Quantitative Precip Estimate (QPE) / Quantitative Precip Forecast (QPF)/Return Frequency

This page displays APRFC's 24-hr precipitation estimate for the past 10 days (Day -10 to Yesterday) and the 24-hr precipitation forecast for the next 10 days (Today to Day 10) on the top row.  The bottom row displays the associated precipitation return frequency for that day.  Mouse-over a button to display the desired image below. 

For return frequency, values below 1 represent the ratio of precipitation vs the 1-year return frequency value. Values above 1 indicate the return frequency in years.  For example, if the value is 25, then the precipitation amount equals the 25-year return frequency.  (i.e. a 1 in 25 year event).  If the value is 0.5, then the precipitation amount is half of the 1-year return frequency.  Precipitation frequency values were obtained from the NOAA Atlas 14 dataset (https://hdsc.nws.noaa.gov).