A thunderstorm developed along a residual outflow boundary/stationary front southwest of San Angelo Wednesday afternoon.  The forecaster group issued an experimental severe thunderstorm warning based on lightning jump data, ProbSevere output, and all radar tilts examination.  Figure 1 below shows a loop of 0.5 degree KSJT reflectivity and ProbSevere contours.  ProbSevere first exceeded 50% at 1952 UTC, 60% at 2002 UTC, and 80% at 2012 UTC.  The experimental data along with all radar tilts analysis helped forecasters increase lead-time and confidence in issuing a severe thunderstorm warning.  After the warning was issued the storm again experienced a lightning jump and ProbSevere values maxed at 100%, with MRMS MESH over 3.00″.

-Sieglaff