May 26, 2008
Storm Chase
Western Oklahoma
Editor: Putnam E. Reiter
Forecast/Setup -
Risk Area: Moderate Risk
Initial Target Area: Gage, Oklahoma
SPC Products:
SWO -
LSR Plot
NAM 00z Initialization:
Surface Pressure
- Dewpoints -
CAPE
- MLCAPE
- CIN
- 0-3 Km Helicity -
Surface Temperature
- 850mb
Temperatures -
850mb Dewpoints
- 850mb Wind -
850mb Vertical
Velocity
- 700mb Wind
- 700mb
Temperatures -
700mb Relative Humidity
- 500mb Temperature
- 500mb Wind
-
500mb Relative Humidify
- 500mb Vorticity -
250mb Wind
- 250mb Relative
Humidity
Hook-Echo Discussions
- see the blog, sequence number is 2008-12-X
SPC Case Review
After a wild Memorial Weekend that we missed, we couldn't
pass up a "give me." Moisture was not a problem as no cold fronts had
passed through the region and temperatures were going to be in the upper 80s/low
90s. This was predicted to yield CAPE values in the 4000 J/Kg range.
The cap was expected to be a problem, but given that it was late May, we weren't
surprised. An upper system was progged just west of the area and this
would provide decent directional and speed shear aloft for organized severe
thunderstorms.
We picked northwest Oklahoma due to more favorable 500mb - 200mb flow.
Additionally, this was closer to the triple point. This seemed to be the
best area as a comprise between the thermodynamics to the south and the dynamics
over the region. Farther south into Oklahoma the mid level winds weakened
and while the degree of instability was favorable for organized storms, it would
be tough to get a supercell. The 12z NAM developed convection across
northwest Oklahoma during the late afternoon hours and also showed activity in
southwest Oklahoma. There was some discussion that this would mess thing
up, but I didn't bite into that thinking. There was a lot of moisture and
storms would have to go up along I-20 and stay there to interfere with the low
level moisture.
SPC issued a tornado watch during the early afternoon hours for parts of western
Oklahoma into the panhandle and southwest Kansas. Storms developed in
southwest Kansas all the way to the southern Texas panhandle. A storm also
developed in the northern Texas panhandle. The storms in northwest
Oklahoma did not amount to much while storms elsewhere formed into supercells,
including those near Wellington, Texas. Storms in Kansas, near Greensburg,
managed to produce tornadoes, but little other tornadic activity occurred.
The storms in southwest Oklahoma produced destructive hail.
The Chase -
Team 1 - Brett
LaBare, Rob Ferguson, and Putnam Reiter
Miles Driven - 530 - Gas spent $125
Departure Time - 12:00 CDT
Return Time - 00:30 CDT
We left Oklahoma City and headed to Gage. Rob had
recommended that location and since he needed affirmation that he's smarter than
he thinks he is, I decided to go along with it. We drove up HWY 3 through
Watonga and intended to take HWY 60 at Seiling and go west. However, we
missed our turn, so we kept going to Woodward. Getting into Woodward, we
filed up the tank and decided to drift west a few miles on HWY 15. Sitting
off the road we watched to the west and southwest. We didn't have to wait
long to see moist convection develop. As the updraft developed an anvil we
started south after it. We took HWY 15 to Tangier south. Reaching
Sharon-Shattuck RD we went west a few miles to N1895 RD south. We got to
HWY 60 and went east to Hammon. We watched the storm to our southwest and
noticed along with RADAR that the storm had split in two. The organization
wasn't that great, but we still decided to sit just east of Hammon and watch it.
We spent a good 30-45 minutes watching it, seeing some
attempts at a wall cloud, but I wouldn't say it ever really got one going.
As it got north of us, we took off to the east on HWY 60 and turned north on
2070 RD. As we got north the updraft became visible and it appeared the
base was rising. We watched it a few more minutes and the updraft area
continued to shrink. About this time we got RADAR back and noticed a
supercell near Wellington. Seeing that there wasn't that much going on in
our neck of the woods, we decided to head to the panhandle activity.
We took HWY 34 south to Elk City, watching RADAR the whole
way. I predicted we'd be in range around 18:00 and with the time of year,
storms would be easy to follow for a few more hours. We got to Elk City
and the original storm we went after had weakened and merged with another storm
to its west. However, a storm farther south, probably south of Wellington
was moving east towards southwest Oklahoma and this one had a tornado warning on
it. We got gas in Elk City and then jumped on I-40 west. As we got
to Sayre we saw a storm to our northwest with an updraft base. Hearing
reports of rotation, we decided to investigate, this was the original storm we
came south for or should I say what was left.
