Clear Skies, VIIRS and the Great Lakes
VIIRS data from NOAA-20 at the CIMSS Direct Broadcast download site, above, at 1734 UTC on 2 September were used to create True Color imagery, and SST fields over the largely-clear Great Lakes. Light winds associated with persistent high pressure over the Great Lakes (below) meant suppressed vertical mixing, leading to warm water temperatures on the lake surface. Most of Lake Superior’s surface is warmer than 60oF, with portions of Lake Erie, Saginaw Bay, and Green Bay near 77oF. This is also shown in the AWIPS Screen-capture with the same data, below.
Early on 1 September, skies were also mostly clear, and the VIIRS ACSPO SSTs are shown below in concert with Day Night Band visible imagery. The warmest temperatures in the color enhancement (white) are 77oF (that is, 25oC).
Clear skies continued overnight on 2-3 September, and another beautiful scene was produced. Lake Surface Temperatures and the Day Night Band at 0740 UTC on 3 September are shown below.
True-Color imagery from VIIRS and Lake Surface Temperatures are shown below from 1834 UTC on 3 September. Note the complete coverage over western Lake Superior. The anomaly in the analysis above has been rectified. Smoke is also apparent in this image over northern WI and central MN.
The smoke shows up well in the VIIRS AOD field, below (and in the GOES-16 fields as well here)
