afternoon outside Wyoming, IL
On August 9th, I had the day-off from work so I monitored the weather situation throughout most of the morning. After analyzing the setup and keeping tabs on model-runs over the last few days I thought that central Illinois still posed a severe weather risk despite low probabilities by the Storm Prediction Center (SPC). It did look as though the best severe potential existed in Indiana during the evening, but storm initiation would occur earlier in the day in north-central Illinois. This was where enhanced lift under the left-exit region of unseasonably strong jet stream would begin to punch into an unstable air mass. By noon, I had the gear packed up and began heading north out of Peoria, IL as the sun broke through some pesky low-level clouds. The atmosphere quickly began to become unstable with surface heating and a moist boundary-layer in place. I targeted an area less than a hour from home-base along the I-74/I-80 interchange where it looked as though convergence was increasing around 1:00pm. This target-area was characterized by nearly 1,500J/kg of CAPE, 0-6km shear increasing to 40kts, and a moist boundary-layer with dew points pooling near 70°F. I quickly found myself "laying back" though not wanting to show my hand too early. I spent a hour continuing to analyze near Camp Grove, IL at a local wind farm (rest-area). While here I began to see upward vertical motion increasing in the (Cu) field as well as the first "blips" on radar showing up to my northwest near Galva, IL. I let this "shower" intensify for a little bit than dropped down the hammer and headed west on IL Rt. 17 that would put me on track to intercept this intensifying thunderstorm. From here, I dropped south of Wyoming, IL after snapping a few photos as intensification continued. I would quickly get a great view just north of Duncan, IL of a developing supercell that had some mid-level rotation at times. At this point, it featured a nice wall cloud that was hugging the rural-Stark County landscape. I shot some photos and time-lapse video enjoying the view. I knew I had to keep up with this supercell as it continued to intensify so I preceded to head south and back east along familiar country roads north of Princeville, IL. This storm was rather photogenic initially when it got its "act together". As this supercell approached Dunlap, IL it began to encounter convection to its south which would mess up its inflow. By this point, it was mostly outflow dominate as it headed into Peoria, IL. I still kept up hoping for it to organize again farther southeast so I hopped on I-474 and blasted east to get out ahead of it. I stopped at Goodfield, IL to take another look, but I wasn't too impressed with the "blob" of convection it had now morphed into so I set my eyes on new severe-warned convection that was looking impressive to my north near Varna, IL. I headed northeast to catch this supercell along U.S. 24. By mid-afternoon, I caught up this supercell along I-55 just south of Pontiac, IL. I stopped at a rest-area along the interstate where I took some more photos and video of this supercell as well. This one slammed me pretty hard though with dime-size hail and wind gusts near 60mph. I couldn't avoid a "what the hail" moment on this chase day unfortunately. I got lucky with no damage to speak of though! After riding out that supercell another formed back to the northwest so I stopped for a good hour outside Flanagan, IL to shoot some more video and snap some more photos. This one was rather outflow dominate though, but featured a nice shelf cloud. At this point, the most severe convection was shifting into Indiana so I headed back west arriving back into Peoria, IL by 7:00pm. It was a rewarding chase and being that this day fell on another day-off was a plus. I've added photos and some time-lapse video from the chase below:
updraft in the distance...
Watched her blossom into a supercell right on cue!
Rapidly intensifying with a nice
well-defined wall cloud (right)...
Wide-angle shot of this developing supercell!
More blossoming convection!
Another portrait-shot as this supercell approaches...
One last photo north of Duncan, IL as I
head south and east to keep up...
Multi-tasking, as I snap this photo
of the wall cloud (background) a couple miles to my west
while letting the video camera time-lapse...
Its base a tad too high right now...grr!
Nice inflow here produces this needle funnel
Click to enlarge...
Inflow band!
Becoming progressively outflow
Pretty cool shot of these towers goin' up!
First view of supercell #2 southwest
Another well-defined wall cloud seen here...
A tease off to the right...
Never thought of including the video-camera
in a photo such as this!
One last shot of this supercell before
I get pelted with dime-size hail!
This was a supercell initially, but quickly became outflow
Another view...
One more photo of the departing convection of this
unseasonably strong August storm system...
I've added a YouTube time-lapse (above)
I've added a GoPro video (above)
I've added Part II of my GoPro video (above)
I've added a YouTube time-lapse (above)
I've added a GoPro video (above)
I've added Part II of my GoPro video (above)
Overall, I can't be at all disappointed in this chase day especially for August. Hopefully, we get some more chances before fall kicks-in soon. Stay tuned for more updates/posts...
