In the weather world, you have long-range, medium-range and short-range forecast models. You also have control runs and ensemble runs. If you needed surgery for a medical condition, you would probably want a second, third or fourth opinion on your treatment options. In the weather forecasting world you want to look at the ensembles as they give you multiple opinions for the same run (with slightly different initialized inputs). Here are the latest SREF snowfall probabilities at the three main airports for tomorrow’s storm:
DC Storms 