Yesterday was unique weather in the high plains for November 17, 2015. Normally, around this time of year, there can be a few scattered severe storms and even a few small tornadoes as various low pressure troughs move eastward through the high plains. However, yesterday was not normal, and was more like a full blown springtime tornado outbreak. This is quite a contrast to usual conditions of cool moderate fall weather. While a few scattered tornadoes were predicted as a 5-10% probability the day before by weather services (WXs), the main focus by most forecasters was on the possibility of a strong winter blizzard following the trough eastward, and resulting heavy snowfalls along front range upslope areas of Eastern Colorado.
There were half a dozen large violent tornadoes between Kansas, Texas, and Oklahoma. Preliminary tornado counts from yesterday, estimated by the Storm Prediction Center (SPC) is so far at an astounding 42, with a tornado also occurring later at night as far north as Nebraska. On the leading edge of the advancing low pressure trough there were dozens of tornado-warned storms being tracked in late afternoon through early evening hours. Many storm spotters posted amazing pictures of large wedge tornadoes in Texas, and Kansas. One large wedge tornado was quite visible from a long distance and from many directions near Pampa,Texas. The EF strength of this large tornado is still being assessed, and scattered late day reports indicate some manufacturing plants were likely hit by this strong tornado.
A tornado outbreak of this magnitude is not uncommon in the high plains, but is fairly uncommon to occur in mid November.
Following advance of this strong low pressure system were winter blizzards that dropped heavy snow falls and high winds across eastern Colorado, mostly affecting the towns of Burlington and Limon. Conditions were bad enough that I70 has been closed east of Denver near the Colorado border for a day, so far. CDOT road crews continue clearing deep wind drifted snow bands, and daytime heat continues to melt miles of frozen black ice roadways. Many trucks loads of magnesium chloride and gravel were seen following snow plows this evening.
Numerous storm chasers in Texas were caught surprised to be sandwiched between multiple tornado warned storms in the dark early hours of yesterday evening, and many storm trackers posted pictures of large tornadoes illuminated by lightning and power flashes.
As this strong low pressure system advances south eastward, anticipate the possibility of more tornadoes and continuing severe weather warnings will likely occur along south central States and progressing up the eastern Gulf Coast today.
