Saturday morning looked like a good day for severe weather just to our south and west.  Well within a couple hours drive.

A moderate risk was issued for a narrow corridor across hoosier alley.  SPC handed the area a 10% risk of tornadoes as well.   We decided that our target area for that afternoon would be somewhere in the neighborhood of Dwight, IL.  This turned out to be a eerily accurate decision. 

Having been burned by using SPC alone to determine a target area several times in May, we decided it was time to look directly at the models, and learn to use them to find the characteristics we needed for a good intercept.

Example of a forecast model for
determining sheer profiles
We made our way to Chicago, then south into Kankakee, IL.  Storm initiation had not yet begun, there were however a few small convective rain showers appearing south and west of Davenport, IA.   We made our way through small Illinois towns on route 17 and continued to I-39.  We arrived at I-39 in Wenona and took another look at the radar. Sunset was less than a couple hours away and only a few modest thundershowers had approached from out of Iowa and were now over the Kenowee, IL area.

At this point is was beginning to look like a bust.  We ventured North on I-39 with the intent of closely following a northern tundershower along I-80 and head back home. Just after we had gotten ourselves onto I-80, two of the thundershowers had quickly exploded into some modest severe thunderstorms. Within minutes, rotation appeared in both of them. A 3rd storm near Galesburg had become Tornado warned.  We began to slow the car down watching for an exit to pull of and make a decision. Before we could do this, all three storms were now tornado warned, with the southernmost storm already having a tornado report to the NWS.
Base Reflectivity and Radial Velocity west of McNabb, IL
We rushed back to I-39 as fast as we could. The northern storm was approaching the interchange, however this northern storm was not as healthy as the storm to it's south with clear air near it's hook.  Of the three storms to choose from, we decided on the one in that was in the middle with the clear air.  That meant punching it's core to make it Lostant before the storm did. By now a very healthy rotation was visible on radar, a tornado looked imminent.  The storm was moving ESE, we anticipated the southern component to the storm so we overshot it to the south a tad, believing it might be a little close for comfort, and with darkness beginning to settle in, that would not have been a good thing.
Wall Cloud. The NWS says an EF0 tornado was on the ground East of Magnolia, IL while this image was taken.
We arrived in Lostant and looked for a good spot to watch the wall cloud form. We began recording video. A lowering was visible to our North and West and it appeared to be rotating. We followed the rotation with the cameras as it crossed I-39. No distinct tornado or funnel was visible. We crossed I-39 and chose a lonely east-west road a mile south of route-17. The idea being that there would be less interruption from oncoming or following traffic than on 17. We also though the storm was continuing to nudge south. That was not the case. We had a LEFT mover on our hands! That can mean only one thing, There must be a tornado on the ground right now. 

We pulled over breifly at 179 and 8th road. By this point it was very dark. However each stroke of lightning revealed a classic mothership supercell was now in progress.  Suddenly power flashes were visible. Time to move! We continued east, still expecting the storm to cross ahead of us drifting south.  We paced the meso continuing down 8th road, continuing to film. Suddenly it became apparent that there was definitely a tornado in progress, and it was hitting structures.  Power flashes were frequent. the power in fact went out around us in unison with a larger power flash, indicating a main feed wire must have been cut to the area.  Since it was dark, our only indication of what was happening was numerous lightning strikes illuminating the funnel the Meso and power flashes at the ground.
EF2 Tornado damaging Streator (debris)
See below for a map of the Steator, IL EF2 tornado path and damage.

View Streator, IL tornado in a larger map
We continued to follow the Storm east. However now it appeared the there was no longer a tornado.  Radar images continued to show a healthy storm with plenty of Rotation. But now it was headed right for the town of Dwight, IL.  Moments later, more power flashes appeared. This time it seemed much closer to us. We couldn't see anything, but the camera was still taking video. Whatever was happening was getting recorded, we could only hope there was something to see in the footage later on.
EF3 tornado in Livingston County, IL
Damage Path near Blackstone, IL. Click for SPC's full damage survey
We approached the town of Dwight, only now it appeared that the Tornado and Meso must be ahead of us. The power was out in town and there was significant damage.  Scary enough, it appeared that the tornado had gone through the very town we stopped at for some subway just a few hours earlier!  Needless to say now, our forecasting had gotten much better this time around.   We discovered that, by using maps from models such as the RUC and NAM, we were now able to put ourselves more accurately in the zone than just using spc's forecasts. 
The supercell we were following turned very High Precip and was becoming incorporated into a newly formed Derecho from behind.  After encountering extensive flooding in the Kankakee area, we headed north.  June 5th turned out to be a major tornado outbreak. Overnight fatalities were reported in Ohio due to the same storm system.  Tornadoes were also confirmed overnight just a county away from our homes. The supercell we abandoned in Kankakee went on to spawn an EF3 tornado in St. Anne, IL as well.
As our first chasing experience of 2010, We had few expectations for a great storm to unfold.  We aren't experts. Certainly inexperienced. Quite hopeful though!   We had been planning this week long chasing adventure for several months.  We paid close attention to each event in April and May leading up to our week. 

