The Forecast Wars on Weather Twitter

What you expected from this past weekend’s winter storm likely depended on where you got your weather news. If you watched the Weather Channel or visited the National Weather Service web page, you’d have learned about the “increasing threat for accumulating snow” or “possible” freezing rain in your area, each report hedged with a modicum of uncertainty. Snow and rain can be difficult events to predict because long-range models shift from day to day, and sometimes from hour to hour, with general patterns of pressure, precipitation, air speed, and temperature fluctuating constantly in the run-up to a big storm. This is why professional meteorologists speak in potentialities and probabilities, identifying trends across many different models to determine the likelihood of a given outcome.