2 April 2012

Severe Weather Warnings Will Soon Come in Several Flavors

Posted by Dan Satterfield


Doppler radar image showing winds over 60 mph approaching the Eastern Shore of Maryland. Warnings for this type pf storm should carry more weight than a warning for quarter size hail. They soon will.

The NWS is testing a new type of tornado warnings beginning this month in Missouri and Kansas. Trust me, this is a good idea, I suspect this will go nation-wide within a year or two. When it does it will make many of us who are the ones who interrupt your favourite TV programs happy.

The problem now is that all tornado warnings are not created equal. When it comes to severe weather, it is better to err on the side of caution, and when there is a moderate rotation in a super-cell (with no spotters nearby to confirm whether or not a tornado is developing), then it’s a tough call for an NWS forecaster to push the button and warn on it. Many stations will interrupt programming for the entire length of the warning, and frankly this is not always needed.

I myself (in the past) have been in the situation of interrupting a popular program when I know that the storm is not at all likely to produce a tornado. When I say the risk is very low, then people would get irate that I was staying on air, and who could blame them. Many stations give the meteorologist little or no say on continuing the coverage, and It’s hard to tell viewers that I had to cover over their program when the risk really did not justify it. On air text banners and occasional interruptions can be tailored so that viewers see their program, but still see that there is a warning.

There is another side as well. In some cities, especially larger ones, wall to wall non-stop coverage is rare, and the meteorologist needs to have a good reason to break into programming on an ongoing basis. It’s a tough call for management and the meteorologist. I’ve seen super cells that were so severe that it was a good idea to go on and stay on for a while to track the storm, and tornado warnings that could best be covered by a few short interruptions. NWS forecasts will have two levels of severe thunderstorm warnings under this new policy and it too is needed.

Doppler radar indicated tornadoes will be one class of warning with another class being reserved for storms that look very intense with extreme rotation. A third category, the most dangerous category, a “Tornado Emergency” will be reserved for confirmed tornadoes on the ground. Tornadoes like we saw in Alabama on March 2, and on April 27, 2011 would obviously fall into the latter category. “Tornado Emergency” has actually been an option for a while but rarely used. After the tornadoes of the last 15 months, it’s high time to change things and kudos to NOAA for taking the steps to do just that.

You can read more about the new warnings being tested below: