Jamie and I started the day by meeting up with Bob
Conzemius and Scott Woelm at SCSU, at Bobs office. We then
headed out with Meredith Lindrud and Theresa Caspers, and also
met up with Don Lloyd, who was also chasing. The following is
account of the chase with some additions from me.
We drove west-northwest to Alexandria through a pretty solid
stratus overcast, with surface winds at our backs, and clouds
moving left to right across the road, so the low level shear was
quite incredible. As soon as we got there, a severe warning was
issued for our county (Douglas), but we could see nothing through
the stratus. A look at TV radar showed this was a supercell. Since
the storm was coming right down I-94 at us, we decided to duck
south a bit, then west to find the updraft base. The skies cleared
briefly to our south to reveal a VERY healthy anvil rapidly overspreading
the sky. Seeing clearing to our south, we knew this storm was
very close to the warm front and had at least a chance of producing
We finally intercepted the storm about 15 miles west of Alexandria.
Our only real visual clue we were getting close was the blackening
stratus deck to our northwest, punctured by frequent staccato
CG bolts. As we drove nearer to the heart of the darkness, we
finally saw a broad, circular updraft base reveal itself through
the the dark haze to our west. The base looked mean,
with some precip curtains in it, yellowish backlighting, and RFD
trying to punch through. As we set up on tripod and filmed, the
base quickly became filled with rain, and our easterly inflow
winds became cooler and more northeasterly from the core. Perhaps
it was already time to abandon this one and drop south, hoping
for more cells to to come from the west, while still keeping an
eye on the notch to our original storm.
Once we dropped south, it became clear what to do. Another, stronger
updraft base was immediately to our west-southwest, the low stratocumulus
were screaming right into it. This updraft seemed to be ingesting
higher theta-e air, and we could see blue skies to our south (the
capped steambath). We dropped a little bit south, then moved east
and south with it. The storm was mostly in the HP process with
a circular updraft base mostly filled with rain and RFD shelf
cloud wrapping around the southern side of the base. A tornado
warning was issued for our new cell. We ran ahead of it a bit,
stopped to film until the outflow/RFD hit us (not very cold),
then blasted east again to get back in inflow.
When we were a few miles southwest of Lowry, a tornado was reported
on the ground with our storm. We saw a couple tube-like rain shafts
to our north but nothing tornadic. We proceeded east while lamenting
these goofy tornado reports but wondering at the same time if
we were totally missing something.
After this, the main core got closer, the storm looked a little
more linear, and very strong northerly outflow winds were shaking
my car. I thought our supercell show was done. Our road (County
24) took us into a fairly deep lake valley with a few curves,
and I realized this might have upset my sense of direction for
a bit, for when (in Glenwood) I looked back behind me, the low
stratus had disappeared, and the grungy sky had opened up to reveal
a wonderfully banded updraft vault with a
thick inflow tail on its northeast side (second
view). Another band of inflow stratus was immediately to my
south and screaming straight in to the updraft. We pulled out
of the valley and stopped to look westward over Minnewaska. Since
frequent (positive?) CGs were popping very near, we had to stay
in the our cars.
I briefly hopped out to get a couple stills, then an RFD punched
into the mostly rain-filled base. A somewhat ragged, cone-like
lowering slowly descended just to the north of the RFD, and it
grew closer to the ground, while precip was advancing across the
lake very slowly toward us. Rain was swirling around the funnel,
and very rapid downward cascading motion enveloped it, bringing
more rain around and obscuring our view. It dissappeared in the
rain for a bit, but things cleared away again to allow us to see
an S-shaped rope funnel much like the Gurnsey, WY tornado, but
ours had very poor contrast and was embedded in rain. We called
the NWS through a ham repeater superlink to report the tornado.
(At this time, Jamie and I were a couple miles south of Glenwood,
where we could see a nice wall cloud
to our northwest, probably what Bob was near. I got video of the
small tornado as it was roping out. I will get some stills made
from the video to post.)
We dropped east and south repeatedly to stay ahead of the updraft
base, but we never saw any more tornadoes. There were a few more
reports, but I think most of the tornadoes were brief and rain-wrapped.
We were occasionally out of position to see right into the notch,
but what we saw did not indicate large, well-lit tornadoes.
Scott and I grabbed a bite to eat at the Willmar Subway, then
set up east of town to get some video and stills of the lightning
after dark. The updraft was pretty well lit by intracloud lightning
and zits. It was a beautiful show. Later, after I drove back north
through the weakening and shrinking storm, the moon popped out
from behind what was left of the updraft base, and zits, anvil-crawlers,
and intracloud lightning lit up the downshear side of the updraft.
I tried getting out for stills/video, but the storm was drifting
north at me.
Overall, the storm was much grungier than what you'd think by
looking at radar. (Reflectivity) (Velocity)