We exited on to Cemetery Road and went north about a mile.
We then turned back west on BKL road and watch it. As always when you're
10+ miles from a storm you see things that might not exist. As we got
closer to it, we noted the updraft base and attempts at a wall cloud. I
really felt the original activity back in the panhandle was better and had more
potential to interact with outflow boundaries from this activity.
Additionally, I thought there might have been some anvil interaction going on
between these storms. So, we took HWY 283 south through Elk City and
jumped on I-40 west. This seemed to take forever as I was watching the
storm in the panhandle move towards southwest Oklahoma and we needed to get
south in front of it.
We finally got to our exit and took HWY 30 south. I was
plotting our distance to HWY 9, our east option. It was about a 15 minute
drive, but a stressful 15 minutes. We get almost to HWY 9 and back off the
throttle some as the storm was still to our west and we were in the in-flow
notch. We watched the storm here and noticed some grass fires, most likely
started by lightning. As we sat there we watched a well defined wall
cloud, but opposing flow wasn't the best. It got closer and we decided to
drop south to HWY 9 and get east. As we did the RFD cutoff the circulation
center and it reformed near HWY 9. We sat at periodic spots on HWY 9 near
Vinson and Reed watching the storm. The storm had well defined wall clouds
with great upward motion, but differential motion was never that great.
There might have been funnel attempts with RFD cycles, but that was the main
thing. The most amazing thing was the lightning. CG's all around us,
it was amazing. Had anvil CG with 8 return strokes. I wish we had it
on tape as it was amazing. We watched the lightning start two more grass
fires, one of which required suppression.
We shifted east along HWY 9 as the storm moved east.
Eventually we noticed a northeast movement and decided to turn north just west
of Reed. We didn't make it very far when we got word of another storm
coming up from the southwest. So, we turned around and went back to HWY 9
and went west. We had a good view of the updraft region along with a wall
cloud. As with the prior storm it had great upward motion but differential
was lacking. I thought we might see some better activity due to boundary
interaction from the first storm. This storm behaved very much like the
first one as it moved east and then suddenly went northeast.
We stayed with it as dark approached but tried to go look at
some hail. We did managed to measure 2.50 inch hail with the first storm.
We didn't get to find any other hail, as we had to avoid the other hail cores.
We drove back east on HWY 9 intending to watch the storm but also start our trek
home. The storm wasn't doing anything all that great, but we stayed with
it for a while. We got to HWY 283 and went north a few miles and then back
east on HWY 9 into Granite. We stopped for a few minutes and then decided
to head on home. Finally getting to HWY 283, we headed north to I-40 and
then east to Oklahoma City.
Over all this was a great chase, just shy of getting a
tornado. Brett is still a tornado virgin, but we're working on that one.
He got to see a lot of storm structure and storm hazards. The latter was
clearly noted during our movements along HWY 9. When we got there we
didn't see any other cars. Slowly but surely the other chasers started to
arrive and the road got more crowded. That's when we noticed things going
downhill. Despite the frequent cloud to ground lightning activity, we
noted several chasers out of their vehicles video taping. One person even
had his tripod setup in the roadway. I do believe these were chasers and
not locals. It is unfortunate, but this is noted all over the Plains.
Despite what we saw, getting around wasn't that bad. Although, I still
have to train Brett how to throw the car in drive and punch the accelerator.
Maybe a few hours of NASCAR will do.
Lessons
Learned -
- This was about as perfect of a chase as we have
had. No issues that I can think of that we did wrong.
Multimedia
-
Enid - RADAR Loop -
3MB
Fredrick - RADAR Loop - 3MB
Webcam - 7.2MB -
Quicktime is required
Encounters
-
Engaged
Storm: East of Hammon
Tornado: No
Funnel: No
Hail (larger than 0.75 inches): Yes - Nickel
Wall Cloud: No
Wind (above 57.4 mph): No
Engaged
Storm: HWY 30 and HWY 9 - Near Vinson
Tornado: No
Funnel: Yes
Hail (larger than 0.75 inches): Yes - 2.50 Measured
Wall Cloud: Yes
Wind (above 57.4 mph): No
Engaged
Storm: West of Vinson
Tornado: No
Funnel: Yes
Hail (larger than 0.75 inches): No - We didn't get close enough.
Wall Cloud: Yes
Wind (above 57.4 mph): No
