May 3, 2003
Storm Chase
SW Oklahoma/NW Texas
Editor:
Putnam E. Reiter
Forecast/Setup -
Risk Area: Slight Risk
Initial Target Area: Altus, Oklahoma
The mid-level pattern was
characterized by a shortwave ridge over southern Texas and an approaching
shortwave trof from the SW U.S. During the day little in the way of energy
was expected to move across the region. However, a combination of surface
heating and moisture return was expected to be sufficient for severe
thunderstorms.
A strong cap was in place
across the region with convective temperatures around 92F. A surface low
formed in eastern Colorado. The dryline move to just east of I-27 or from
Amarillo to Lubbock on south by afternoon. A warm front quickly moved
north from south Texas to southern Oklahoma by afternoon. A triple point
was located near Plainville, Texas.
The shortwave ridge was progged
to move east during the day and allow for deep convection. Additionally
the mid-level wind fields were progged to increase with a 500mb jet max moving
into parts of the region. While many of these things did come together,
only one storm was able to develop a tornado. This storm was intercepted
by many people, which wasn't too difficult given that it was moving 20 mph.
While this was technically a
tornado day, it wasn't what we were forecasting. The cap, cirrus clouds,
and mid-level ridging all combined to reduce the threat this day. However,
the threat was realized on Sunday with a historic outbreak across
Kansas/Missouri/Arkansas.
SPC Products:
SWO Day 1 Graphics:
Risk Area
-
Tornado Prob -
Damaging Wind Prob -
Hail Prob
Surface Maps:
Temperature
- Dewpoint -
Wind Speed -
CAPE -
LI
GFS 00z Initialization:
Surface Pressure -
Surface Temperature -
Precipitable Water -
850mb Wind -
700mb Temperature
-
700mb
Wind -
500mb
Vorticity -
500mb
Wind -
300mb Wind
-
250mb Wind
The Chase -
Team 1 - David Underwood,
Sarah Davis, Ray Hardy, and Putnam Reiter
Miles Driven - 425
Departure Time - 12:30 CDT
Return Time - 22:00 CDT
We left Oklahoma City and
headed south on I-44. After a brief stop at KSWO-TV to decide our final
location. So, we headed west on Highway 62 to Altus. Getting there
around 16:00 CDT, we filled up and sat around for a while. Storms develop
about 30 miles east of the dryline in the Texas panhandle. One such split
started just northeast of Lubbock. The left mover headed towards Paducah
and Vernon, Texas. So, we went towards El Dorado and took Highway 6 south
to Quanah. We then went west about six miles on F.M. 104. Sitting
there, we watched the storm approach. It was rapidly decreasing as it
moved north-northeast at 50mph.
We followed it north-northeast
into southwest Oklahoma. Another storm had developed near Memphis, Texas,
and moved east into southwest Oklahoma. As we followed the Quanah storm
into Oklahoma we played tag with it near El Dorado, then Duke. Our storm
moved right in front of the Memphis storm, cutting off its inflow. We got
to the storm about the time the first one cut it off. There we got to a
view an ever increasing base, a sign of decay. Our storm mean while took
off to the north-northeast and ended up in northwest Oklahoma in about 90
minutes.
We headed home around 19:00
CDT, stopping by Altus for a quick break.
During part of this the right
mover produced a tornado in Haskell County. Several people got this
tornado and apparently it was quite impressive. Chasing it would have been
very easy since the storm was moving 20mph. It is something we should have
gone after, but then the warm front would have gone up if we did that.
Long live Murphy!
Lessons Learned -
- Left movers are not the
best storms to chase. Very few of them live long enough to do much.
May 3, 1999, was an example of a left mover from a split near Altus, surviving
for several hours. In this case, our storm didn't do much more that
produce very large hail.
Multimedia -
None
Encounters -
Engaged Storm: Yes - 7
miles west of Quanah, Texas
Tornado: No
Funnel: No
Hail (larger than 0.75 inches): No
Wall Cloud: Brief
Wind (above 57.4 mph): No
