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Abstract
This report describes the primary meteorological station at the H.J. Andrews Experimental Forest (elev. 426 m, lat. 44°15' N., long. 122°10' W.) in the Willamette National Forest, the automatic digital data logger, sensors, and data-processing procedures used in measuring air temperature, dewpoint temperature, windspeed, precipitation, and solar radiation. The quasi-Mediterranean climate has mild, moist winters and warm, dry summers. Average daily air temperature in July is 17.8 °C; in January, 0.6 °C. Six percent of the mean yearly rainfall of 230.16 cm falls from June through August. July is the driest month, with an average rainfall of 1.76 cm. Seventy-one percent of the precipitation falls from November through March. December is the wettest month, averaging 42.31 cm. The average number of days between the last spring frost and the first fall frost is 134.
Citation
Bierlmaler, Frederick A.; McKee, Arthur. 1989. Climatic summaries and documentation for the primary meteorological station, H.J. Andrews Experimental Forest, 1972 To 1984. Gen. Tech. Rep. PNW-GTR-242. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 61 p