June 14, 2009

Statistics:

Initial Target: Dodge City, KS
Departure: Clarendon, TX 11:00 am
Arrival: Medicine Lodge, KS 9:00 pm
Intercepts: Ulysses, KS
Tornadoes: 1
Hail: Non-Severe (Half inch estimated)
Wind: Severe (60 mph estimated)
Features: Tornado, RFD Clear Slot
Miles: 596

Summary:

Dryline setup in SW KS.  Targeted Dodge City, KS with Adam Lucio.  Departed from Clarendon, TX and headed west from Liberal, KS towards initiation in SE CO.  Intercepted severe warned cell near Johnson City and noted brief lowering.  Followed cell westward into CO before intercepting tail end charlie back in KS.  Followed storm from north to Ulysses, KS noting RFD clear slot and tornado.  Caught in hook afterwards with severe winds.  Broke out ahead to outflow dominant HP supercell.  Called chase off but intercepted again after storm regained tornado warning.  Viewed base from afar noting scud before stopping in Medicine Lodge for night.

Crew and Equipment:

Chase team included Adam Lucio.  Equipment:  Kenwood TH-F6A Tribander, Dell Inspiron Laptop.  Kyocera data card and router, Holux 236 GPS, Robotic camera dome with Sony XR-520V.

Details:

Sunday was the second day in a three day plains run.  We had a dryline setting up on the KS/CO border with a shortwave trough coming in from the west and a surface low over northeast New Mexico.  Adam Lucio and I targeted Dodge City, KS where a dryline bulge was forecasted to kick off storms in the afternoon.
We left from Clarendon, TX where we had spent the night before after Saturday's chase.  We took county highways north through Pampa.  Some undulated showers over the Texas panhandle:
Driving north across the Oklahoma panhandle, the overcast skies gave way and we had our needed sunshine that would destabilize the atmosphere for afternoon thunderstorms.
We crossed into Kansas and stopped in Liberal for a brief data check.  Initiation was already underway in northeast New Mexico and southeast Colorado.  the cap broke sooner than we thought it would so we decided to divert from our original target and headed west towards the developing storms.  We intercepted the southern most cell in a cluster near the town of Johnson City.  West of town we had the base in view with very interesting structure.  It looked it was three tiered with a wall cloud on the bottom.
A few minutes later a rear flanking downdraft punched through the base cutting it into a horseshoe shape.  This often precludes tornadogenesis.  The base of this updraft tower was much smaller than the typical tornadic supercell and it soon fell apart as it was interfered with by a number of other nearby cells.  The main updraft in the complex appeared to be across the border in Colorado, so we ran west after it before we realized it was becoming an elevated hailer and racing off to the north at warp speed.  We turned around and headed back into Kansas after new development to the south, targeting Tail-End-Charlie.
We clipped the core of the storm as we passed through Johnson City, catching some small hail.  Following highway 160 east of town we were able to get out ahead of the storm and get a view of the base.  There were no good paved options further south so we let the east-northeast moving storm come to us.
We stopped just past the town of Ulysses to get some more pictures.  The storm looked like a high precipitation supercell with a lot of rain wrapping around the updraft base.  On the leading edge of the rear flank Adam and I saw some awesome storm structure.  What started as a large chunk of detached scud, rooted itself onto the leading of the base and then started to rapidly rotate.  A dust plume also kicked up underneath, but this was probably just an RFD blast or a gustnade as we didnt see any funnels above it.  Looking southwest:
Looking northwest at the supercell's mean, green precipitation core and Adam using a fence post to steady his camera:
Looking west as a large rear flanking downdraft cuts through the storm's base.  The scale of this RFD clear slot was much larger than our first intercept, and unlike last time, this time a tornado would develop.  You can see the developing tornado in the center of this shot.  We missed the feature ourselves and started to get some rain as the base moved overhead.  Not wanting to get caught in the core of the supercell's hook we decided to keep ahead of the gust front.
I pointed the camera dome to our rear as we moved ahead of the storm just in time to catch the tornado's condensation funnel touching down.  The next series of shots are frame grabs from the video the robotic camera dome captured.
The tornado touches down.  By the time we realized we had a tornado behind us we scrambled to get to an area with better contrast.  We should have turned around, but raced further east to get to a north option so we could get the clear slot behind the tornado.
A classic elephant trunk tornado:
The funnel widens:
The tornado continues to widen.
Before we could get to our north option the funnel begins to break apart.  It barely lasted three minutes.  If we had known the lifespan of this tornado would be that short we would have stopped or turned around for an immediate intercept.  Unusual to many tornadoes, this tornado widened out as it died and then broke apart.  Typically tornadoes rope out, growing skinnier and skinnier until they are as thin as a rope before they break apart.  I hypothesize this tornado lost its rotational energy and just fell apart instead of being stretched vertically into a thinner funnel like most tornadoes.
We got to our north option after the tornado had faded.  We waited a few minutes to see if our supercell would cycle and produce another one, but it didn't.  Meanwhile the storm's heavy core had wrapped around the hook and was now about to swallow us.  We tried to race the core south but it caught us in Sublette and we were hit by severe winds that abruptly changed directions from north to south and back to north again.  It was very unnerving and I feared we were in the process of getting rolled by a rain wrapped tornado.  Looking south just before the core swallows us.
South of Montezuma we were able to get out from underneath the storm.  The sun came out behind us and a low rainbow popped out.  We had now caught a rainbow two days in a row.  Adam and I joked that we should chase rainbows instead of tornadoes since we were better at it.
We were able to get around the bowing out rear flank of the storm and get a look into the notch of the outflow dominant supercell.  There didn't seem to be much happening in the way of tornadoes and if there was it was embedded in the core.  Looking west at a massive precipitation core with shelf cloud above it on the left and the storm's inflow notch and updraft base on the right:
As the storm continued to gust itself out, I prematurely called the chase and we started heading east away from it.  Usually when a storm gust's out its caught in its own cold wake and doesn't produce any more tornadoes.  We had  some scenic views of the storm as we drove away from it:
The storm's gust front over some red clay hills:
Stopping a few miles ahead of the storm for a scenic view:
We headed towards Medicine Lodge to get a room for the night and some dinner.  We were almost there when, to our surprise, the storm regained a tornado warning.  We turned around and headed back to re-intercept it.  Its very hilly just west of Medicine Lodge, so we found a big hill and pulled off into a drive and climbed up a hill to get a view.  We had a great view but couldn't see under the base very well.  The original gust front (foreground) passed overhead and it looked like a second gust front was now bowing out again from the storm.  For the second time it looked like the storm was done. 
After watching a lot of scud moving around the base, and talking to a tipsy, local spotter who spotted us on top of the hill, we called it a night and headed into Medicine Lodge.  We got a room at the Budget Inn but were stuck in the back building.  The building looked quite creepy, alone and unlit, but it was in decent shape and had fast wifi so I wasn't complaining.  Luckily there was also a diner at the gas station right next door that was still open so we were able to get dinner as well.
Conclusion:

Adam and I scored a nice elephant trunk tornado on this chase.  It was a bittersweet victory though as we were not in a prime position to view it, and if it weren't for the camera dome, we would have missed it completely.  This tornado was the only real catch of the day in southwest Kansas as well.  In other areas,. there was some upslope play in eastern Colorado with tornadic supercells as well as supercells in the Texas panhandle.

 

Lessons Learned:

  • In the head of the moment do a "stupid check" and look around to make sure you aren't missing anything.
  • Move on a tornado intercept, don't bet that its going to stick around for a more ideal viewing position.