April 20, 2002

Storm Chase

Southwest Oklahoma

Editor:  Putnam Reiter

Forecast/Setup -

Risk Area:  Enhanced Moderate Risk
Initial Target Area:  Southwest Oklahoma

Arctic air mass was situated in Oklahoma and predicted by all models to move north during the day as a warm front.  Shortwave trof was to move into the region during the afternoon, with a rather impressive jet structure.  Surface low and associated surface features formed in the Texas panhandle.

The Chase -

Team 1 - Rob Ferguson and Putnam Reiter
Miles Driven - 200
Departure Time - 14:00 CDT
Return Time - 21:00 CDT

We drove to Lawton, Oklahoma, and then west to Snyder.  There we observed a classic warm front structure as southerly flow was battling the arctic air mass.  Some activity developed on top of us and quickly moved northeast in the strong mid-level flow.  This prompted a tornado watch from SPC.

Seeing that Snyder was a little too far north, we moved south to Fredrick.  Unfortunately a thick cirrus shield was across the area and the arctic air was not being eroded.  It actually started to advance southward during the day.  Clearing started to move across the region with some CU developing in our area.  The temperature was still in the mid 60's and little became of this attempt.  Eventually all the vertical motion stopped.  We packed up and headed home.

A storm formed in far western Texas, north of of Lubbock.  This storm moved northeast and quickly encountered the warm front.  It dissipated as fast as it developed.  There was neither an LSR nor warning anywhere in the moderate risk/tornado watch area.

Lessons Learned -

Standard problem with forecasting.  This one caught a lot of people off guard.  The SPC Day 1 at 13:00z was the best indication that this was going to be an off day.  SPC did a good job, tough forecasting day.

Encounters -

Engaged Storm:  No
Tornado:  No
Funnel:  No
Hail (larger than 0.75 inches):  No
Wall Cloud:  No
Wind (above 57.4 mph):  No