a longer growing season where there is no frost on the ground. November through March is typically wet and July through September is typically dry2. The rainfall is varied throughout the valley with approximately 40 inches in the Portland, 49 in Eugene, and up to 80 inches at the foothills of the Cascades in a year2, 3.

Climate / Clima Translation Needed

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Willamette Valley Agriculture Subtopics / Temas de Clima del Valle de Willamette


1. Miller, T.G. (2007) Living in the Environment, Fifteenth Edition (Canada: Thompson).
2. Oregon State University (1993) The Climate of tOregon Zone 2 Willamette Valley. Available at (accessed August 2009).
3. Climate Zone (2003) Eugene. Available at (accessed August 2009).

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