Experimental warning KCYS

A strong thunderstorm developed near Cheyenne, Wyoming late Tuesday afternoon.  The forecasters at EWP have grown more comfortable using the NOAA/CIMSS ProbSevere output and noticed at 2330 UTC 6 May 2014 the probabilities jumped to 66%.  The ProbSevere information combined with radar appearance caused the EWP forecaster to issue an experimental severe thunderstorm warning at 2331 UTC 6 May 2014 (Figure 1).

Figure 1. NOAA/CIMSS ProbSevere model, KCYS 0.5 degree reflectivity, and EWP experimental warnings valid 2330/2331 UTC 6 May 2014.

This storm proceeded to split and weaken for a time, but then began to reorganize.  The ProbSevere output again increased to 64% at 0010 UTC 7 May 2014 (Figure 2) and 74% at 0026 UTC 7 May 2014 (Figure 3).

Figure 2. NOAA/CIMSS ProbSevere and MRMS composite reflectivity at 0010 UTC 7 May 2014.

Figure 3.  NOAA/CIMSS ProbSevere and MRMS composite reflectivity at 0026 UTC 7 May 2014.

The Cheyenne NWS office issued a severe thunderstorm warning on this storm at 0030 UTC 7 May 2014.  Should any reports be received, we will post them here.

-Sieglaff