May 17, 2000: Nebraska

05172000map.gif (19851 bytes) Web Posted 10:00 PM June 4, 2000.
by Amos A. Magliocco

   We left for Oklahoma on May 15th, a Monday, Blair Kooistra and I having convinced one another that chasing with little hope of storms was better than staying at home with none. We knew Nebraska would be our target for the next two days, and SE Oklahoma, where some instability and marginal surface convergence held the slim possibility of storms, was on the way.

We met up with Glenn Dixon at a gas station in West Texas. Glenn was doing a damage survey for the Weather Service and hadn’t planned or packed for an extended chase. Swept up in the spirit of our adventure, he called his wife back in Dallas and followed us north towards the High Plains. We filmed bombers practicing touch and goes near Altus, Oklahoma and slept in Woodward, never having seen a cloud the entire day.

  
 

Tuesday the 16th held more promise, and the Storm Prediction Center issued a moderate risk for Western Nebraska, Northeast Colorado and Southeast Wyoming. The intersection of a dryline and northbound warm front beneath an incoming upper level jet was our target, and we drove through Kansas to Southwestern Nebraska. Storms fired well to our west in Wyoming, but it was too far and too dark for us to pursue. While the next day held the most promise of the trip, I was disheartened and a little exhausted from the drive, and chose to spend the night in Julesburg, Colorado, where we’d finally stopped for dinner. Wisely, the others wanted to move east before getting a room, expecting action in Eastern and Central Nebraska the next day. I wouldn’t drive another inch, looking forward to an evening of reading and writing and not thinking a whit about the atmosphere and how it eluded me for thousands of miles, leaving me stranded in a near ghost town on the abandoned plains of Northeast Colorado.

Blair loaded in with Scott Eubanks, and along with Eric Nguyen and others, headed east to make North Platte for the night. I knew the larger group would be easy to catch up with the next day.  My indecision lasted as long as it took to get a hot meal, a shower, and a phone call from a pretty girl. I was looking at the models before I went to bed, amazed at the next day's possibilities.

Wednesday looked like a sure bet for tornadoes. A warm front moving the from the south and a strong dryline budge forecast to slide east into Central Nebraska attracted hundreds of chasers from all over the plains. Most of them stopped for data in a truckstop near Kearney. It was after 2:00 PM and I had caught up with Blair and the others on the interstate a few hours before. We looked at data and saw the situation was changed little: the dry punch was strong, and cumulus were forming along the leading edge in the warm sector. A powerful surface low was sliding into Western Nebraska also, and a classic triple point seemed likely. Playing the textbook, (who am I to throw out the book?) I decided I should continue east from Kearney, stay ahead of the dryline and in position to intercept storms forming to my west.

My first mistake was failing to consider that the split flow aloft would take storms that fired in this region (still Central Nebraska, really) either northwest or due north. I hadn’t gone far enough east to be under the southwesterly flow aloft and so my plan to catch the storms as they moved northeast with the steering current was fatally flawed.

I set up shop near Minden, southeast of Kearney and chatted with local ham radio operators as they watched the sky and prepared to activate their spotter network. One of them, Brian Hartmann, drove south from Minden to wait and watch with me. When the storms fired to our east, the first convection on the dryline, we debated whether or not to pursue. Having heard that these were moving northwest, I assumed they would cruise away from the most unstable air, and, being northeast of the surface low, subject themselves to cool, northerly inflow.  I didn’t think they would become tornadic under these conditions, and I didn’t want to get drawn so close to the dryline that it might overtake me.

My forecast for the dryline positioning was based on that morning’s RUC, which was very aggressive with the easterly track of this feature and fast, and so Brian and I held firm, twiddling our thumbs south of Minden while Blair and Scott tore through gravel roads and mud to catch the Furcas storm as it lowered a large, stovepipe tornado. An exquisite updraft base drew them north to the interstate, where they filmed that tornado and another.

Brian and I spoke with hams at the Hastings NWS, who told us there was no activity in their entire warning area. We moved north toward Interstate 80 and watched a line of cumulus emerge in a line from east to west. Brian and I agreed these were quite far, but they continued to impress, and seeing nothing else beyond the prospect of a third, terrible bust, I pursued the first storm north toward Elba. Within twenty minutes, this was a sculpted supercell, with a crisp anvil and a prominent overshooting top. Still, it was well north of me, and moving quickly northeast. Near Greely, I stopped and watched the storm move beyond my range. I learned that the beautiful country north of the Platte River is a sea of rolling hills where a clear view of a  thunderstorm base is nearly impossible. I stopped for gas and a snack.

05172000a.jpg (61326 bytes)
First supercell of 5/17/2000, which later caused damage in Greely, NE
 

I pulled up a radar image on the laptop and saw another storm was to my southwest, gaining strength in Buffalo County and moving due north: forty miles per hour was the reported speed. I thought Loup City to my west made a sensible intercept point, and I moved over the detoured roads and gravel trails between Ashton and North Loup. I drove fast and the storm came up alongside me, a black supercell racing north and I accelerated to keep pace, desperate for a glance between the hills. Twenty minutes of this and Hastings issued a tornado warning as the cell approached Ord. I was moving north beside the storm. State Road 11, however, was soon to curve northwest into Ord, bringing me right into the path of what looked to be an HP supercell. I knew if I wanted to make Ord before the storm, I would have to go faster.

I beat the storm to Ord by minutes. The core was jet black and broiling, with fantastic vertical motions as the storm ingested low-level scud. The storm had exhibited this aggressive inflow for over ten minutes, and I knew it was well wound as it approached the town. I looked around for anyone in the village, wondering if they had sirens, glancing behind me every few seconds at the wall of air and water churning towards Ord from the south. I never saw a soul, and I never saw the base of that storm: there was a not a single point when the updraft base was clear of the sloping hills. This storm might have carried a tornado for most of the sixty miles I chased it, and I would have never seen it. From Ord I went northeast on 70, and pulled well east of the storm, which grew outflow dominant. I watched the gust front crawl north, and gazed at my map in wonder that I was only 100 miles from South Dakota.

Blair and I started for home the next day, refueling in Grand Island with a cold and uninviting north wind showing us the door.