June 5, 2008

Statistics:

Initial Target: Great Bend, KS
Departure: Belleville, KS 10:30 am
Arrival: Unionville, MO 1:00 am
Intercepts: Lyons Co., KS
Tornadoes: 0
Hail: Non-Severe (not measured)
Wind: Non-Severe (not measured)
Features: Shelf Cloud
Miles: 616

Summary:

High risk setup and second of two days plains trip.  Targeted Great Bend, KS along dryline where strong instability was forecast to meet high helicity by early evening.  Departed Belleville, KS late morning with initiation already underway in southern KS.  Storms quickly formed a line a along the dryline with some embedded supercells.  Noted a few bases as we dropped to various cells south of Salina, but mostly low contrast linear structure.  Finally intercepted discrete tornado warned supercell north of Hutchinson, KS, but contrast was too low and extreme storm speeds prevented us from following storm.  Stopped for dinner in McPherson and dropped further south to be overtaken by the line before punching out ahead again near Emporia on our way back home.  Noted small storm with rotation ahead of the line near St. Joseph, MO but it was quickly overtaken by line.  Stopped in Unionville, MO for the night.

Crew and Equipment:

Chase team included Chad Cowan and Ben Leitschuh.  Equipment: TH-F6A Tribander, and GPS/Cell Phone equipped laptop.  Photography by Skip Talbot.

Details:

Friday was supposed to be the main show in our two day trip to the Great Plains.  A screaming 500mb jet over a tight dryline with strong instability laid the ingredients down for a widespread severe weather outbreak.  The veering between the 850mb and 500mb levels was not great, however, and there was some question about if we would wind up with supercells or a big squall line.  Up in Nebraska where a very deep surface low was tracking, surface winds were forecasted to back more to the southeast providing better low level directional shear, but with less instability.
We got up late and headed down to Concordia for some breakfast, stopping at Kristy's diner, which featured an amusement assortment of signs on the front:
The Optimist Club bench was our good luck charm for this chase, and we made Chad sit in it.

After breakfast we debated whether to target Kansas or Nebraska.  We settled on the Kansas target as the helicity was forecast to increase later as the low level jet strengthened.  As we started south toward Salina, we passed Andrew Pritchard heading north making for the Nebraska target.  Who would pick the right target?  In the end... none of us.

The dryline lit up much earlier than we hoped for, and filled in to the north looking way too linear.  Also, with strong jet stream overhead, storm speeds were ridiculously fast, approaching 60 mph.  The plan was to intercept the line and drop down from cell to cell or let them pass us.  There was no way we could keep up with them.  Some mammatus as we approaching the north end of the line near Lincoln, KS:
We stopped for some pictures near Vesper, KS, letting the line come to us.  Our view of the base was shrouded by precipitation so instead I shot a picture of this cow, and some convection going on the dryline to our west:
The College of DuPage team showed up a few minutes later and setup on the road north of us.
We all agreed that our viewing from this position was not the best, so we went back east a bit and dropped south.  Looking east away from the storm with the anvil stretching overhead and mammatus underneath:
Looking west at billowing convection above the storm's updraft base as it went screaming by us to the north. 
A storm went tornado warned two counties to our south.  I wondered out loud if COD would haul down to that storm, and sure enough, we saw them fly past us two minutes later.  Some unidentifiable lowerings under the storm's base:
We eventually let our storm go and dropped down south to the tornado warned storm as well.  Visibility was not the best and we saw a ragged shelf like lowering ahead of a massive precipitation core:
Finally, a discrete storm went up ahead of the line well to our south.  Intercepting did not take long due to the storm motions, but we had to dodge a few severe cores on the way down.  The storm was exhibiting high precipitation qualities and we were unable to discern a good rain free base.  Looking southwest at the most discrete, tornado warned storm we saw that day:
We  were able to keep up with the storm for a short ways, while we had a road that paralleled it to the north before we had to turn east to avoid getting cored.  Some ragged lowerings under a very rainy base:
We lost the storm and stopped in McPherson for some grub, hoping to play Tail-End-Charlie of the line after dinner.  The line, however, extended all the way down to Texas and was one gigantic linear mess by that point.  We continued south however to mess around with a severe warned bow echo.  Chad got us worked up for a moment when he spotted this feature, but it was just scud condensing under a disorganized looking shelf cloud.
After letting the line hit us, and experiencing less than severe winds, we started heading east for home.  We finally broke out ahead of the line near Emporia, and had to turn off onto highway 136 in northern MO to keep ahead of it.  Along the way we followed a discrete storm ahead of the line that had a nice RFB and was exhibiting some rotation on the radar, but it eventually got gobbled up by the line north of St. Joseph.  We stopped in the small town of Unionville, MO where a woman in a nightrobe and slippers gave us a very large motel room at a very reasonable price.
Conclusion:

This was supposed to be the main event of our trip, and a big high risk outbreak.  Instead we wound up with a gigantic squall line bust.  The Nebraska target didn't really fair any better with rather weak, scattered storm development.

 

Lessons Learned:

  • Extreme shear and instability make for a light speed, linear bust if there is no directional shear.