Peak-flow frequency analyses for 99 selected streamgages in or near Montana, based on data through water year 2015 (ver. 1.1, August 2020)

The USGS Wyoming-Montana Water Science Center (WYMT WSC) recently completed a report documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgages operated by the WYMT WSC. In association with the report, this data release presents peak-flow frequency analyses for 99 selected streamgages that serve as examples showing various aspects of the WY-MT WSC frequency-analysis methods. The results are presented in three child items: a child item containing the results excel spreadsheet, a child item containing the peak flow specification file, and a child item containing the WATSTORE file.美国地质调查局（USGS）怀俄明-蒙大拿州水科学中心（WYMT WSC）近期完成一份报告，详述了落实《Bulletin 17C》指南后的洪峰流量频率分析方法。该方法可用于为WYMT WSC运营的选定流量测站，估算50%、42.9%、20%、10%、4%、2%、1%、0.5%及0.2%年超越概率（AEPs）对应的洪峰流量分位数。本次数据集发布配套上述报告，收录了99个选定流量测站的洪峰流量频率分析结果，这些测站作为示例，全面展示了WYMT WSC流量频率分析方法的各类应用场景。分析结果共分为三个子项：其一为存储分析结果的Excel电子表格，其二为洪峰流量规范文件，其三为WATSTORE文件。