Friday, March 12, 2010

03/11/10 March Begins the Madness

Thunderstorm rumbling outside Toulon, IL yesterday

Thursday, I ended up "dusting-off" the chase gear for a local storm chase after a long winter in this area. The day showed some signs of promise a few days before the event, but many factors limited severe weather on this day. A mid-level dry slot allowed for some destabilization behind the morning rainfall. This would later set the stage for some isolated t-storms by midday in central Illinois. Around 11:00AM cumulus started to build ahead of a weakening cold front. I debated traveling to southeast Illinois early in the day where more instability (CAPE) would be found later in the afternoon, however I decided not to after seeing a subtle thermal boundary set up just to the north of Kewanee, IL. I figured if something could develop and latch on to this boundary it might produce a weak tornado and with this area being so close to home the decision was easy. Furthermore, this area seemed it would hold on to the SE surface winds a little bit longer so it became a easy call to make. The first storm developed shortly after 11:00AM south of my location near Canton, IL moving north. I preceded to head south and east so I could get a decent view as it moved north near the town of Toulon, IL in Stark County. At this moment this storm was in a weakening-phase and I could feel the cold out-flow...doh! After observing and shooting some video I drove east outside the town of Elmira, IL where the storm quickly began to show new signs of life visually. This storm was starting to get a tad more interesting with each GR scan coincidentally as it approached this thermal boundary to its north. I than drove east and preceded north on Rt. 40 which leads into Buda, IL and intersects I-80 outside Sheffield, IL. The storm looked decent along the way in some instances and as I crossed I-80 there was a moment I thought this thing might produce my first march tornado as it seemed like it was starting to get some surface-based parcels at that time. As quickly as it turned from a crappy storm to something interesting it quickly fell apart again and I decided to let it go at that point realizing that it wasn't going to produce on this day. Why were yesterday storms a let down? Well, in my opinion several factors limited storms from developing and becoming severe/tornadic. It seemed the convection that tried to develop in central Illinois really struggled to become surface-based. Usually, you're lacking at least one key ingredient this early in the year which contributes to a boring chase day. With that being said another factor that didn't help with storm organization was how quickly the surface winds veered from southeast to the southwest throughout the day. Also, this was a long-skinny CAPE situation and since we didn't have enough CAPE in the low-levels this contributed to the lack of low-top supercells as well. You have to have all the ingredients come together for tornadogenesis and this wasn't one of those days in turned out. I've added a few photos from the brief chase below:

Rain shaft becoming more pronounced at this moment
First view of the storm approaching from the south
Weak circulation aloft on the edge of this intense rain-core
Strongest at this point outside the town of Sheffield, IL
I took this shot Wednesday evening...spring is here!
Convection, I was previously chasing nownearly 50-miles away from home
Rockin' robin
I've added a short YouTube clip of the march convection (above)

Thursday, ended up being a good start for testing out new equipment and getting back into the swing of chasing storms. I had already forgot how exhausting even local chase days can be as your brain is literally fried from forecasting. Nevertheless, I grabbed a few photos here and there and shot some video knowing that there are better days to chase in the next few months ahead...