Friday night, May 21st we made the desicion, based on SPC forecasts, to target northeastern Nebraska. This was, according to SPC, going to be a battelground for supercells late in the afternoon on the 22nd.  We made the decision leave at 4 am Saturday morning so that we could arrive in the target area long before storm initiation.  Sheer profiles looked good, CAPE looked good. Everything was ready, we just needed to get there.

By late morning, we had reached Davenport, IA. Doubt began to set in. SPC released it's updated morning forecast. But this time, the target area was starting to look better in the Souix Falls, SD area.  As the drive down I-80 went on, we made a last-second decision to head north up to I-90 and continue west into eastern South Dakota.  By mid afternoon we had arrived in Mitchel. To a cloudless sky, temps in the upper 80s, and high humidity. What storms? The weather was beautiful.  The radar was blank. The sattelite imagery showed little if anything. 

Watching some feeds we noticed that some chasers had positioned themselves in the same general area, while others were positioned further north, in the Aberdeen, SD area.  How odd. What were they doing up there? SPC had mentioned storms in that area of SD, but later in the evening.  We decided to get some RainX and a new air filter for the car while we waited for something to happen. However it was well after 3 PM and initiation didn't look imminent at all.

Finally a tornado watch was issued. Both for our location, as well as a large area to our north and to our south
Just then. Something began to erupt. We just weren't watching

After performing a quick tune up, and just 20 minutes later, I looked again to the radar screen and noticed that a fairly vigorous, lonely thunderstorm had appeared far to our North near Gettysburg, SD.  I looked north through the trees, I couldn't see anything. Not thunderheads, not even a single whispy cloud. Then I saw that everyone on was now headed in the direction of this new storm. Few of them were in good position, but they were clocking very high speeds on SD's generous, long flat roads. 

There was no way we were going to get there in time. It's WAY up there. easily a 2.5+ hour drive.  We decided to begin trekking north. Hoping that something would initiate further south that we could catch up with. We were well ahead of the front but perhaps we were still too far south. 

Quickly the storm moved into the Bowdle area and exploded into a textbook supercell. and was soon tornado warned. The storm was joined by a few weak neighbors to it's south, neither of them as interesting as this storm.  We picked up our pace. Unfortunately the storm had a bit of a northerly component that kept it well ahead of us. If anything we'd have to meet up with it in NORTH Dakota.  Then we began to realize this storm was becoming a right-mover... heading more east than north.  It looked more and more like we could catch the storm in Ipswich within about and hour-and-a-half.  If it held together that is!

Then news began to pour in on this storm. "A Large, Dangerous, Violent, Wedge, Epic, Win, Long-lived, storm-of-the-year, Comegetme" Tornado was on the ground. We were hauling as fast as we could. Soon we were under the canopy of the Anvil of the storm. Tornado reports continued to pour in for towns east of Bowdle.  We decided on a rendezvous point just west of the town of Ipswich.  Unbelievably the storm slowed down, continued moving west, only. And continued to be alone without competition of other storms.  What seemed impossible over an hour ago now looked within reach!

Positioned east of Ipswich we waited for the wall cloud to pass over us. No funnel was in sight.  As the wall cloud continued overhead we chased it further east several miles as night settled in on us. Just before dark though, a well defined funnel appeared, but never quite reached the ground. Just as we began to get ahead of it, we ran into a road-closed sign, darkness completely fell, and the chase was over.  We didn't come away completely empty handed. Not only that, but we found ourselves in Chaser's dream storm. Everyone was there, including the more famous personalities featured in Discovery's Storm Chasers show.  We soon learned that Reed Timmer and the Dominator, Tim Samaras, the TIV where all on the same storm and had collected a huge trove of data. And here we were, minutes away from catching up to the same Tornado. 

Our whole day was reviewed in our heads...if only we had skipped the stop in Mitchell, if only we had headed North on I-35 instead of west on I-90. So many things we could have done or should have done. In the end we were just happy, and felt lucky, that we had picked the right week, the right day, the right state...and almost the right place at the right time.  Check out our video showing the drive up through Redfield and Aberdeen to THE storm of 2010, and what remained of the Bowdle EF4 Tornado.