North Coast and Cascades Climate Monitoring Report

Climate and weather events define many of the abiotic features of habitat found in national parks and are key to understanding and interpreting changes in natural resources. Everyday park operations including; fire management, search and rescue, 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 in the North Cascades National Park Complex for Water Year 2010, and is part of a set of climate summary reports from seven national and historic 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 envision National Park staff, especially, planners, scientists, interpreters, partners; and interested public as the primary audience for these reports. Temperature and precipitation data are presented from six weather stations. These stations are located on both western and eastern slopes of the North Cascades Range at both low and high elevation sites. Data were recorded using automated instruments operated by the National Park Service and other collaborators, including the National Weather Service (NWS) and the Natural Resources Conservation Service (NRCS). For two stations with long term records, the Ross Dam Cooperative Observer (COOP) station on the west side of the Cascade crest and the Stehekin COOP on the drier, east side of the park, monthly average temperatures and monthly total precipitation are reported and compared to the 30-year normal. Monthly snow depth and snow water equivalent are reported for one Snow Telemetry (SNOTEL) site and two NWS COOP stations within the park. Two NPS GLACIER climate stations provide air temperature at high elevations in alpine environments. A NWS US Climate Reference Network (USCRN) station located in Marblemount represents lowland areas on the west slopes of the North Cascade Range. A series of appendices present daily and monthly air temperature, precipitation and snowpack data from six park operated weather stations, including comparisons to period of record and highlights of important weather events from each site. In summary, average annual temperatures and precipitation were both near normal for Water Year 2010; however significant monthly departures for both parameters were documented. Overall, conditions in winter were warm and dry, with a shift to cooler and wetter conditions in the spring through early summer. Snowpack remained below normal during the warmer, drier winter months only to recover to above normal due to a wetter, cooler late spring that persisted into late June.