A (HP) high-precipitation supercell spins to my north near Walnut, IL
On June 22nd, I spent most of the day at work until the early-afternoon when I got off work. After monitoring the potential for severe weather at work and for a few days prior I decided that this was a day to storm chase or you would regret it. This day featured some of the best ingredients for severe weather and tornadoes all spring and summer for myself when I was available to storm chase. It seemed everything was coming together for a possible tornado outbreak well north of Peoria, IL especially across portions of northern Illinois. I got off work by early-afternoon and began heading north on I-39 with a initial target near Oregon, IL. Some lingering convection along a warm front kept the front more aligned near the I-80 corridor so I quickly decided to change my target after analyzing surface maps during the afternoon. I ended up sitting nearly on the warm front north of I-88 in Sterling, IL. This area along the warm front was primed for severe weather including supercells and tornadoes. Along the warm front featured 4,000J/kg of CAPE, 0-6km shear at 65kts, 400m2/s2 of 0-3km storm relative helicity, a supercell composite of 28, the significant tornado parameter at 8, and a very moist boundary-layer with dew points near 75°F. I had very high hopes on this day as it had been awhile since I had succeeded in photographing a tornado. I spent most of that afternoon waiting for the atmosphere to continue to destabilize and a shortwave trough to ignite convection along the warm front. By evening, convection began to initiate nearly overhead along the warm front. Showers quickly became supercells with intense CG lightning strikes and low-level rotation. In fact, these supercells had some pretty large mesocyclones due to the strong shear in the low-levels and upper-levels of the atmosphere. As these supercells began to form I began chasing the farthest east supercell along the warm front near Sterling, IL. This storm had decent rotation, but it became apparent to me that you would have to keep sampling supercells driving farther west as this storm I felt like was gonna get munched up by another supercell to the west. Despite this supercell looking pretty good, I made the call to leave this storm and head southwest to an intensifying supercell near Walnut, IL. This HP supercell had some amazing storm structure as I was quite pleased with its rotation as well. Unfortunately, another storm was developing to the west of this supercell as well and I feared that this storm may contaminate this supercell's inflow. Therefore, I headed west on IL. Rt. 93 to chase the 3rd supercell of the day. This supercell near New Bedford, IL quickly went tornado-warned upon my arrival. It had really good inflow and a very low wall cloud at one point. It sure was spinning and funneled on a few occasions. I then found a spot along a farm field to watch this storm's rotation as it was very close to producing a tornado. Finally, this storm decided to drop a quick and weak tornado to my east near New Bedford, IL as I was in the RFD rain curtains at this time. I captured a few shots of the barely visible tornado that was rain-wrapped. The tornado quickly lifted from a Illinois farm field and unfortunately I was losing more and more daylight. As the sun began to set I then decided to begin heading back home to Peoria, IL after a successful chase day. Here's a radar loop from the chase day here. I've added photos from the three supercells I chased below:
Mesocyclone on this supercell just prior to producing a brief tornado near New Bedford, IL
The first supercell begins to spin near Sterling, IL
Supercell #2 near Walnut, IL
A wide-angle shot of this HP supercell!
Awesome storm structure!
Quite a bit of water in this supercell!
Large mesocyclone!
Some great storm structure!
Quite a beast of a storm!
Another wide-angle shot!
"Here comes the rain"
Supercell #3 to my northwest!
Good rotation and inflow at this point!
Closer-view...
Funnel! (left)
Still spinning...
I had to be very careful as some dangerous lightning strikes were occurring...
Inflow increasing...
A lot of spinning going on at this point!
It's getting closer to producing...
Nice inflow and funnels!
"Angry spinning skies'
A tornado forms near New Bedford, IL
A weak rain-wrapped tornado to my east...
One more shot before the tornado quickly dissipates...
This was a successful chase day for myself. I've added a write-up from the National Weather Service (NWS) out of the Davenport office (DVN) found here. Storm reports for the day can be found here via the Storm Prediction Center (SPC). After a couple weeks of down time I photographed some local firework displays during the 4th of July holiday and I will post those photos in upcoming posts soon.
