North Coast and Cascades Network Climate Monitoring Report

Climate and weather events define the ecological characteristics found in national parks and are key to understanding and interpreting changes in natural resources. Everyday park operations including fire management, natural resource activities, maintenance of park infrastructure, and visitor use are influenced by weather. Monitoring weather and maintaining climate records provides essential information to support park operations and monitor park resources. This report summarizes climate data collected within and adjacent to Ebey's Landing National Historical Reserve (EBLA) and San Juan Island National Historical Park (SAJH) from the 2011 water year. It is part of a set of climate summary reports from six national and Historical parks in the North Coast and Cascades Network. Published in the National Park Service's Natural Resource Data Series, annual climate summary reports are intended to provide basic data sets and data summaries in a timely manner, with minimal interpretation and analyses. We intend that the primary audience for this document will be National Park staff, especially decision makers, planners, and interpreters; partners; and interested public. Temperature and precipitation data are presented from four weather stations located on three islands in the northwest corner of Washington State. Data from San Juan Island (SAJH) were recorded using automated instruments operated by the National Park Service and the Federal Aviation Administration. Data from Orcas and Whidbey Island (EBLA) are provided by the National Weather Service Cooperative Observer Program (COOP). For two stations with long term records, the Coupeville COOP Station on Whidbey Island and the Olga COOP Station on Orcas Island, monthly average temperatures and monthly total precipitation are reported and compared to the 30-year normal. For the stations within or adjacent to park units, daily and monthly air temperature and precipitation data are reported. Accumulated growing degree days are presented for the Friday Harbor Airport (American Camp, SAJH) and Coupeville (EBLA). Water year 2011 had near normal annual temperatures and slightly above normal precipitation. At Coupeville and Olga, temperatures were 0.1 and 0.6 warmer than normal respectively. While annual temperature was near normal, there were large monthly deviations which balanced on a seasonal basis. Seasonal deviations were more pronounced in the case of precipitation. Spring months were much wetter than normal, while summer was much drier than normal. Total annual precipitation at Coupeville (EBLA) was 22.9 inches, 107% of normal. Total precipitation at English Camp (SAJH) was 25.3 inches.