forecaster. The age-old question “What does this forecast mean to me?” is especially applicable to
Quantitative Precipitation Forecasts (QPF), as the forecast units are a vague concept that don’t easily
relate to the user. Climatology adds another potential source for confusion, as an inch of rain can lead to
drastically different consequences depending location and precipitation duration.
NOAA’s Atlas 14 dataset can aid in forecasting and communicating high-impact precipitation events.
Atlas 14 is an extensive catalog of precipitation frequency estimates across much of the Continental
United States, and NOAA provides these datasets in Geographic Information System (GIS) format.
Combining QPF with precipitation frequency estimates yields a Return Interval Forecast, which
calibrates the traditional precipitation forecast based on precipitation duration and climatology. In this
presentation, we take a look at several examples of this experimental product, discuss the potential for
an Impacts Catalog based on Return Interval Forecasts, and share a few instances where the product has
helped clarify our forecast message with core partners.