STATUS: 4 Apr 2017

I’m still in Huntsville.  My one attempt at getting back to my desk, and my boxer, failed when I flew to OKC (two attempts), and had to drive straight back to Huntsville.

One of the more interesting things I have observed here involves all the misperceptions about VORTEX-SE objectives and decision making.  VORTEX-SE is not all about catching significant tornadoes when the risk is well recognized.  It is much more about tackling all the crazy uncertainties that arise whenever tornado potential exists.  Those readers who understand probability know that tornado potential is very close to zero most days of the year… so close that a forecaster could say “there will not be tornadoes”.  But the biggest forecast problems are when the probabilities are, say, in the few-percent range.  So, in VORTEX-SE we lean heavily toward operating in iffy situations because there is so much to learn, even if no tornado occurs.  When VORTEX-SE operates, it’s not because we are saying “there will be tornadoes”, and disagreeing with NWS and SPC forecasts.  We are operating because we are saying “there is a large enough chance of a tornado that we need to study the way the atmosphere is behaving.”

We don’t define success as the number of tornado deployments vs. the number of null deployments. We define success based on the amount of new knowledge we can generate that improves our understanding of tornado environments, and the predictions of the weather associated with those environments.  No doubt the mood of the researchers sours a lot in these null cases, but by and large we know that we have to be here observing the null cases to have any hope of observing the tornado cases.

Back to the weather.  We deployed yesterday in western AL and watched some micro-supercells move toward the network from MS.  I will probably be skewered in (Anti)Social Media for calling them that, but these cells were persistent, had low-level rotation, and even modest lowerings.  They were only about 15000 feet tall, and didn’t make any cloud-to-ground lightning.  So, scientifically fascinating, but not much of a threat.

Now we turn our attention to tomorrow.  In general, our numerical forecasts suggest a large enough risk for tornadoes in our domain that we must operate.  That’s about the best we can usually say 1-4 days in advance.  VORTEX 94-95, VORTEX-2, and VORTEX-SE have shown us that there are a lot of ways for the atmosphere to bust a tornado forecast, and only a slim chance that all ingredients will really fall into place.  But we will be deployed, and we will be doing everything we can to learn more about the factors that raise or lower tornado potential in otherwise favorable-looking scenarios.



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