Qualitative Precip Estimate (QPE) / Qualitative Precip Forecast (QPF)/Return Frequency
This page displays APRFC's 24-hr precipitation estimate for the past 7 days (Day -7 to Yesterday) and the 24-hr precipitation forecast for the next 7 days (Today to Day 7) on the top row. The bottom row displays the associated precipitation return frequency for that day. The loop animates the forecasted 6-hr return frequency. 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).
Note: During the winter months, day 1 QPE graphics (Yesterday) are initially auto-populated with Multi-Sensor Multi-Radar (MRMS) data, then updated with the RFC's quality controlled data by late morning. QPE on weekends and holidays during the winter contains only MRMS data and is not updated with RFC data.