July 10, 1996 Colorado Chase By Craig Setzer


Well, after several chases that turned up dry we hit pay dirt again.

On Tuesday, July 10, Al Pietrycha and I thought we'd play the Denver
Cyclone (see DCVZ, Szoke).  The cyclone was blowing the night before
at 04Z and I felt that it probably wouldn't move much.  By 16Z on
Tuesday the cyclone was about 30 NE of downtown DEN and just difting
slowly northeast.  We had plenty of moisture, almost too much but there
was some clearing working in from the foothills to the west and so
at noon we headed to the cyclone's center.  My feeling was that while
shear was not great, surface vorticity in the cyclone could be drawn
up if storms developed near the center.  They did around 1330 MDT and
for the next two and a half hours this one storm moved southward
along a shear zone right into DIA (Denver Intl Apt).  The first
rather large funnel probably reached the ground but the core cut our
view until we moved south.  Once we got back into better visibility,
we observed two landspout tornadoes to the south of the retreating
funnel just south of the core.  We observed a cyclic pattern of
dual landspouting and occassional meso-cyclonic tornadoing with a
total of nine tornadoes and two other funnels that probably did
tornado but we couldn't see ground contact.

The second meso-cyclonic tornado was on the ground for about 8
minutes south of the town of Hudson moving near homes and a farm.
The third was just north of DIA.  Additionally, a land-spout moved
over the south employee parking lot damaging as many as 30 cars.

The big stink now is that many of the workers at DIA were not
informed of the warning until 35 minutes had passed.  The terminal
and concourse were evacuated for a time and all flights stopped
for about twenty minutes.  While our depth perception was poor
do to the fairly low contrast environment, it looked like a few of
those planes flew fairly close to funnels/spouts.

Finally, we were amazed to see TWC was showing the worst of the
video we sent them.  We sent a clean copy of some pretty nice
shots and they edited it down to some poor choices.
Maybe they were pressed with the hurricane coming but the
pictures we shot were better than what was shown.

Craig Setzer
csetzer@rmi.net