The showers and thunderstorms that pushed into western Iowa yesterday and made it to Des Moines was a bit unexpected. One of the main high resolution and short term forecast models run by NCEP/NWS is called HRRR. This model is run every hour producing a 15 hour forecast. The featured map presents the percentage of these runs (15 in total) that had simulated reflectivity above 30 dBz (stronger showers) for 6 PM yesterday evening. The inset map shows the actual RADAR data at that time. Only the last few model runs that afternoon picked up on the showers in west central Iowa and the coverage was under predicted.

Voting:
Good = 25
Bad = 8
Abstain = 5

Tags:   hrrr   forecast