AbstractIn recent years, there has been a growing interest by different user communities to use radar-based rainfall products for identifying and quantifying heavy precipitation and other related information. A potentially viable product for such analyses is the National Weather Service (NWS) Stage IV Quantitative Precipitation Estimate (QPE), which covers the entire conterminous United States and is available at 1, 6, and 24 h temporal resolutions. The current article focuses on data artifacts in the Stage IV product over its full record period (2002–2013) and assesses their impacts on the analysis and derivation of heavy rainfall statistics. Examining annual maximum series extracted from the Stage IV 1-h accumulation product revealed the presence of numerous artifacts that were mostly linked to erroneous rain gauge reports and which can be mistaken as rainfall maxima. Artifacts were found over many parts of the United States, including the west, south, southeast, and northeast. Other erroneous features ...