Validation of the Blizzard and Tornado Forecasts

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Blizzards are rare but events with extremely high impacts. So, it is important to validate the quality of forecasts versus what actually occurred. I also compare the tornado outlook yesterday's storms.

It is dismaying to learn of the apparently hundreds of autos that got stuck in the storm, especially to the north of Kansas. One of my motivations for presenting these validations is to convince people to take warnings seriously. I doubt that anyone on I-80 who just had to spend the night in the freezing cold would want to do it again.

Blizzard Validation
These were the early blizzard forecasts:
Posted 5:12pm Wednesday:

Posted at 9:28am Thursday. The track is a little south but overlaps the actual track.
The forecasts just got better from there. By Friday, we had pretty well locked on to the blizzard's path.

Here is the actual snow from yesterday's blizzard (yellows and oranges are snow melt).
As of this posting, they are still widening the closure of I-80 in Nebraska even though the snow has stopped. The drifting is so great and so many cars are stuck that oncoming traffic has nowhere to go. This is what some of the accumulations looked like.
Under sunny skies, this is the entrance to the Rochester (Minnesota) International Airport a little while ago. It is closed as gusts to 50 mph continue to drift the snow.

The Tornadoes
This forecast was posted Friday morning.
And, here is an incomplete (there will be more tornado locations posted as NWS surveyors do their work today) plot of tornadoes (red).
The tornado path along the Mississippi-Alabama border includes the strong tornado that struck Columbus, MS yesterday about 5:15. One died as a result. The tornado watch was timely and accurate (scroll down). There is no doubt the advance notice saved lives.

Weather science in general, and the National Weather Service in particular, deserves a great deal of credit for this outstanding performance. 

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