June 9, 2009
Storm Chase
Northwest Oklahoma
Editor: Putnam E. Reiter
Forecast/Setup -
Risk Area: Enhanced Moderate Risk
Initial Target Area: Caldwell, Kansas
SPC Products:
SWODY1
16:30z -
Local
Storm Reports
NAM 00z Initialization:
Surface Pressure
- Dewpoints -
CAPE
- MLCAPE
- CIN
- 0-3 Km Helicity -
Surface Temperature
-
850mb Dewpoints
- 850mb Vertical Velocity -
850mb Wind
-
700mb Wind
- 700mb Vertical
Velocity -
700mb Relative Humidity
- 500mb Temperature
- 500mb Wind
-
500mb Vertical
Velocity -
500mb Relative Humidify
- 500mb Vorticity -
250mb Wind
- 250mb Relative
Humidity -
18z Lamont -
00z Norman
Sounding
SPC Case Review
This year has been rather interesting and not in a
good way. After being quiet for severe weeks,
the atmosphere over Oklahoma appeared to be a little
more favorable for severe thunderstorms. For
this setup, good moisture return of upper 60s
dewpoints was in-place across the region.
Temperatures were expected to be in the upper 80s
resulting in CAPE values above 4000J/Kg. A
ridge has been in-place across Texas with the
southern jet stream over northern OK/southern KS.
The presence of stronger flow aloft and good
instability seemed to provide a good chance for
severe thunderstorms and tornadoes. Early in
the morning an MCS moved across eastern Kansas,
finally clearing the southeast parts of Kansas by
late afternoon. Several tornadoes were reported
with this activity.
An outflow boundary associated with the eastern
Kansas activity slowly moved south into southern
Kansas. This occurred as a warm front moved
north in Oklahoma, slowly becoming diffuse.
Daytime heating and convergence along these
boundaries was expected to result in severe
thunderstorm development. Directional and
speed shear were both adequate for organized severe
thunderstorms.
Storms developed during the late afternoon hours
near Dodge City, Kingfisher, and Elk Co KS.
Additional storms then developed near Ponca City and
Cherokee. CAPE values were rather low near
Ponca City to Wichita KS and east as the outflow
boundary pushed cool/dry air into the region.
Storms moving into this area quickly became elevated
and dissipated. Storm near Dodge City remained
isolated and supercellular the longest and produced
a brief tornado. Storm near Kingifsher became
part of a larger multi-cellular area. Storm
near Cherokee moved east and tried to stay isolated
but was unable to do so. It eventually started
propagating southeast and dissipated near Marland.
The only tornado of the afternoon in the chase area
was near Dodge City.
The Chase -
Team 1 - Rob Ferguson, Brett LaBar,
and Putnam Reiter
Miles Driven - 315 - Gas spent $34.00
Departure Time - 14:20 CDT
Return Time - 21:15 CDT
Track
We left Oklahoma City and went north on I-35. We got to
MM231 and went on north via HWY 177. We got to South Haven and went west
on HWY 81 and then turned north on HWY 49. We got about 10 miles north of
Caldwell and sat for a little bit. Getting data was a little tough but we
eventually got Edge service back. Mesonet showed veered winds near us and
just west. Additionally, while the CU development was pretty good near us
earlier it decreased over us and to the west.
We moved north to HWY 62 and east
into Wellington for a quick bite. During this
time several storms developed as a shortwave trof
moved into the region. We figured the storm
near Cherokee would be the best options given lack
of development near it and access to ample
instability. We headed back west on HWY 62 to
HWY 49 and then south through Caldwell. HWY 49
turns into HWY 81 at Caldwell so we end up on it and
head southwest. We had a good view of the
storm near Ponca City which had a wall cloud at this
time. It did a brief RFD, but nothing to
write home about.
We got into Medford just as our
storm was arriving. Its quick movement tended
to indicate it was slightly elevated. We had
some pea size hail and 45-50mph winds. We got
south of Medford around 18:30 and watched the storm.
The rotation area passed right over us, but it
wasn't anything that impressive. We could see
upward motion, but very little differential.
The storm go away from us as we
had to deal with bad road options, dirt versus
paved. We got back into Medford and started
following the storm. For something that was
going 30mph, it sure got away from us fast (hint I
think it was moving faster). We did see some
neat hail shafts and rainbows. Rob was also
playing with his new lightning trigger for his
camera. He managed to get an anvil strike with
a rainbow, not bad!
We continued on east via HWY 11
attempting to catch the storm. By this time it
was obvious the storm was headed (propogating)
southeast. So we got on I-35 and headed south
to get behind it and maybe look at some hail.
We got south of Tonkawa and saw the back-edge of the
storm. Seeing some upward motion and slight
differential, we decided to follow it a little more.
We had seen no hail of interest so far.
We exited to HWY 15 east, which
turned into HWY 156 towards Marland. Almost to
Marland we noticed the storm had become glaciated
and the updraft had disappeared. We believed
that this was the end of this storm. We sat
there and watch it, it has also slowed down.
The updraft area turned into a region of TCU and we
decided the fun was over. Heading back west on
HWY 156 to HWY 15 and then south on I-35.
Lessons
Learned -
- We had a good chase and adjusted well with the
changing conditions. I have no complaints about shifting our area as
the Cherokee storm took off. The only storm to produce a tornado was
near DDC and not sure I'd ended up there anyway.
- My only other note is the
over stating of wind speed as was noted in Medford.
A TV station called in 60jmph and I'd put money it
didn't get much above 50mph. We were there at
the same time and place an didn't get it.
Multimedia
-
Photo near
Nardin
(rainbow and CG) and then
Marland (decaying storm)
Oklahoma City RADAR
- WMV Format
Encounters
-
Engaged
Storm: Medford
Tornado: No
Funnel: No
Hail (larger than 0.75 inches): No
Wall Cloud: Yes and the one near Ponca City
Wind (above 57.4 mph): No
