On the Road With Chuck and Vickie Doswell
Finally, a (multiple) Supercell day
Great low level flow into Nebraska
and South Dakota. We decided initially to play
the backed flow in the extreme portion of south-central South
The 500 mb pattern features at least
marginally favorable flow.
Low level shear was very favorable
in central Nebraska and South Dakota
Note narrow tongue of CAPE....we played
the northern portion of that.
Favorable low-level shear showed up
in the forecast SREH fields.
Actually, CAPE was probably higher
than forecast. Here is the dewpoint field.
300 mb flow was marginally unfavorable,
suggesting that the area would be in the "CAPE" robbing
front right quadrant of a jet streak. Turned out that there was
not much forcing at all.
While mid level winds looked weak,
the low level shear was favorable.
We adjusted our target south when the
surface low dropped southeastward faster than progged. As we drove
into Nebraska again we could see the northwest flank of supercell
We were approaching this southeastward
moving supercell from the northwest side flank.
Now we are a lot closer, still approaching
the storm from the northwest.
The rain free base tried to form a wall cloud.
This animation shows that the storms
all merged into a southward moving complex. No wonder we were
racing southward the entire time.
Finally got around the southside of
the first storm and it formed a blocky wall cloud.....
And nice inflow, laminar bands.....but
the road and a gas stop allowed us to get behind the hail core
for this storm and we lost it.
But to the north of the first storm
were storms number 2 and number 3. You can see the lovely rainfree
base with storm 2....and this storm had good rotational features.
Several tornado warnings were issued on that storm as we watched
it move towards us, but we did NOT see any tornadoes---perhaps
a brief funnel cloud as shown in the next image.
We have a feeling that these lowerings
might have been misidentified as funnels or tornadoes leading
to the warnings. Though the storm was lovely, and we stayed with
it well after sunset, we saw no tornadoes.
You can see the anvil from storm 3
to the north.