2/28/17 Tornado near Washburn, IL

2/28/17 Ottawa and Washburn, IL Tornadoes

I watched with instinctive terror what was tearing apart the field in front of me, a dark-matter dust devil maddeningly cycling away. Inky black dirt whipped into the tornado, cloaking it in ugly clouds that shed off into curling tendrils. It picked up its pace and stumbled angrily through the field in front of us as if in a temper. When we looked back, all that was left was a floating cloud of dust, like a demon banished with a spell.

The night before, sleep did not quite come easy. My mind was racing through the possibilities of what we could see tomorrow, with the unsettling feeling that large, long-track and even deadly tornadoes could be roaming by nightfall. After much deliberation, we chose a target of Ottawa, IL, close to a differential heating boundary reinforced by a couple morning storms. When we arrived, a number of cells had already fired. Three prominent clusters formed, the tail end of which seemed the most intriguing, just having that look like it could last forever. Keeping these in mind though, we chose to check out the northern cluster first, which was rapidly strengthening.

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What struck me the most about this storm was the lightning. It was constantly rumbling, a strange sound in late winter. One of my chase partners let her hair down so we could see when the electricity in the air became a bit too much.

We fortunately chose not to gamble with this storm that would later produce an EF-3 tornado that hit the south side of Ottawa, IL. Following a high-precipitation supercell through a river valley with horrible road network and dense trees lead to deteriorating safety, so we decided not to keep up with it despite its obvious gearing up to produce a significant tornado. Mostly, however, it had that grungy, bland look to it that seemed uncharacteristic of such a day, and that suggested it wouldn’t be hard to find something more visually appealing.

As we fled south out of its grasp however, a twister seemed to drop out of nowhere less than half a mile from us near the town of Standard.

2/28/17 Tornado near Standard, IL

It was anything but “standard”,  a random spin-up along the rear-flank downdraft of the massive Ottawa beast. What appeared to be a tornado was just a tiny circulation around the main powerful mesocyclone.

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The elephant trunk funnel snaked all the way to the ground at times.

We jumped around a bit to sample a couple more tiny tornado-warned storms drenched in rain, until we realized it was time to finally dive down to the long-lived, “tail-end Charlie” supercell that had been cruising steady state for the last couple of hours in our direction. We started driving south, anxious to see an isolated, picturesque beauty of a supercell. We were not disappointed.

2/28/17 Supercell near Washburn, IL

It almost wasn’t surprising how perfectly sculpted it was, a rock-solid look revealing layers of rotation. This storm had to work with over 1500 J/kg of surface-based CAPE, around 60kt of bulk shear and upwards of 200m2/s2 of storm-relative helicity in the lowest levels; it had everything it needed.

We reached the top of the hill, and I began to get this amazing feeling, half relief that we had escaped the troubles now worsening in Ottawa, and half relief that we had this gorgeous sight in Washburn almost all to ourselves, with few if any people living in the path of what could soon be a powerful storm.

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Within minutes the scene was altered by a faint swirl of dust on the ground underneath the base of the storm. Timing had worked out perfectly – this storm had trekked hundreds of miles across Illinois; why it chose to wait until now to unleash its brief but incredible fury was a matter of luck.

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The dust thickened.

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A local left town as the dust loomed before it.

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Another one fled the scene.

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Thin ribbons of vorticity danced inside the dust.

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We decided to get a bit closer, just as the twister sucked a sheath of black dirt up around its dark funnel.

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Quickly it became a tangled mess of darkness.

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The cloud became massive as it sucked up everything in its sight. It became nearly impossible to hold the camera steady with inflow whipping into the circulation.

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A line of dust whipped into the tornado delineating a powerful “ghost train” rear inflow jet.

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It took on a thick cylindrical appearance as it began to shed off its curling cloak.

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The inflow tore into the tornado, wrapping up around it.

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It looked like a nightmare.

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Out of nowhere, a car shoots by before it, miraculously unscathed.

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As we looked overhead, the parent supercell’s mesocyclone curled perfectly around the widening ball of dirt, dust and debris.

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The long, tiny white barn in front of it was gone 30 seconds later with a roar like a vacuum picking up gravel.

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That barn is now inside. In a hurry we raced toward it, checking in on the house to make sure everyone was alright. Two barns were destroyed, but the house still stood stoically with just a few scratches and broken windows. Everyone was safe.

2/28/17 Supercell near Dwight, IL

We continued following the rotating storm. It corkscrewed and tilted forward as it glided steady-state for hundreds more miles, driven mechanically by powerful wind shear as if it was engineered to go on forever.

2/28/17 Shelf cloud near Streator, IL

Finally we allowed ourselves a more tranquil scene as the final squall line raced in a few hours later. Nothing really could last forever; the day could now be over.

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