19 April 2011
The Storm Prediction Center in Norman (They are the ones who issue the tornado and severe thunderstorm watches) has indicated a moderate risk of severe storms on Wednesday afternoon and Evening over much of the Midwest. After last weekends swarm of tornadoes, this is not good news, but it is April and some of our deadliest tornado outbreaks have been in this month. There are already signs in the numerical model runs that are setting off alarm bells in my mind tonight.
If you draw a line through the axis of the upper level trough, you see that it is slanted backwards. Meteorologists call this a negative tilt trough and it tends to give you a wind shear pattern favorable for strong tornadoes. A strong low level jet (about 3 km above the ground) looks to be present as well, and this will transport in a lot of warm and moisture laden air from the Gulf, to add to the mix.
Missouri,Illinois and Indiana are the most likely locations for strong tornadoes Wednesday. It sounds terrible to say, but when I see these kind of ingredients, I know there are people in that moderate risk area who will be killed by a tornado tomorrow. They are most probably living in a mobile home, and when the tornado warning goes out, they will be thinking the odds are in their favor.
They are actually, but someone has to get the short end of the stick. If you are in a mobile home, have a sturdy structure to go to as the storms pass. We had 7 deaths in Alabama last Friday and all of them were in mobile homes. The lesson here is that you can survive a strong tornado, but not in a trailer.