Overpasses are bad, m'kay?

We are all susceptible to wrong thinking- one could say it’s fundamental to what makes us human- and I’m no exception.  I do pride myself on generally knowing whether an idea is coherent or not (something I’ve worked very hard at), but I make occasional (read: lots of) mistakes.  Last night could have killed me, so I guess it was more than your usual misinformation (whether I believe in Bigfoot is seldom life threatening) or even the more practical knowledge (knowing when a so-called “business deal” is a scam).

The double rainbow I saw.

I suppose I should set the scene.  I live in Altus, a small town in southwestern Oklahoma, and I frequently have medical appointments that the local area can’t field, so I have to drive for about an hour to get to Lawton, a slightly larger small town that manages to pass as a city (no offense, well, not too much offense to my Okie friends).  Yesterday afternoon, there was a warning that there might be hail in the area, and when I looked at the weather radar, there was a heavy storm coming right for us.  I figured if I left immediately, I should be able to stay just ahead of the storm.  On the way, my supervisor called to tell me that a tornado had touched down, just outside of a small town and the highway I was on.  I had literally passed the town 4 or 5 minutes before, but besides the ominously dark clouds behind me, it was clear in front so I pushed on.  I heard one of my favorite songs, Avenged Sevenfold’s Nightmare, on the radio and saw a perfect 180 degree double rainbow (the second in my life!) and escaped the downpour with only a few miles of rain, which would last most of the day for home- it was a great ride.

I arrived at my destination unhindered at about 3:30 PM, but I still knew I’d dodged a bullet earlier.  I don’t believe the tornado did cross the highway, but it could have.  By the time my appointment was over, the weather had passed over, but was still all along the route back home.  So I decided to hang out in town until things looked better outside.  By the time I left, it was 9 o’clock at night.  I felt 5 hours would be plenty of time for the storm to get out of the way, and never bothered checking my weather app.  For those keeping score, this was my third mistake that day.

I am usually a fan of night driving, but this time, it would prove to be a bad idea.  Daylight Savings Time had just ended, making it much darker than I’d planned, such that I can’t tell what the clouds look like.  There’s no rain and very little lightning visible.  So I start the 50 mile drive.  After 10 miles or so, the lightning has steadily been increasing, but I can’t see any bolts or hear thunder, which means it’s far off, and mostly to the North.  As it’s not too threatening, I press on.  I get about 15 miles in, and the clouds start to drizzle- nothing that I even need to put my wipers for, but the lightning continues increasing in frequency, and the wind picks up, still blowing from the south southwest.  It’s perfectly normal to be driving along in Oklahoma and the wind just decides to blow you off the road, so that wasn’t alarming in the slightest.  Then at what had to be about 20 miles in, a wall of water hits my car from the South.  My wipers are on full bore and I still only get glimpses of clarity before they’re filled in by more water.  I slow down, which I almost never do for rain, but I felt myself hydroplaning, and the water on the road looked deep- we’re prone to flash floods, and this could turn into one, though probably not enough to float my car, enough to push it off the road.

So, driving along at 35 Mph, I make it another 5 miles or so.  It could only have been about 10 minutes before the rain abruptly stopped, but in that time the wind changed direction twice, blowing straight back toward me (East), and then switching to blowing towards the south.  That was when I started getting nervous.   Then, lightning bolts, now clearly visible, were in front of me.  For a split second, I see what could have been a funnel cloud highlighted to the northeast- and I start watching the skies.  At least in the day, you have a clear view of what the clouds are doing, and I just have to wait for an opportune lightning bolt to strike behind it.  It didn’t take long- and sadly, I wasn’t disappointed.  It wasn’t a full funnel yet, but it definitely appeared like a semi-triangular cloud formation, pointing down in a horizon that was otherwise featureless.

Now I’m very nervous.  My instinct says to find shelter, to put something between me and it besides my car.  I know the route (and by route, I mean 50 miles of straight, mostly featureless road), and I know that just a few miles on, near the town the tornado touched down, there’s an overpass where another state highway crosses.  I figure if I can just push toward that, I can ride it out.  This is mistake number 4, maybe 5 if you count not turning around when it started getting worse; 6 if you count trying to come back that night at all.  I’ll go with 6.

So, I make it to the overpass uneventfully, but I keep watching that-spot-in-the-sky-where-I-saw-what-might’ve-been-a-funnel-cloud-forming.

And then I just wait.  The rain had returned, the wind had changed directions a few more times, and it was moving fast enough to blow the rain sideways.

I remember thinking, wouldn’t this bridge make a sort of funnel?  I knew tornados were often very wide- larger than the bridge in every dimension- but I figured, at least with cover, I’d have a better shot.  After all, the vacuum is above you, so you should get pulled up, mostly, right?  I waited, hoping things would get better.  They got worse, but I just kept alternately listening to the radio and listening for the sound a tornado makes.  I’ve been told it sounds like a train blasting by, a high pitched roar.  I figured, if I heard it, I’d get out and hide under the car.  I spent some time in the back seat, belted in as well.  I had no idea what to do, and was mostly trying to occupy myself by thinking I was doing something useful.  The bridge was number 7, the bit about the vacuum, while not entirely wrong, was 8.

After an hour, things weren’t getting better, and I was going to risk it.  I wasn’t going to spend all night in the car.  Press on, like I’ve been trained.  So I did.  I was a little more than halfway home, and made it without further incident.

I found out this morning not only is what I did a bad idea, it may well be the worst.  Well, OK, not worst- standing atop the bridge holding a metal golf club aloft after attaching my entire zipper collection to my metal suit while soaking in a vat of lighter fluid and smoking crystal meth would be worse, but a car is a deathtrap in a tornado, and the overpass only makes it worse.  As far as tornado safety goes though, es no bueno.  The Storm Prediction Center of Oklahoma has posted a detailed and fairly complicated analysis of “Tornado Vs Overpass” behavior here, but I’ll simplify it (it’s about 25 pages long, so what follows really is a simplification).

As I mentioned earlier, the instinctive thought is “tornados suck you up”.  This is true- except that it does not only do that.  The funnel cloud, if one is even present, represents the center of a vortex, a low-pressure area, which is causing wind to swirl around it.  The general direction is up, but there is a huge sideways component that can extend “a considerable distance” (when they talk about half mile wide tornados, for instance) from the visible tornado!  The winds may be at their fastest at the edges, in fact.  Think about swinging a rope around in a circle- the tip is moving much faster than the base where you’re holding it.  This isn’t exactly the same of course, as there is no solid lever involved, but the principle is similar.

Second, the debris from a tornado (one might argue the most dangerous component) is likely to get snagged by the bridge, dumping cars or trees or pieces of buildings or rabid prairie dogs on you.

Most overpasses don’t have anything to hang onto if you are getting pulled by the wind, and the one I was under was no exception.

The best response in my case was to stay away from the tornado, of course- I should have driven at right angles away from the thunderstorm.  In my case, that would have meant turning around, and probably sleeping in my car, or a hotel room, in Lawton that night, but it would have been the safest course of action.  Since I insisted in driving into the storm, the next best course of action would have been, assuming I saw a tornado, to stop the car, get out, and run for a ditch somewhere a good distance from my car, and lie face down protecting my head until the tornado passed.  The reason this (very counter-intuitive) option is safer is because tornados lose wind speed as they get closer to the ground- and at the ground level, the wind speeds are zero.  The further you get from the ground, though, the faster the relative speed rises.  This is the reason to stay out of the car- they’re high enough to guarantee they’ll be hit with very high wind speeds, making you even more likely to suffer injury by getting rolled over (by which I mean tumbled like a child’s toy, possibly being picked completely up and slammed into something), showered by broken glass or trapped inside.   Lying face-down in a ditch is safer because debris is less likely to get dropped on you and you aren’t likely to get blown around, but is still a “last ditch stand” that should be your final, desperate option.

I made it home safe, largely because the storm didn’t generate a tornado at that time (as I said, it had earlier, almost at that very spot), but I did make a couple of decent decisions along the way.  Pushing through the storm slowly, until visibility improved, and increasing my speed to something high but safe (the speed limit) until I’d gotten out from under the storm.

Tornados are one of those instances where your “gut” will lead you wrong, and the only remedy is research- at least enough to understand your risks.  I have now (not too late, luckily), and hopefully this helps you if your ever find yourself in one of these situations.