On February 20th, a winter storm prompted blizzard warnings (red) for South Dakota and Minnesota, ice storm warnings (purple) for parts of Nebraska, South Dakota and Iowa, and winter storm warnings (pink) from the Northern High Plains to Michigan:
A band of heavy rain developed in Illinois ahead of the main system:
On Thursday, February 24th, this storm produced a significant severe weather outbreak across the Lower Mississippi and Tennessee Valleys:
On the north side, winter storm warnings were issued from Kansas to Maine.
The main convective hazard was from damaging wind, but some tornadoes formed on the leading edge of the squall line.
Squall line at 6:18PM CST:
Bow echo moving through the Memphis area:
Squall line at 9:48 CST:
Bow echo hitting the Nashville area, where two EF2 tornadoes were confirmed:
0Z RUC analysis had wind speeds as high as 60 knots at 925 mb, 68 knots at 850 mb, and 87 knots at 700 mb:
With winds veering about 45 degrees from 925 mb to 700 mb, helicity values were off the charts:
A RUC sounding for Memphis shows how much wind speeds increased just above the surface.
By 3Z, the 850 mb low level jet strengthened to over 80 knots, producing even higher helicity values:
The cold which hit the Southwest early this month penetrated well into Mexico causing a huge loss of crops.
The eastern coast of South Korea was hit with up to 31" of snow in one day - the heaviest in 100 years.