May 5, 2007

Statistics:

Initial Target: Hays, KS
Departure: Smith Center, KS 11:30 am
Arrival: Goddard, KS 1:00 am
Intercepts: Great Bend, KS
Tornadoes: 1
Hail: Non-Severe (pea sized)
Wind: Non-Severe (not measured)
Features: Tornado, Wall Clouds
Miles: 586

Summary:

High risk setup in KS.  Chad Cowan and I departed from Smith Center, KS where we had spent the night to intercept a morning storm moving north into NE along the dryline.  Were unable to catch the fast mover so dropped south to a line of severe warned cells noting elevated based, and finally a wall cloud on one of the southern cells near Great Bend.  Retreated north and west, ahead of the dryline in Hays to be downstream for reinitiation.  Looped back south to catch tor warned supercell southwest of Great Bend.  Intercepted large wall cloud and tornado as the storm gusted out, but pursued it north of Great Bend.  Turned south to intercept nocturnal, tor warned supercells but did not witness any structure and stumbled upon damage from May 4.

Crew and Equipment:

Chase team included Chad Cowan.  Equipment consisted of a TH-F6A Tribander, and GPS/Cell Phone equipped laptop.  Photography and video by Skip Talbot.

Video:

Great Bend Wall Cloud and Tornado (3.3MB WMV)

Details:

The second setup in a two day chase marathon to Kansas, Chad and I awoke in Smith Center to a high risk with a 30% tornado forecast and a PDS red box issued from 10am to 10pm.  SPC described strong instability already present and little cap. A cell was going up west of us near Norton, moving north-northeast and we decided to go after it.
We blasted west from Smith Center to Norton after the lone cell, hoping to catch it before it passed Norton.  It became clear though it was moving too fast and that we'd have to fall in behind it, playing catch up, and wouldn't intercept it until it was in Nebraska.  That and the fact that it appeared to be dieing in the capped/lower instability of Nebraska led us to call off the pursuit.  We stopped in Norton for food and gas and met up with a chase tour group.  More cells were firing to the south so we hastened our departure.
Dropping south of Norton we intercepted a poorly organized, sub severe cell just before 1 pm.  We paused for a few pictures and chatted with a local before departing for some severe warned cells to our south.  Looking southwest at the updraft tower:
We made for Hays to intercept the southern end of a line of linear, yet severe warned storms.  En route we saw a new line fire to the east near Russel.  On the way to Tail-End-Charlie a snapped a photo of this slightly elevated, featureless base.
A decent looking cell in a line of messy convection finally presented itself and we intercepted it near Olmitz at 3:30 pm.  A wall cloud was evident under the storm as the base came into view.
We got right up under the base of the storm.  The wall cloud retreated and a good deal of rain was coming out of the base.  The storm was lacking, but Chad and I were enthusiastic about having intercepted a base and were hoping it would further organize as we watched.
We bumped into Tony Laubach on a gravel road north of Otis.  After liberally expressing his discontent with the storm, we parted ways.  Tony went south to the dryline, and we followed the storm a bit longer before heading north through Russel and then Hays.  The thinking was that we'd be sufficiently downstream to catch anything that fired on the dryline.  We were a bit too far downstream, however, as a nice supercell went up right where Tony headed, and we had to haul butt back down south to intercept.  We drove on some of the same roads we had been on earlier, make a big loop.
After relentless speeding south past the west side of Great Bend we caught sight of the supercell.  We approached it from the north, trying to pass its east side before it crossed our path.  The precip core flanked us slightly but we made it to the RFB without getting cored.
A big ragged wall cloud came into view.  It was an order of magnitude larger than the one we had seen on the earlier storm.  This was a real beast of a supercell.
"Let's get close!" I told Chad and we drove up about a mile short of the wall cloud, anticipating it to move northeast past us.  We set up for video and stills, noting that a new, yet rain shrouded wall cloud was forming inside the precip core.
Contrast wasn't the best and the base of the storm was rather grungy, but it still exhibited dramatic features.
The wall cloud appeared to be bowing out like a shelf cloud and there was no discernable rotation underneath it.  There was lots of scud moving around however, and occasionally a rain shaft or RFD dust plume would kick up under it, grabbing our attention momentarily as we thought it might be tornadic.
The wall cloud was not moving northeast as I had originally guess but, had a much more eastward component to its motion.  The wall cloud was coming straight for us.  "We don't want that to go overhead!" I exclaimed to Chad.
A dramatic, but blurry shot of the tail of the wall cloud.  We were slow to move and the wall cloud went straight overhead.  There was no rotation above us like on April 24, however.

We got rolling east to keep ahead of the storm, turning north briefly but coming back to highway 19 after our north option turned out unacceptable.

