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Flood Frequency Data and 2020 Observed Flood Probability for Selected Streamgages in the Fortymile River Basin, Alaska, 1911-2020

March 24, 2022

This data release provides the source data and results of a flood frequency analysis and annual exceedance probability estimation for a flood that occurred on June 22, 2020 in the Fortymile River Basin, Alaska. Data are provided for two streamgages that had at least 10 years of peak-flow record. The data include streamgage information, PeakFQ input (.txt and .PSF files) PeakFQ output (.PRT, .EXP, and .JPEG files), flood frequency parameters, flood frequency estimates for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities, and annual exceedance probability estimates for the flood of interest. These data were intended to support investigations of streamflow in the Fortymile River Basin.