1.5 Hour Lead Time from UAH CI Algorithm

Figure 1.
UAH CI forecast (red) valid from the 2040 UTC GOES imagery.

















Figure 2.
Radar valid at 2042 UTC.

















Figure 3.
Radar valid at 2209 UTC.

The UAH CI algorithm forecasted CI (first instance of 35+dBZ radar echo) approximately 1.5 hours before it was detected on radar for this case in western Minnesota (Figures 1 - 3, above). As subsequent GOES imagery rolled in, the algorithm continued to forecast CI down along a line of growing clouds to the south, achieving lead times of around 1 hour. According to the Storm Prediction Center storm reports (see Figure 4, below), this line of storms quickly turned severe and went on to produce several instances of large hail and even a tornado!


















Figure 4.
SPC storm reports for 05/10/2011, valid through ~12 UTC on 05/11/2011.