What is AccuPOP?
AccuPOP is the AccuWeather Probability of Precipitation, which tells you the percentage chance that a measurable
amount of precipitation (at least 0.01" of rain and ice or 0.1" of snow) will fall at a specific location during
a specific time period.
Why is AccuPOP useful?
AccuWeather's revolutionary AccuPOP is the first multi-period 3-hour probability of precipitation and has
been created in response to The American Meteorological Society's 2002 statement endorsing probability
forecasts and recommending their use to be substantially increased. As a public service, AccuWeather is making available the AccuPOP for any precipitation, rain, snow, and ice for every location in the US, to cover the next 96 hours (4days). AccuPOP can be used as a tool in making plans for outdoor activities.
How do I Interpret AccuPop?
AccuPOP is shown graphically for each of 4 time periods: the next 3 hours, the next 6 hours,
the next 12 hours, and the next 24 hours. AccuPOP can range from 0% to 100%. A low AccuPOP means that there is a
small chance of measurable precipitation and does not indicate how light or heavy the precipitation may be.
So, along with the AccuPOP, we show the most probable amount of precipitation during each period.
Because each of the 4 AccuPOP time periods starts with the current hour, a high probability of precipitation
in the next few hours carries over into all the longer periods.
For example, if the AccuPOP in the next 3 hours is 90%, then the AccuPOP
in the next 24 hours will be at least 90, even if there is no chance of precipitation after the first 3 hours of the period.
In order to give you a better picture of when precipitation will occur, we also show a graph with the AccuPOP for each three hour period
in the next 24 hours.
How is AccuPOP created?
AccuPOP is created from The AccuWeather Forecast Engine using proprietary computer algorithms that determine the
probability of precipitation for each three-hour period based upon a combination of longer-term probabilities and
precipitation amounts.