I had been watching this system for several days thinking there could be a potential for low-topped supercells such as typically occur with cold-core setups, to the north of the main warm sector. The following posts I made on Stormtrack illustrate my ever-changing thinking on this system:
04-12-2009, 02:36 PM
Surprised there is no thread yet for Monday. There are two areas of possible play, along the Gulf Coast and in the Ohio Valley. Since the latter is within my chase range, I will focus on it. It is looking like a decent cold-core setup may develop in southern IL and IN and western TN and KY; and possibly extreme southeast MO. I'm not sure there is really going to be enough moisture and instability, but in these cold-core setups you don't need as much, and the shear certainly will be there. Right now I am liking the Evansville, IN area or just north, fairly close to the triple point. There is also potential south and southwest of there, but I'm a little nervous about getting stuck somewhere near initiation where you can't cross the Mississippi or Ohio River and thus would lose the storms almost as soon as you start. And perhaps being near the warm front will add a little extra spin to any storms that develop in SE IL or southern IN, so tentatively that is what I am considering, depending of course on how things are looking tomorrow morning.
04-12-2009, 09:48 PM
On this evening's NAM, I see nothing to encourage me about the Ohio valley target area that looked earlier like it had some potential for tomorrow. The instability and moisture are even worse than earlier, and the upper support is more out of phase with the surface dynamics than was the case earlier. It might be better farther south where the moisture and instability may be better, but if I don't see something in the morning to change my thinking, I may sit this one out. I suppose the evening GFS could show me something more encouraging when it becomes available, but I didn't see anything in the 18Z run to get me excited. Best dynamics looked to be a little farther northeast, along the warm front from around Terre Haute to Indianapolis, but again, pretty anemic.
4-13-2009, 11:08 AM
I am heading for Evansville, IN. This morning's runs look a little better on warming and moisture return, and I am thinking there may be an OK cold-core play in the I-64 corridor between Evansville and Louisville. There should be enough directional shear to make it interesting if strong storms can get going. It's marginal, but I am itching for the season's first chase, and you never know what might happen with these cold-core setups.
As it turns out, I should have already been on the road when I made the above post. I was perhaps swayed a bit too much by the NAM model and the SPC outlook, which both had the storms firing near the IL-IN border and moving northeast. I should have paid more attention to the RUC, which was showing the action farther east, and I also should have started earlier. The result for me was a 600 mile bust in southern Indiana. As I said, I had the right general idea, but the storms initiated 100 miles or so east of where I thought they might - and as a result I was never quite able to catch up. I was still well to their west when the storms initiated west and northwest of Louisville. Visually and on radar the storms northwest of Louisville looked good, and there were several TOR warnings northwest of Louisville and south of Indianapolis. But, being behind the game as I was, the closest I ever got to any decent storm was 10 miles or so to the southwest as it raced away from me. By the time I headed north on I-65 toward IND, the show was over. There was one report of a funnel cloud about midway between Louisville and Indianapolis, but that was before I made it to that area. Several reports of up to golfball hail, too. I could see some decent structure including what looked like a couple distant wall clouds well off to my north from I-64 between Corydon and Louisville, but never could get close. Never had time for pictures playing catch-up as I was.
There were no tornadoes in the LMK or IND CWAs, though quite a few hail reports, so I guess I did not miss all that much, but would liked to have had a better look at the storms. Here are the local storm reports:
LSRs from Louisville NWS
LSRs from Indianapolis NWS
At least my equipment worked well, except that I need to get a cigarette-lighter power connection for the laptop so the battery doesn't run down.
Total chase distance: 602 miles.
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