Tornado outbreak sequence of January 7–11, 2008

An unseasonably warm air mass was entrenched over much of central and eastern North America with record highs for much of the region.

[3][4] A strong low-pressure area over the central Great Lakes and its associated cold front combined with intense wind shear to provide a favorable environment for supercell development.

The hardest-hit area was in the Ozarks, around Springfield, Missouri, where nearly continuous supercells developed throughout the evening, resulting in numerous tornado touchdowns.

In addition to the tornadoes, hail larger than baseballs and damaging straight-line downburst winds as strong as 100 mph (160 km/h) were reported.

During the day, most of the activity was formed into a line that extended from the Ohio Valley to Alabama although thunderstorm-related wind damage was reported as far north as upstate New York and western Pennsylvania.

Wintry weather including snow, sleet and freezing rain on the northern side of the storm was reported from Wisconsin to Maine on January 10–11.

The storm system was also responsible for heavy flooding rains across much of the Midwest from Michigan to Missouri as well as dense fog across Wisconsin, Ontario and Quebec which was caused by rapid snow melt stemming from the January thaw.

Winds were gusting in near on in excess of 100 km/h in some localities including the Greater Toronto Area while the highest peak being 133 km/h recorded near Sandbanks Provincial Park in Prince Edward County.

Tornado tracks across Southern Missouri on January 7–8 (Courtesy of NWS Springfield, Missouri)
SPC Severe Weather Forecast for January 10, 2008, showing the moderate risk area. (Courtesy of NWS Birmingham, Alabama )
NEXRAD view of a supercell producing an EF3 tornado near Caledonia, Mississippi , displaying relative velocity on the left, and base reflectivity on the right.(Courtesy of NWS Jackson, Mississippi )
An image of a snowman taken three weeks prior to the melt.