Mar 23, 2013

Christmas Tornado Outbreak

On Christmas Day 2012, a storm with a surface low of 996 as far south as central Mississippi produced a tornado outbreak from Texas to Alabama.

 Numerous injuries were reported, but no fatalities. Mobile, Alabama was hit by an EF-2 tornado just 5 days after an EF-1 hit almost the same area. Track for the December 20th tornado:
Track for the Christmas tornado:
 Looking at the video of the Christmas Day Mobile tornado, it is surprising that it was only rated EF-2.

Water vapor and radar imagery of the storm:



Analysis charts for 21Z (3 PM) on Christmas (Mobile tornado was at 5 PM) show strong jet stream splitting at 250 mb, a 60 knot low level jet, dew points in the upper 60s, 2,000+ CAPE, and 300+ 0-1 km storm relative helicity over the Gulf Coast.








This same storm prompted blizzard warnings from Arkansas to Cleveland, and winter storm warnings from Texas to Maine:
8.5 inches of snow fell in Texas (De Kalb), 13 inches in Arkansas (Morrilton), and 27 inches in Vermont (Woodford). A snowfall map is available here.