The wall cloud was continuing to bow out and the base of the storm was taking on a whale's mouth type appearance.  "Its gusting out," I said to Chad, "Let's plot a south route and drop down to another storm."  As Chad analyzed the route I saw a chaser ahead of me run off the road.  It was so abrupt and he went so far into the ditch that I thought he had lost control of the vehicle.  However, the chaser immediately jumped out, camera in hand.  Something was up.  I tried to look left while driving and caught a glimpse of something white hanging under the base.  "Chad... is that a tornado?"  Chad took a quick glance, "I don't think that's connected."  I looked again, "Chad, that's a tornado."  "Its a tornado!" he agreed.  I too abruptly pulled off the road and we jumped out for stills and video.
Great Bend Wall Cloud and Tornado (3.3MB WMV)
Chasers came out of the woodwork.  The rural roads were alive with dozens of vehicles, geeked out with antennas and instruments.  I told Chad to get a few pictures, and that we need to keep moving.  The tornado was poorly contrasted and I wanted to get ahead of it, and closer as it was too obscured by the precip core.  We headed east with the tornado still on the ground, passing a multitude of chaser.  We passed Mark Sefried and Darin Kaiser, Drarin frantically waving thinking we were oblivious to the tornado.  We turned north near Seward, and got stuck on a gravel road behind a pickup truck with blinding strobe lights on top.  The road was not fast enough to pursue the road and we were stuck for miles before we finally got back to 281.  When we finally made the turn I took a look behind and noted about 20 chase vehciles had filed in behind us on this little gravel road.  It was unreal.  We turned north to keep up the storm, the TIV passing us going south, which almost made me rethink our route.  Looking north at what appears to be an RFD clear slot:
After seeing a tornado drop in what appeared to be a dieing storm, we didn't know when to abandon this storm.  It was still showing good low level rotation on the radar so we kept up with it.
We followed the storm northeast of Great Bend, stopping at an observation area in a wetland.  There was a good deal of scud motion but the storm was appearing ever more outflow dominant.
The following two stills are from Chad's camera.  After a heavy contrast enhancement, it appears that there was a very low feature, close to the ground, possibly a large tornado.
The contrast enhancement:  Looking north about 8 miles northeast of Great Bend at approximately 7:30 pm.  Other chasers noted a similar type feature, also believed to be a tornado, but earlier and south of Great Bend.
A huge parade of chasers:
Chad and I dropped south on the line for some nocturnal chasing.  North of St. John we got on a messy, tor warned cell.  We got within about two miles of the couplet, stopping on a gravel road, now alone from the chase horde.  There was a large precip core that was the southern porition of the hook preventing us from seeing anything under the base.  Lightning illumination was not helping either.  As we watched this storm I started to hear a rumbling in the distance.  It got louder and I thought to myself, "That sure sounds a lot like a train... uh oh."  Chad heard it too and we both listened carefully as it grew louder and louder.  Chad asked, "Have you ever heard a tornado before?"  "No" I replied.  I spotted tracks immediately ahead of us, "It has to be a train, look at the tracks right there."  But the crossing lights never came down and there was no train in site in either direction.  Then the air raid sirens started to sound.  Chad and I finally put two and two together: there was a shed in the distance with a big diesel generator that was powering the sirens.  The tornado like rumbling sure got our hearts going though!

We dropped south again onto yet another tornado warned storm.  Lightning illumination was not as good as it was the previous night.  Along the way we noticed downed power lines, and then some snapped in half.  We proceeded very slowly, not wanting to hit debris that might be in the road.  The trees were stripped and we spotted a tractor wrapped around a trunk.  At first we thought it was caused from the circulation we were chasing but realized that roads were clear.  This was from a tornado the previous night.  I checked the map.  We were 20 miles northeast of Greensville.  It could very well have been the same EF5.

We let the storm go after encountering the debris and decided to call it a night.  We stopped for food in Pratt at a place a local recommended: "Chapaeu."  It was a little pub type joint that also served food.  Chad and I had a round of beers and their famous pizza tacos.  It sounds gross, but after 11 hours of no food except some trail mix, they were mighty delicious.

Every room in Pratt was booked from people displaced by the Greensburg tornado and emergency workers coming in.  The next two towns to the east were also booked.  We had to go almost to Wichita to get a room.  Chad and I awoke the next morning to the sirens sounding for a tor warned part of a squall line in the southwestern portion of the county.  We went after it but only encountered an outflow boundary and a precip core that was hiding a weakening area of rotation.  The warning was canceled so we turned tail and headed for home.

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Radar Analysis with GPS Overlay:

KDDC Animated GIF (4.6MB) Individual PNG Frames

 

Conclusion:

This was a fast paced, stressful chase, filled with grungy storms and lines with embedded supercells.  It was rewarding though as we bagged yet another tornado and possibly two if the rain obscured feature we spotted north of Great Bend was indeed a tornado.  This chase had an incredible number of chasers out on the road being a Saturday high risk setup.  There were an incredible number of tornadoes reported this day as well, although the northern portion of the high risk was tornado free.  Storms speeds, lack of visibility after dark, and the road networks also prevented us from intercepting multiple tornadoes like on March 28.

Lessons Learned:

  • With a line of developing supercells, its best to drop down the line rather than trying to follow one storm, and playing catch up with it.