April 7, 2008
Storm Chase
Southwest
Oklahoma/Northwest Texas
Editor: Putnam E. Reiter
Forecast/Setup -
Risk Area: Slight Risk
Initial Target Area: Lawton, Oklahoma
A strong cold front moved through the
region a few days before this event, so moisture return was questionable.
However, time of year and presence of strong flow aloft, indicated there was
potential for severe weather. Unfortunately it wasn't as good as thought.
The setup had a developing trof in the
western U.S. that was to move eastward into the region. The timing was off
and as noted moisture wasn't that good. Moisture did rapidly increase
during the day with common upper 50s dewpoints and a few areas of low 60s.
The warm front ended up in central Oklahoma with a dryline in SW OK/NW Texas
when storms developed.
The warm front was of interest given that
it was a good boundary, but the dryline showed potential. CAPE values were
around 2500 J/Kg and LIs to -7 across parts of SW OK/NW TX. Winds aloft
were quite favorable for rotating updrafts and organized severe thunderstorms.
The timing of the event seemed well-timed as all the models showed development
during the afternoon hours.
Storms developed on cue around 16:00 and
SPC already had a PDS tornado watch up for the area. Additionally, they
upgraded the slight risk to a moderate. At first a cluster of storms
developed in NW Texas, but eventually a single supercell emerged. This
storm moved east near Electra and produced a tornado. Other storms tried
to develop, but failed to do so. The Electra storm continued east and
about the time it reach I-44, north of Wichita Falls, it died.
Other storms developed farther south in NW
Texas, with these storms primarily producing large hail. The warm front
had moved to north Central Oklahoma where several supercells developed along
this boundary and moved into northeast Oklahoma.
SPC Products:
SWO
Day 1
Graphics:
Risk Area
-
Tornado
Prob -
Damaging Wind Prob -
Hail Prob -
Storm Plot
- LSRs
- MCD's
Misc Products:
Area Weather Updates
Sounding:
None
NAM 00z Initialization:
Surface Pressure
- Dewpoints -
CAPE
- CIN -
0-3km Helicity -
Surface Temperature
- 850mb
Temperatures -
850mb Dewpoints
- 850mb Wind -
850mb Relative Humidity
- 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 2008-8-X
SPC Case Review
The Chase -
Team 1 - David
Underwood, Rob Ferguson, and Putnam Reiter
Miles Driven - 275
Departure Time - 15:00 CDT
Return Time - 20:00 CDT
We left Oklahoma City and headed south on I-44 towards Lawton,
our original target. We sat in Lawton as the storm by Electra developed
and organized into a supercell. We could tell that the Weather Service was
interested in this storm. However, we thought a storm was developing near
Davidson and decided to go look at it. So, we left our area just north of
Lawton and drove south on I-44 to HWY 62 and then went west. As we got
west of Lawton we noticed the storm near Davidson was gone, so we decided that
the one in Texas might be the better bet. However, at this point we
couldn't easily get there.
So, we turned south on Deyo Mission RD from Deyo and hooked up
on HWY 36 south through Faxon to Grandfield and turned west on HWY 70. As
we got close to Davison, we saw the area of development just to our north.
We also noticed that the storm in NW Texas wasn't doing as good. So, we
went north on HWY 183 to Fredrick and then east on HWY 5 to get a better
look at the storms near Cache. We drove back to HWY 36 and went north to
just past Faxon. We stopped there for about 20 minutes and decided to
continue on east.
The storms in Oklahoma were not doing very well and by this
time the storm in Texas was about gone. Two other storms had developed in NW TX
and looked impressive on RADAR. We hit I-44 and head back north.
Drove through some rain north of Lawton and that was about it. We kept on
going north to home.
Lessons
Learned -
- Forecasting: It wasn't the best day in the world,
but worth going out on. Moisture was the real issue, but it happens in
April. It would have been better with the upper system closer.
- Positioning: This isn't something to complain about, but could
have gone to Texas. Many other people stayed in Oklahoma and the Texas
storm did its thing pretty fast.
Multimedia
-
None
Fredrick, OK - RADAR Loop -
Webcam - 2.6 MB - Requires
Quick Time Player
Encounters
-
None
