When my daughter was little, she had a nightmare-inducing fear of hurricanes -- irrationally so since we live in Chicago and, while Lake Michigan is big, it is but a lake. Now a tornado? Well...
Fast-forward 15 or so years and the truth is I think we're all a bit undone by the weather. A devastating tornado will do that. Who but the most stoic among us isn't scared witless by such raw power?
But more unnerving than one single event -- or even a collection of them -- is the eerie knowledge that, with climate change, the heavens are out of whack and new weather patterns are wreaking havoc. With each passing season we learn that the unusual has become the expected.
Yesterday, USA Today shared the depiction of Tornado Alley below. It looks so innocuous, for those of us sitting outside the red zone, doesn't it?
Where Is Tornado Alley?
Source: National Oceanic and Atmospheric Administration, Storm Prediction Center, K.M. Simmons, D. Sutter and R. Pielke Jr., "Normalized Tornado Damage in the United States: 1950-2011" (as presented by Janet Loehrke, Frank Pompa, Jerry Mosemak, Tory Hargro and Anne Carey, USA Today)
Don't be fooled:
...but where once most Americans could watch the danger and drama of a big, killer twister with a certain detachment, changes in weather, demographics and culture have all but obliterated such a comfortable remove.
Literally and figuratively, Tornado Alley now could be almost anywhere; the alley is more like a field that seems to spread by the year.
As analytical people, we turn to the data to help us make sense of it all. Unfortunately, what I found by clicking around the National Weather Service's National Weather Hazards map below did more to alarm me than to settle.
National Weather Hazards
As of 5 p.m. ET Tuesday, this National Weather Service map showed parts of Arkansas, Louisiana, Mississippi, Tennessee, and Texas in a tornado watch zone, as denoted in yellow (key available here).
You see that little bit of neon green in Illinois, just beneath Lake Michigan? It's a flood warning, and I made the mistake of clicking on it. And one or two layers in I found this rather dire forecast from the NWS:
It is not a question of if but when Chicago, Rockford, and nearby areas will see a violent tornado. Much of northern Illinois and northwest Indiana has not seen such a tornado in many years, and especially an outbreak of significant tornadoes. But no one should be complacent because of that, as climatology indicates it certainly can happen.
If we can place stock in historical data, we can assume the impending tornado will occur in the spring or in the late summer through mid fall; hit in the early afternoon or evening; and, we can only hope, be on the lower end of the F-Scale used to rate the intensity of a tornado. F2 tornadoes have been the most prevalent in the Chicago area, although about a dozen F3 and F4 tore up the land between 1855 and 2008, the NWS reported. Of little comfort is that only one F5 tornado ever crossed the Chicago area -- a fatal twister that hit in late August 1990, killing 29, injuring 350, and causing $165 million in damage along a 16-mile path.
Chicago-area Tornado History
The F-Scale, as noted in this National Weather Service graphic, denotes tornado intensity.
One of the last times the NWS issued a tornado warning in my area, I was heading home from an evening swim with my kids in tow. In the space of two miles, the weather turned from mild to violent, with torrential rain blowing horizontally against the car at one point. Was I scared? You bet. Did I feel prepared? Not in the least. But once curbside, and as a lull came up, we made a break for the house, headed to the basement, and made an adventure out of it.
Now that I've dug around a bit in local and national tornado data, do I think I'd be any more prepared than I was then? Not so much. Frankly, the data is scary.
For a calming affect, though, what I will do is call to mind this data visualization on tornado strikes that's been circulating of late. I don't know why I find it soothing, but I do. Maybe it's a reminder to stay calm amid the powerful force of nature.
A map of tornado activity in the U.S., 1950 to 2011. Photo: John Nelson / IDV Solutions
I'll take the one further and say that good information and good communication are key. One of the reasons there were so many issues with New Orleans when they were hit with their last big hurricane was that no one listened to the warnings. Everyone was more or less numb to the forecasts because they kept hearing the same thing every time a hurricane was close. We saw the same thing here in central FL about 6 years ago. We had 3 direct hits within the span of a few months. The first one had the highways packed as people moved to safer areas. They the time the third one hit no one was moving because it was old news and we'd already made it through two others.
Living in the footprint of "Tornado Alley" and "Hurricane Lane" I can't stress the importance of safety and communication. Several of the more recent disasters have become PR nightmares because of the breakdown of communications and prevalent safety issues for citizens. These two issues are paramount in disaster response.
It does make you wonder if it was a legitimate pattern or if this is an example of selection bias. Before radar and meteorologists people watched cloud patterns and the direction of the wind to predict storms on the horizon so it's not totally dismissible but I do wonder if it's just a matter of a vocal individual who just happened to get a prediction right.
@SaneIT, thought I'd share one last note on tornado forecasting. I read this nice human interest story about an Oklahoma weather forecaster who, apparently, is quite well trusted in Tornado Alley:
"Two days before the tornado hit, Gary England had an uneasy feeling. The wind patterns emerging over the weekend reminded him of the conditions that unleashed deadly storms in the region on May 3, 1999.
He began warning that trouble was just days away. England has been forecasting the state's often capricious weather for so long — 40 years — that when he says to seek shelter, they do."
Well that covers tracking them once they form but NOAA has already predicted how many major storms they think will form out over the open ocean. They are usually pretty close with that number. Not hurricane models on the other hand can vary wildly and the paths that they predict can be hundreds of miles off but I'm thinking more along the lines of just knowing roughly when and how frequently they will form.
Lyndon it really is like a movie. I have spent a good portion of my life on the East Coast and the weather is defintely getting frightening and out of context. We had the heat on this Memorial day weekedn temps were hitting lows in the 40s for the beginning of summer! The analytics of our weather patterns and their evolution will certainly be interesting reading over the next few years.