GOES-13 Water Vapor (6.5 µm) images, with hourly surface weather symbols [click to play animation]
A mid-latitude cyclone intensified as it moved northeastward across Nebraska, the eastern Dakotas and northern Minnesota (3-hourly surface analyses
) during 25 December
– 26 December 2016
. GOES-13 (GOES-East)
Water Vapor (6.5 µm) images (above)
showed distinct banding within the warm conveyor belt, a well-defined dry slot, and a large comma head that formed from the cold conveyor belt. The storm produced blizzard conditions across much of the Northern Plains and Upper Midwest, with heavy snowfall (as much as 22.0 inches in western North Dakota),
freezing rain (ice accretion as thick as 0.5 inch in Minnesota and North Dakota) ,
sleet (up to 2.0 inches deep in Minnesota)
and heavy rainfall; in Kansas there were also a few tornadoes (SPC storm reports
A noteworthy characteristic of the storm was very strong winds — a closer view of GOES-13 Water Vapor imagery with hourly plots of surface wind gusts (in knots) is shown below.
GOES-13 Water Vapor (6.5 µm) images, with hourly surface wind barbs and wind gusts in knots [click to play animation]
Note the swath of wind gusts in the 50-60 knot range which progressed across central and northeastern Nebraska into northwestern Iowa and finally southwestern Minnesota during the 02 UTC to 12 UTC period on 26 December — this was pointed out in a tweet by Anthony Sagliani as a “sting jet” feature:
As observed in previous sting jet cases (03 Jan 2012 | 28 Oct 2013), the strongest winds occurred near the curved “scorpion tail” signature seen in the water vapor imagery (which marked the leading edge of the cold conveyor belt as it advanced into the rear edge of the dry slot of the cyclone circulation).
A comparison of Aqua MODIS Visible (0.65 µm), Infrared Window (11.0 µm) and Water Vapor (6.7 µm) images at 2001 UTC on 25 December is shown below.
Aqua MODIS Visible (0.65 µm), Infrared Window (11.0 µm) and Water Vapor (6.7 µm) images [click to enlarge]
A closer view with Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1952 UTC on 25 December (below)
showed a detailed view of the banded cloud structures from Kansas into South Dakota, as well as small overshooting tops associated with thunderstorms in southeastern South Dakota and southwestern Minnesota. This storm produced the first Christmas Day thunderstorms on record in both Sioux Falls and Rapid City, South Dakota; thundersnow was also observed in Bismarck, North Dakota.
Suom NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]