We talked about Monday evening weather in Montana and how the forecasts went.

NMM had a high false alarm rate but was the only model to correctly predict the severe storm in ID. ARW missed the storm by 200km to the southeast. Another comparison we always make here at the HWT is the 0Z vs the 12Z runs of thhe NMM. For this day, I think the 12Z NMM was much better than the 0Z. Steve thought it was “somewhat” better. The 12Z run had less false alarms in central MT and captured the ID storm area better.

The probability matched mean is an interesting way of summarizing the ensemble of forecasts. It has the spread of the ensemble, but the sharpness of an individual run. I’m not sure but I was told to check out Ebert/McBride for a reference on this.

The Monday forecast was pretty insignificant, so we also talked about the high-end derecho on Friday May 8. There were some differences between the 1 and 4-km CAPS solutions of this event. (I forget what they were).

David Ahijevych