Monster HP supercell northwest of Macomb, IL
Monday, featured a surprise local chase for myself. I had the day-off and was busy editing recent video and photos, but kept a close-eye on the local weather situation most of the day. This would later turn out to be quite important toward evening. A departing MCS allowed for rapid destabilization in its wake in SE Iowa and west-central Illinois...sound familiar at all? This area has been a hot spot this month folks! After some analyzing from home it was becoming more apparent this area was becoming rather ripe for supercells by mid-afternoon. 3,000J/kg of CAPE, Supercell composite approaching 20, and 0-6km shear around 50kts. After reviewing mesoanalysis most of the day and surface obs. and seeing agitated cumulus in SE Iowa I quickly got out the door headed westbound on U.S. 34. As soon as I get on the road a supercell quickly goes up in SE Iowa and goes tornado-warned sparked by an ejecting shortwave. At this point, I'm hauling west to get out in front of a massage HP supercell with it crawling towards the Mississippi River at 20mph. A few tornado reports come in along the river while I'm heading west trying to catch up. Eventually, I finally do and get a view of this beast west of Macomb, IL south of the town of Tennessee, IL with the sirens-blowin' alright! This storm meant business folks! The gust front and shelf became visible right away with a nice inflow tail getting sucked into the rotating updraft. I sat here for a good while taking many structure shots as it had some incredible structure at this point. I kept up with this HP supercell as it progressed southeast toward Macomb, IL all the way to its demise near the Illinois River. Along the way this supercell had some insane inflow that stretched nearly the entire northern horizon and looked like it could produce a damaging tornado with rapid and violent rotation. Other than a few funnel clouds and rapid rotation it never produced a stellar tornado at least that most of us (chasers) could observe however. Their may have been some brief touchdowns, but none that I saw for that matter. This beast seemed more outflow dominate than anything, but this sucker was sure rotating strongly all evening though. It was a hell of a storm to say the least! I've included some of the better structure photos I was able to grab along the way below:
Almost witnessed my first gustnado here...
look at that clear as day cone (left)
Trying to wrap up...
look at that clear as day cone (left)
Trying to wrap up...
Wide-angle shot of the cone extending from the gust front
This storm had some crazy rotation at times...
This storm had some crazy rotation at times...
Supercell becomes outflow dominate
as it approaches the Illinois River
as it approaches the Illinois River
I didn't get a tornado from this chase, but I'll always take supercell structure whenever I can get it especially so close to home. Stay tuned for another post featuring yet another chase.