Thursday, 24 May 2012
The drive from Pittsburgh, PA to Wichita, Kansas was long and extremely difficult this time. It had only been about a month since MaryLeigh and I had made the 19 hour drive for the tornadoes back in mid April. But for whatever reason this time the trip was a lot more difficult! We left Pittsburgh at 4:30a.m. Tuesday (May 22) and arrived in Wichita at around midnight (May 23). We were up much later though looking at data and trying to decide on our chase target.
Upon closer inspection later that morning after very little sleep, I decided we needed to drive north to York, Nebraska and wait for storms to form along the cool front. After looking at data in York around 3pm, it was clear storms would form along a pre-frontal trough axis. I knew the tornado potential on this setup was not great, but I was a little more excited seeing that storms would form along anything other than the actual cool front. With the wind shear that would be present, if we could get a discrete storm it would likely be a supercell with at least a shot at producing a tornado.
We headed east to highway 15 and passed through Seward. Storms were intensifying to our north, but as we continued further north the southern most cells weakened and the storms further north began forming into a bow echo. It was becoming clear that the CAP was still too strong. We headed east on higway 92 and things kept looking worse. So, we stopped in Wahoo (interesting town name, huh?) and grabbed a bite to eat around 5:30. I remember thinking that it’s usually not a great sign when you have time on a chase to get something to eat at dinner time!
Finally, a discrete storm developed to our southwest. So we headed back west on highway 92 and dropped south on highway 77. After we passed over a hill we could see a large wall cloud to our southwest! We started getting excited, but the wall cloud quickly became undercut by outflow before we could snap a decent photo in between the trees and hills. But things were looking up, because just 30 minutes ago we were eating fast food and thinking the chase might be over.
We reached highway 66 and pulled over right in front of the mesocycone (it was moving pretty slowly). A new wall cloud was beginning to develop, and before long a nice tail cloud formed. There wasn’t much rotation within the wall cloud, but the storm had pretty good mid level rotation and you could see the rear flank downdraft trying to occlude everything and form a funnel. But the rotation wasn’t strong enough, and cool outlfow pretty much put an end to that. We needed to head east and stay ahead of the storm. I knew a new wall cloud would form soon further east.
Ironically as the wall cloud was falling apart the tornado sirens turned on! We blasted east to get away from the rear flank downdraft rain/hail. The storm remained a supercell and continued producing wall cloud after wall cloud in a cyclic fashion. At one point the storm produced a funnel and MaryLeigh and I both saw a brief circulation in the dirt beneath the funnel. But it was both brief and extremely weak.
So it turned out to be a really fun chase day. We really enjoyed viewing the numerous wall clouds this storm produced, and we were treated with a nice lightning show that night too!
Now it’s time to look at more weather data and decide when and where our next chase target is going to be.
Until next time,