May 22, 2011

Statistics:

Initial Target: Lancaster, MO
Departure: St. Joseph, MO 8:00 am CDT
Arrival: Westchester, IL 11:30 am CDT May 23
Intercepts: Slater, MO
Tornadoes: 1
Hail: None
Wind: Non-Severe (not measured)
Features: Tornado, Wall Cloud, Mammatus
Miles: 797

Summary:

Second day in a two day plains run, starting from St. Joseph, MO. Targeted southeast IA for supercells initiating ahead of a cold front by early afternoon. Stopped in Lancaster, MO to await initiation. Storms fired well north and south of position. Targeted storms downstream in west central MO. Intercepted tornado warned cell near Slater, MO noting lowering that quickly organized into well defined wall cloud. Pursued storm as rope tornado developed, following from the south until tornado roped out near Glasgow, MO. Fell behind storm at Missouri river and followed from behind before calling it a chase and stopping for dinner on Moberly, MO. Gorgeous mammatus display before stopping for the night in Jacksonville and heading home in the morning.

Crew and Equipment:

Chase partners: Jennifer Brindley.  Equipment:  Kenwood TH-F6A Tribander, Dell Inspiron Laptop.  Millenicom 760 USB datacard and cradlepoint router, Holux 236 GPS, Robotic camera dome with Sony XR-520V. Canon 60D and EF-S 10-22mm

Photography courtesy: Jennifer Brindley

Video:

Details:

Sunday, May 22, found Jennifer Brindley and I on our second day of a plains chase trip. After scoring a tornado the day before, this chase was just going to be icing on the cake, with any catch being a bonus. With the moisture axis pushing east into Wisconsin and extending through Missouri into Texas, a cold front was to be the focus for storm initiation.

Cold fronts are often not the most favorable boundaries to play as the strong linear forcing often kicks up a squall line or the storms get undercut by the cold air. Winds were better backed up to the north in Wisconsin and Iowa, but instability was significantly better in southwest Missouri down into Texas. I had to be back to work on Monday, so we picked a target that compromised between the better shear and instability and was on the way home as well: southeast Iowa.

We departed from the north side of St. Joseph a little after eight in the morning and were barreling across the top of Missouri on some back county roads, snaking our way up to 136. The steep hills sent both of our stomachs tumbling. We stopped for breakfast/lunch at the Toot Toot restaurant in Bethany, MO before shooting across the top of Missouri on 136. A robust cumulus field had developed by early afternoon and I decided to stop us just short of our target, a few miles south of the Iowa border at a gas station outside the town of Lancaster, MO where we had a view of the west sky.

We spent almost an hour parked at the gas station awaiting initiation. A local in a pickup came by to see what we were up to and informed us that storms never hit the Lancaster area. They always split to the west and go north and south of town. I was amused by the local myth that seemingly exists everywhere, so I just smiled and nodded, while Brindley snagged one of her famous "locals portraits":

 

As if to validate the local legend, storms did indeed fire north and south of where we were sitting, initiating a good 50 miles to our north and moving away from us, and even further away to our southwest over western Missouri but moving a little bit more in our direction. We were stuck now between the two clusters and had to make a decision on where to go. Terrain would be better to the north as we got into Iowa, but we would be playing catch up trying to reach storms moving away from us. The instability was better to our south and there was actually quite a bit of helicity being plotted ahead of the cold front storms, plus storms were heading in our a direction. We started heading south down highway 63 out of Lancaster making for developing cells.

A line of returns was showing up on the radar to our south and and just north of Lancaster, and I was worried whether or not we were going to make the right decision. We started heading down the line of cells but they were dying as quickly as they were forming. Reviewing the situation afterwards it appears that there was some dry air intruding in the midlevels, causing the storms to evaporate. We continued on hopping down the line targeting cells further to our southwest.

