May 24, 2004
Storm Chase
West-Central Oklahoma
Editor:
Putnam E. Reiter
Forecast/Setup -
Risk Area: Slight Risk
Initial Target Area: Clinton, Oklahoma
Kind of a subtle setup for this
day. Models progged a longwave trough to develop over the west coast by
afternoon. This feature would have little to do with the setup over the
region. The best activity was expected in Kansas/Nebraska/Iowa where SPC
had a HIGH RISK in place. Temperatures across Oklahoma were quite warm,
which they have been much of May. Daytime max temperatures ended up in the
90s and when combined with dewpoints near 70 created a very unstable atmosphere.
CAPE values ended up above 3000 J/Kg and LIs below -8 across much of Oklahoma.
A strong cap (EML) was also in place with 780mb temperatures around +18C.
A dryline was arched from
northwest of Enid southwest to Altus. The surface low was in north-central
Kansas where the main activity was to occur. Across Oklahoma only a few
storms were expected due to the cap. However, the combination of strong
directional/speed shear along with the thermodynamics provided a favorable
environment for supercells. The cap was breach around 15:30 as a 300mb jet
max moved into the region.
Storms rapidly developed from
I-40 near Clinton southwest to Altus and on into Texas. While storms
attempted to form in northwest Oklahoma, the dryline bulge was across much of
this area. Hence the developing updrafts got too much dry air. No
organized convection initiated in northwest Oklahoma.
Four storms eventually
developed in southwest Oklahoma. Additionally, the storm that moved south
of Clinton split with the left mover moving north to near Weatherford. The
remaining supercell storms moved east-northeast across the region. At least
two of these produced tornadoes, one near Alfalfa and the other near Fredrick.
SPC Products: SWO
Day 1 Graphics:
Risk Area
-
Tornado Prob -
Damaging Wind Prob -
Hail Prob -
Storm Plot -
LSRs
Surface Maps:
Temperature
- Dewpoint -
Wind Speed -
CAPE -
LI
Soundings:
OUN
Mesoeta 00z Initialization:
Surface Pressure -
Convective Inhibition
-
0-1km Helicity
-
0-3km Helicity
-
850mb Temperatures
-
850mb Dewpoints
-
850mb Windspeed -
850mb Vertical Velocity
-
700mb
Wind -
700mb Temperatures
-
700mb Relative Humidity -
700mb Vertical
Velocity -
500mb Vertical Velocity -
500mb Temperature -
500mb
Vorticity -
500mb
Wind
-
250mb Wind
-
250mb Relative
Humidity
The Chase -
Team 1 - Rob Ferguson and
Putnam Reiter
Miles Driven - 180
Departure Time - 14:00
Return Time - 22:00
We left Oklahoma City and
headed out west on I-40. SPC issued a tornado watch for western Oklahoma.
We noted a lot of towering cumulus to the west along with developed anvils.
Getting RADAR support we exited at Highway 281 and went south towards Binger.
We got to Binger and turned west on Highway 152, trying to avoid the hail core
at this point. We turned south on Highway 146 to Albert. About this
time we got storm-scale features, including the updraft region. There
wasn't much to note at this point.
Getting south of Albert we
drove west on a county road to near Fort Cobb lake. We ended up sitting
just north of Forth Cobb lake and watched the storm move northeast. We saw
several funnels with the storm, but no tornadoes. We probably sat north of
Fort Cobb lake for about thirty minutes. As the storm started getting east
of us we took off north on a county road and then back into Albert. We
continued east out of Albert as it looked like the storm had gone a little south
of east. We turned north on a county line road that took us into Binger
and then went east on Highway 152. The storm had developed periodic wall
clouds but really didn't bring together a funnel. As we got east of Binger
we noticed that the storm had lost much of the updraft base features and it did
appear the base was rising. A little later information from the NWS
confirmed this observation. Along with this was another storm just
southwest of us. We figured that this storm had cutoff the inflow for our
storm. At first we circled back towards Binger on Highway 152, but decided
to drive south on Highway 281 a few miles and wait for the southern storm to
pass. As the storm got east of us we noticed that it was also in some
serious trouble. We drove into Gracemont where we got nickel sized hail.
Seeing that the storm was a goner we drove back north on Highway 281 to Highway
152 and then went east. We turned north on Highway 81 to I-40 and back
home. Both storms had dissipated by this time. The big storm of the
day was in southern Oklahoma near Fredrick which produced large hail and a brief
tornado.
Note: Our storm near
Alfalfa did indeed produce a tornado, which we noticed when watching the video.
Thanks to Ray Hardy for data support.
Lessons Learned -
- About the only main thing is
to watch the surface as well as the clouds for a tornado. As the video
shows we completely missed both tornadoes. Large temperature/dewpoint
spreads may result in a limited condensation funnel.
Multimedia -
- Video of
a tornado over Alfalfa, Oklahoma.
Clip 1 (5MB). Wall Cloud near
Eakly, Oklahoma.
Clip 2 (7MB).
- Still shot of a power flash,
indicative a tornado.
1
Encounters -
Engaged Storm: Alfalfa,
Oklahoma
Tornado: Yes
Funnel: Yes
Hail (larger than 0.75 inches): Nickel
Wall Cloud: Yes
Wind (above 57.4 mph): No
