Snow cover NH Source: NCAR. Source: NCAR. Climatology From climate4you.com: “Northern hemisphere weekly snow cover since January 1972 according to Rutgers University Global Snow Laboratory. The thin blue line is the weekly data, and the thick blue line is the running 53 week average (approximately 1 year). The horizontal red line is the 1972-2017 average.” [Zoom on the last years]. From climate4you.com: “Eurasia weekly snow cover since January 2000 according to Rutgers University Global Snow Laboratory. The thin blue line is the weekly data, and the thick blue line is the running 53 week average (approximately 1 year). The horizontal red line is the 1972-2017 average.” [Zoom on the last years].