February 20, 2014
Statistics
Springfield, IL 1:01 PM 2/20/2014
Springfield, IL 6:41 PM 2/20/2014
Rope Tornado, RFD Clear Slot, Mammatus
Summary
Early season warm front setup across central Illinois. Targeted west central Illinois for low topped, semi discrete supercells. Intercepted fast moving tornado warned cell north of Winchester, noting RFD clear slot and apparent funnel which was later confirmed as a rope tornado via other chasers’ video. Intercepted new tornado warned cell near Illiopolis noting midlevel rotation and RFD slot but missed earlier tornado. Fell behind line of storms and called off chase after encountering snow covered road noting rainbow, fog, and mammatus along the way.
Crew and Equipment
Solo chase. Equipment: Canon 60D, Canon t2i, Canon EFS 10-22, Canon EF 50mm, Sony HDR-xr500v..
Video
Map
Details
The first chase of 2014 snuck up on me. The models had shown a big trough sweeping through the Mississippi valley on February 20, but it looked like instability would be an issue and the event over less than ideal chase terrain, so I wasn’t too keen on going after it. In the grips of one of the coldest winters in recent history, storm chasing and spring weather still seemed like a far off dream. Springfield got several inches of snow on February 19, but with the arrival of the trough and warm air advecting up from the south, much of it had melted overnight, and only patches remained by morning. The strongly sheared system prompted the Storm Prediction Center to issue a slight risk for tornadoes across the southern Mississippi valley, excluding much of central Illinois near the snow line.
A run through the morning short range models, visible satellite loops, and surface observations, and I was coming to significantly different forecast. It looked like a chase day across west central Illinois. Dewpoint temperatures were hitting 60 F near the surface low in Missouri. The warm sector was clear ahead of the cold front, allowing it to destabilize with forecast CAPE values exceeding 1,000 J/kg. A robust arc of towering cumulus was going up across central Missouri, heading for western Illinois. A warm front extended off the low across central Illinois with a super strong low level jet. Helicity values were over 400 in parts of the warm sector. The tornado parameters were spiking. West central Illinois was completely out of SPC’s outlook, but after seeing those plots I scrambled to get the van ready for a short notice storm chase. I fired up the laptop, connected all the hardware, gathered my cameras, and miraculously everything was working.
A couple lines of cells were crossing the Mississippi and moving into Illinois. The extremely strong jet was whipping the storms northeast at speeds of 60 mph. The plan was to head west on 72 and catch the cells as they crossed the interstate, and then head east, catching other cells moving up from the south. At those storm speeds, keeping up with any of the individual cells would be nearly impossible. I was surprised to see all of the snow that remained on the ground as I headed west. The solid snowpack was not far to the north, which would rob the cells of the surface based instability needed for tornadoes.
Rounding the bend at Jacksonville, the storms started to come into view and my heart ached for spring at the sight. An anvil stretched far overhead, and the western horizon darkened.
I moved in for the intercept, racing down to 72 to catch Tail End Charlie in the line before the severe warned cell crossed the highway. The base came into view, low to the ground, with not particular impressive structure in terms of supercells, but I wasn’t expecting much given the modest amounts of instability.
The storms raced across the highway and rocketed off to the northeast. Near the Illinois River, there were no good roads north to keep up with the cell. I turned around and started heading back east to catch the next cell coming up from the south out of the St. Louis area. I watched the cell I had just left recede to the north and could make out what looked like a rather classic rear flanking downdraft clear slot on the back of the updraft base, unexpected supercell structure.
The storm was pushing more than five miles away at this point, but I swear I could make out what appeared to be a white point extending out of the north end of the horseshoe base. A funnel cloud? I had to be dreaming, desperately yearning for spring and seeing things on the horizon that weren’t there. The storm went tornado warned with a spotter reported funnel cloud.
Now I was amazed. I was pretty sure I had captured that funnel cloud even though I could barely see it. A couple minutes later, I got a report of a tornado on the storm. I couldn’t confirm at the time due to the distance and trees blocking my view of the ground immediately underneath it, but I had indeed captured the tornado on video, the rope funnel barely visible at that distance. My first February tornado was like a dream, a distant vision on the horizon, a metaphor for the coming Spring.
Invigorated by what I had seen, I pushed on to intercept the next cell coming up from the south. Perhaps it too would tornado as it approached the warm front. I raced east away from Springfield down 72 for the intercept. The storm went tornado warned. I stopped downstream of it on the ramp near Illiopolis. Grungy low clouds streamed past overhead as I waited for the storm to approach my position. The southwest sky darkened . I got out of the van to watch the sky. The base was still not in view, but strong midlevel rotation was evident in the storm’s updraft tower. I appeared to be directly in the path of the center of the rotation. With no view of the base, I decided to pull the trigger on my escape route.
I headed a couple miles south to clear the path as the base started to come into view, super low to the ground.
Once I had my bearings I approached, and the southern end of the updraft base passed overhead. Sunlight streamed through the rain on the back end casting sepia toned shades of light.
I turned around to make a futile effort to keep up with the cell. Another prominent rear flanking clear slot was prominent on the storm, but this time there was no tornado.
I ran east to intercept a line of cells in front of me. In their wake, the skies were a featureless grey as it rained. The ground was blanketed in a creepy layer of fog caused by the snow cooling the saturated air.
I turned south as I finally had visibility on the base of Tail End Carlie on this line of cells. I turned east to punch the line from behind, but my road was covered in snow up ahead. I stopped and briefly considered attempting to push through the snow, but decided it wasn’t worth the chance of sliding off the road and getting stuck in the mud or worse, so I decided to turn around and call off the chase as I was now hopelessly behind the fast moving line of storms. It was the first time I’ve had to turn around while storm chasing because of snow.
Heading for home, the sun started to peak out from under the storm clouds and trailing scud, lighting them up in golden shades, with patches of fog at the ground. The show in the sky wasn’t over, even though my chase was.
Emerging from under the low level clouds I could see the anvil of the storm complex stretching overhead with a layer of textured clouds underneath.
Golden mammatus in the sunset as I head west into clear skies away from the storms. What an amazingly well rounded and beautiful start to the 2014 storm chasing season.
Conclusion
What began as an unexpected start to the chase season turned into my first February tornado intercept, even though it was difficult to see and confirm at the time. Storm chasers Dan Robinson and Paul Hadfield got better shots of the rope tornado near Jacksonville, which helped me confirm that I had captured a tornado in my video. The rope tornado was rated EF-0 and was one of several that occurred in central Illinois along the warm front and near the snow line. The snow may have played a part in the tornadogenesis process, perhaps positively by reinforcing the warm front or negatively by acting simply as a northern cut off point of the low level instability. Even though the tornado was one of my least photogenic, the chase was rich in visual spectacles from fog, to rainbows, to mammatus. It was a teaser for the spring chases to come, a tornadoes on the horizon.
Lessons Learned
- Don't forget to use your telephoto lens for those distant tornado shots.
- You can see tornadoes even with patches of snow still on the ground.
