The cold air outbreak over the eastern United States had impacts far and wide, including the development of snow showers all the way into northern Alabama. However, between unseasonably low 850 mb temperatures and northwesterly flow, the outbreak also caused a semi-persistent band of snow to develop along the Tennessee River (downwind of a reservoir known as “Lake Wheeler”).
While most of the river-effect monitoring occurred with radar, the late-morning MODIS overpass captured one of the narrow river-effect bands (and did so more effectively than the lower-resolution GOES-East Imagery).
Figure 1. MODIS visible image, valid 1644 UTC 9 February 2016. Larger lakes are outlined in blue, and the river-effect band is circled in yellow.
Snowfall reports from underneath the band have indicated 2 to 3 inches of snow, compared to the 1-2 inches reported with heavy or persistent snow showers elsewhere. Unfortunately, orbit timing and cloud cover have not allowed us to view the snow swath using the Snow-Cloud RGB. However, the Snow-Cloud RGB from the edge of this morning’s MODIS pass still illustrated the river-effect band persistence.
Figure 2. MODIS Snow-Cloud RGB image, valid 1549 UTC 10 February 2016. The Tennessee River is the dark blue feature in the center of the image; the river effect band is circled in red.
The Wide World of SPoRT 
Yes, while driving from Birmingham on Tuesday morning – it was VERY obvious that all the fields just south of the Tennessee River were *white* – while everything South and North of there was brown. It seemed clear that it was some sort of lake/river effect – but I’d never seen it around here before.