Blowing snow across parts of North Dakota, Minnesota and Wisconsin
GOES-16 Red Visible (0.64 µm) images from 1401-2201 UTC on 4th December, with/without plots of 15-minute METAR surface reports (cyan), Snow Squall Warnings (red polygons) and Winter Weather Advisories (purple polygons). Interstate Highways are plotted in dotted violet. [click to play MP4 animation]
GOES-16 (GOES-East) Red Visible (0.64 µm) images (above) revealed the development of Horizontal Convective Roll (HCR) clouds — a signature often associated with blowing snow — across parts of North Dakota, South Dakota, Minnesota and Wisconsin on 4th December 2024. Strong northwesterly winds in the wake of an arctic cold front were gusting in excess of 40 knots at several locations (including a peak gust of 57 knots or 66 mph in northeastern North Dakota), with blowing snow restricting the surface visibility to near zero at times. Periods of localized blizzard conditions prompted the issuance of several Snow Squall Warnings, with some of those warnings covering portions of Interstates 29 and 94 in North Dakota and Minnesota. Note that the HCRs were highly concentrated within the lower elevations of the Red River Valley along the North Dakota / Minnesota border.
Day Snow/Fog RGB images from GOES-19 (Preliminary/Non-operational) — created using Geo2Grid — provided a more detailed view of the widespread HCR clouds (below). Existing snow cover appeared as darker shades of red in the RGB imagery, while bare ground appeared as brighter shades of green; supercooled water droplet clouds appeared as varying shades of white.
GOES-19 (Preliminary/Non-operational) Day Snow/Fog RGB images, from 1421-2201 UTC on 4th December [click to play animated GIF | MP4]