A couple of cells moving east out of Kansas City went tornado warned. We were still more than an hour out from an intercept, but Brindley and I decided to go after them. We turned west on US 24 out of Moberly for the intercept. A couple tornado reports came in on our storm and I feared we were going to be too late. Meanwhile the terrain was degrading as we headed deeper into Missouri. The roads were twisting and became more hilly. It took seemingly forever to reach the storms. Even though they were moving toward us, the storms seemed like they were perpetually 30 miles away. The lead cell maintained its tornado warning, however, and we finally started to get a low contrast view of it as we approached Slater. There were cells encroaching on it from the south, but I figured we'd shoot for the inflow notch anyway, before everything completely congealed. Heading west out of Slater was our one shot at a view at the base, but we had to take gravel roads south to get on the next storm in the line. Through the rain curtains we had a low contrast view of a base before it completely filled and I turned us south trying to race some severe warned cells that were heading east.

I took the road as fast as the loose gravel and ruts would allow. Low hanging scud from the forward flanking gust front started to pass over the top of the van, making Brindley and I uneasy after our close encounter with the tornado the day before. We got clipped by the core of the storm briefly, but managed to make it out a few minutes later and back onto a paved highway heading east. We got out in front of the storm's gust front and found a turnout off the side of the road to stop and watch the storm.

A ragged base, or a weak attempt at a funnel as we pulled ahead of the storm's gust front:

A pickup truck with a couple of local spotters pulled in to chat with us, asking us if we had seen anything. I told the spotters that the storm wasn't really impressing me much, with a shelfy, mostly linear appearance. There was a more discrete looking cell to our southwest and I told them we were going after that instead. Meanwhile a couple of other chasers had spotted us parked off the side of the road. Not wanting to get stuck in the convergence, we we escaped back onto the highway.
Our road headed conveniently southeast down to and ahead of the next storm. As we left our original storm, however, the northern end of the shelf cloud expanded into what was looking more and more like a classic wall cloud. We stopped briefly to watch the storm. A tail cloud started to form, extending off the north end of the wall cloud. We weren't leaving this storm.
We cut across the top of Marshall, MO before hitting a north highway to get back up to the base of the storm. The storm fanned out in front of us and we took the next east option we had, not wanting to find ourselves under a wall cloud, racing a tornado like we were the day before.
Looking north at the low hanging wall cloud, surging out ahead of the rear flanking core:
An inflow tail starts to form on the nose of the bowing wall cloud:
Heading east on a deserted county road, we were able to get ahead of the storm but I could no longer watch the base closely as it was over my left shoulder. Brindley spied something pointy dangling under the base, but knowing my adamant attitudes towards not calling out scud as funnels, and the sharp criticism I always I give to the over eager spotters that call in false funnel reports, she didn't say anything right away. "Is that a..." I looked over my shoulder and saw a cone funnel hanging about a third of the way down from the base and quickly lowering.
Brindley got a few stills through the sliding door window, while I looked for a spot to pull off. The funnel briefly condensed down to the ground. We had a tornado for two chases in a row now. We pulled off to the side of the road and got out, Brindley shooting the tornado while I attempted to fix some glitches in the dome camera. The tornado became a truncated tube.
For once, we were in a nice, safe spot to watch the tornado, south of its east moving path. Unfortunately the rain free base was not rain free to the south of the tornado, and a high precipitation rear flanking core was moving in our position rapidly. We couldn't linger too long before the precipitation core hit and we had to start moving east again to keep our view.
I sped down the road as it transitioned to gravel, trying to get out ahead of the rain, while watching the tornado off to my left, completely overlooking the tee intersection ahead. Brindley called out a warning and I thought for sure we were going off the road, but a combination of braking and spinning the wheel, and we made the hard left turn at about 20 mph.
Video capture from the dome showing the tornado, wrapped in curtains of rain, with a partially condensed funnel and debris cloud:
We went north a quarter mile heading a little ways closer toward the rope tornado before our road went east again. With the rain right behind us, instead of continuously playing leapfrog on the storm, stopping and going, I opted to get well ahead of the storm into a position where we could shoot the tornado at a close yet safe range, and in clear air. We made for a bend where the road turned north at the Missouri river. The plan was to get as close as safety would permit as the tornado crossed the road in front of us, getting a dramatic shot of a rope at close range.
The tornado seemed to peak, kicking up a large debris cloud:
In hindsight this would have been the time to stop and shoot the tornado, as it would soon start to rope out, but we still wanted to get the best possible shot so we kept going.
Brindley still managed to get a few great stills out the driver side window, while the camera dome video was hopelessly smeared with raindrops.
The funnel retreated, leaving behind a twisting plume of condensation and debris:
 
