Early on Thursday the 11th looked
like a big minisupercell day across Illinois and Iowa. However, as the
day drew nearer things did not look as favorable. A warm layer at H7
was killing off much hope of deep convection, and surface winds were
slowly veering and weakening across the target area. These things do
not add up to a very favorable March severe weather setup. I already
had the day clear of plans for a potential chase and was visiting home
for spring break and was already in decent position, so I continued to
monitor things at home in Champaign. Morning
water vapor imagery showed the cyclone centered over Iowa, with
morning thunderstorms retreating north into Wisconsin, Indiana, and
Kentucky. The mid level dry punch had worked it's way into Illinois and
Iowa and was allowing for insolation, but at the same time rapidly
mixing out low level moisture from west to east across the state. Surface
data from 3 PM showed moisture rapidly mixing out in western
Illinois with dew points now in the low 40s, with surface winds
beginning to veer out of the southwest. Eastern Illinois held on to mid
50's dew points however, and surface convergence was forecast to
increase towards sunset so I kept my eye on the satellite. Sure enough,
around
5 PM surface winds really began to converge right around my
location in eastern Illinois. Satellite imagery began showing an area
of agitated cumulus along the Piatt / Champaign County borders, with
storms beginning to initiate further north towards Kankakee. A few
returns began showing up in my area of interest just west of Champaign.
I watched from the front yard as one area really began taking off.
After a long winter this alone was enough to get me in the car for a
short drive. Tia decided she was up for a quick outing and hopped in
the car, and we were off.
This area actually began to organize fairly quickly, and by the time I
had headed north out of town on Route 45 a fairly substantial low
topped storm was underway just north of Urbana. Storm motions were very
slow for this time of year, so I was able to easily keep ahead of it by
stair stepping northeast along the county roads in northern Champaign
County. Unfortunately, things got off to a late start on this one so
our time together was limited before the sun began to set behind the
pretty storm. The core actually strengthened healthily and produced pea
sized hail which covered the ground in Thomasboro. Staccato lightning
bolts also accompanied the storm at sunset, which was quite a treat to
sit back and take in. March storm chasing is often -very- frustrating
with low visibilities and fast storm motions, but this one was neither!
A beautiful updraft tower and rain free base with storm motions that
could not have been over 20 mph. That being in my home stomping grounds
of extremely flat Champaign County and familiar roads were the icing on
the cake in this first convective outing of 2010. Once the sun faded, I
headed back towards town. Not before catching a glimpse of the storm in
the twilight in the distance and having to stop once more for a couple
photos. Tia and I were hungry as it neared dinner time, so we detoured
to Chili's for a dinner where we played a role reversal as she devoured
a massive burger, and I played it safe with a tasty pasta.
I wish the minisupercell outbreak had materialized, but short of that I
can't think of a better way to start to the 2010 warm season. After the
year of stress 2009 was, let's hope this is a good omen.
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