In-Depth Weather: What is the ‘probability of precipitation’

ROCHESTER, N.Y. — It was a beneficial, soaking, and widespread rainfall on Monday for Western New York.

When you measure no more than a few drops of rain or a few sprinkles over the past three weeks, it is no surprise that our area has been considered very dry. Before Monday, we were in a drought scenario, at least in the lowest category. Officially the U.S. drought monitor has us listed in the “abnormally dry” category.

Going forward in time, what is the likelihood of getting more precipitation? And maybe, more importantly, how do we best convey that in a forecast? One way is by using what is called the “probability of precipitation.”

This forecast can range from zero percent chance to one hundred percent chance. But what does it actually mean in terms of a definition? Not to bore you, but it is the chance of getting precipitation in a specific timeframe and at a specific location. An example is what is the percent chance of rain for Monday night, at any one town in the seven-county area.

This can be very useful, especially during summer rain events. You can always find that information on the News 10NBC First Alert 10-day forecast at the top of each day. It is our way to help make plans for that upcoming picnic or golf game.