This application highlights changes between the 1981-2010 and 1991-2020 basin normals which are a simple aggregation of SNOTEL station normals found within or in close proximity to the selected basin.
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Caution is recommended when making inferences from comparisons between the old and new reference periods. A shift in normals may occur for several reasons including: 1) change in underlying data due to different 30-year reference periods; 2) change in calculation methods; 3) change in number of stations with official normals; 4) change in monitoring site conditions.
LOWER FLATHEAD Snow Water Equivalent Normals Comparison