Lake/river effect clouds in North Dakota
* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *As cold arctic air continued to move eastward across North Dakota on 07 November 2017, GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) showed “lake effect” cloud plumes streaming east-northeastward from Lake Sakakawea (and also from Missouri River). The Snow/Ice images were the most useful for discriminating between supercooled water droplet cloud plumes (brighter shades of white) and the surrounding snow-covered land surfaces (darker shades of gray).
During the preceding nighttime hours, Suomi NPP VIIRS and Aqua MODIS Infrared Brightness Temperature Difference images (below) — the legacy “fog/stratus product” — revealed that the orientation of the Lake Sakakawea cloud plume changed as surface winds switched from northwesterly to westerly.
The Aqua MODIS Sea Surface Temperature product (below) indicated that the water in Lake Sakakawea was as warm as 47.9ºF (darker green enhancement) — significantly warmer than the surface air passing over it, which was generally in the 5 to 15ºF range. The large cloud plume from Lake Sakakawea was also very evident on GOES-16 Day Snow-Fog Red-Green-Blue (RGB) images (below). Farther to the east, smaller and shorter-lived cloud plumes could also be seen originating from Devils Lake (along the Benson/Ramsey county line) and Stump Lake (in Nelson county). Taking a closer look at the Lake Sakakawea area, the brighter signature of steam plumes rising from power plants located south and southeast of the lake (2 in Mercer county, and 1 in McLean county) could be spotted on the Day Snow-Fog RGB images (below). Due to the low sun angle and the snow-covered land surface, morning shadows from these rising steam plumes could be seen on GOES-16 “Red” Visible (0.64 µm) images (below). Special thanks to Carl Jones (NWS Grand Forks) for bringing this case to our attention, and supplying the AWIPS RGB and Visible images at the bottom of the blog post.