The road took an odd little U shaped jog around a tree lined hill and we briefly lost sight of the tornado. When we emerged on the other side, the tornado had stretched into a tall, super skinny rope with the green core of the storm behind it.
Our road turned north and we were in position to get dramatic up close shots of the tornado. The weather never plays out exactly how you want it too, however. The tornado roped out and dissipated just before we made it our intercept point.
We stopped on the side of the road anyway to let the tornado producing region of the storm pass, as we watched the last bit of swirling rotation under the updraft base before it crossed the Missouri River.
 
 

Gorgeous structure on the back side of the wall cloud, lit up white from light filtering through the rear flanking downdraft clear slot. Looking east:

 

As the road turned north and we had to pass through the town of Glasgow, we fell behind the storm. We made a vain attempt to catch back up with it but the twisting Missouri highways east of Glasgow were not very fast roads, and we'd have to punch the storm from behind to get back into a viewing position, which Brindley and I agreed wasn't worth it. We already got our tornado and didn't need to push our luck. We started to get into the precipitation core of the storm where highways 3 and 5 forked, so we pulled off to the side to let the storm pass a bit before we continued on. A couple of other local area storms chasers pulled in behind us and we chatted for a bit about the tornado earlier and how best to stay with the storm.

We made a vain attempt to keep up with the storm taking winding roads through the hills and trees. Brindley wanted to get a dramatic shots of a tornado, framed by a gap in the trees and hills with the road stretching out ahead. All we managed to see were a few glimpses of the base, however.

Looking east at the curling northern flank of the wall cloud (left and center) cut by the rear flanking downdraft (right):

Coming into the town of Higbee we decided to call it a chase as we were hopelessly behind the storms, which were turning more and more into a linear complex by this time anyway. We headed up to Moberly to grab some dinner at the Golden Corral. The anvil from our storm stretched over half of the sky, while the stable air behind the line of storms made for clear blue skies across the other half. Mammatus were starting to peak through on the bottom of the anvil, and we snagged a few pictures before heading in for dinner.
 
It was after dinner, however, when we were treated to a spectacular sunset mammatus show. We headed northeast making for home on 24 behind the line of storms. The sun dropped below the anvils and lit the mammatus up in fiery orange shades. The sunset colors and clouds were the most photogenic part of our entire day. Brindley snapped off dozens of stills before the sun dropped below the horizon and we lost our good light.
 
 
 
 
 
 

 

I was incredibly beat from our two days of marathon driving across the plains and exciting tornado intercepts. We were still in Missouri after 9pm and I knew I'd be too tired to finish the drive that night so we stopped for the night in Jacksonville, IL, finishing the few hours drive home in the morning.
Conclusion:

Two days in a row with photogenic tornado intercepts is a pretty rare treat for my chase record, with it having happened only twice before. We kept our distance from the tornado, and stayed in a safe position relative to the storm, after learning our lesson the hard way the day before. We didn't get our coveted close up rope shots as the tornado roped out before we could make it to our intercept spot, but the chase was still a stunning success with Brindley capturing plenty of great stills of the tornado and storm structure, and me being able to salvage some of the video from the camera dome between gremlins in the electronics and raindrops on the dome. Tragically, this was also the day of the Joplin EF5. We didn't hear about the tornado until we stopped for dinner, when it was on the news, and even then we didn't realize how bad the devastation actually was until the following days. The Joplin tornado was the deadliest in decades, killing over 100 people. I thought death tolls of that magnitude were a thing of the past, as advances in the warning system should give people plenty of time to seek adequate shelter. It seems that with an incredibly violent tornado, however, there just was not enough adequate shelter in Joplin. As a storm chaser it pains me to hears about the death and destruction that tornadoes cause, and I'm glad I didn't witness this tornado, but instead caught an isolated rope out in the fields, that only Brindley, a handful of other chasers, and I witnessed.

 

Lessons Learned: 

  • Don't overlook areas of strong helicity ahead of cold fronts.
  • Don't be too quick to pass off good wall clouds as shelfy gust fronts.