Snow Rules!
Enhanced Snow and Precipitation Monitoring within Minnesota Portions of Watersheds Draining to Lake Superior
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Snow Rules! Enhanced Snow and Precipitation Monitoring within Minnesota Portions of Watersheds Draining to Lake Superior |
To make the best use of data, each month of snowfall was analyzed to a grid of values for the region. Those monthly grids were then summed to form the pattern shown above. The formation of grids of snow was guided by the use of elevation and the distance to Lake Superior. In that way even in areas where data is still somewhat sparse the steep ‘gradient’ of snowfall values, up to about ˝ foot per mile, from shore to inland could be shown.
Data was provided by 67 Soil and Water Conservation District Observers plus 21 National Weather Service and DNR observers (in St. Louis, Lake, and Cook counties).
The blue dots, representing individual observers, show the average fraction of the median of the event's non-zero snowfalls. The green line is a type of weighted running average of the individual observer values. An overall peak occurs approximately 8-10 kilometers inland. That distance is where the land surface has climbed about 75% of the height difference of the inland highest surfaces and the Lake Superior. On the average the highest elevation of the land surface occurs at about 25 km inland. The location of that snowfall approaches the elevation peak but still on the upslope side is what was expected.
The graph can be stretched logarithmically so that the observers nearest the shore
are more spread out in the graph.
