Water Year to Date Percent of Normal (%)

<span style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>The 13 Weather Service (NWS) River Forecast Centers (RFC) produce Quantitative Precipitation Estimates (QPE) for their individual RFC areas. The RFCs produce the data using a multi-sensor approach utilizing NWS 88D radar estimates of precipitation, automated and manual precipitation gauges and satellite estimates of precipitation. These QPEs are used as input into their hydrologic models to produce NWS river forecasts and guidance products. The QPEs from each RFC are combined into a single mosaic to create a QPE product that covers the lower 48 states, Alaska and Puerto Rico. These QPE 's measuring units are in inches. The data are on an approximate 4km x 4km grid cell scale. </span><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>The individual hourly data products (labeled Since 12Z Observed and those labeled Last X hours) contain data for the labeled time frame. These products are updated every hour to incorporate the most recent data.</p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>The individual daily data products (Today's Analysis Observed, those labeled Last X Days Observed, and those labeled X To Date Observed.) represent a 24 hour total ending at 12UTC on the indicated date. These 24-hour data are then summed together to produce multi-day precipitation totals. Normal precipitation data are also produced for the Today's Analysis Observed and multi-day summations of 7 days or greater using data from the PRISM Climate Group. Percent of normal and departure from normal comparisons are also available by comparing the QPE data with the PRISM normal data. The daily data may be updated several times between 12UTC and 21UTC each day as updated data becomes available.</p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>Link to graphical web page: <a href='https://water.weather.gov/precip/index.php' rel='nofollow ugc'>https://water.weather.gov/precip/index.php</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>Link to data download (Advanced Hydrologic Predictive Services (AHPS) Precipitation Downloads): <a href='https://water.weather.gov/precip/download.php' rel='nofollow ugc'>https://water.weather.gov/precip/download.php</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>Links to metadata:</p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'><a href='https://water.weather.gov/precip/metadata/DailyObservedPrecip.xml' rel='nofollow ugc'>Observed</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'><a href='https://water.weather.gov/precip/metadata/NormalPrecip.xml' rel='nofollow ugc'>Normal</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'><a href='https://water.weather.gov/precip/metadata/DepartFromNormalPrecip.xml' rel='nofollow ugc'>Departure from Normal</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'><a href='https://water.weather.gov/precip/metadata/PercentOfNormalPrecip.xml' rel='nofollow ugc'>Percent of Normal Precipitation</a></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>Questions/Concerns about the service, please contact the <a href='mailto:[e-mail]' rel='nofollow ugc'>DISS GIS</a> team</p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'><span style='font-weight:bold;'>Time Information:</span></p><p style='color:rgb(0, 0, 0); font-family:Verdana, Arial, Helvetica, sans-serif; font-size:14.399999618530273px;'>This service is not time enabled</p>

13个美国国家气象局（National Weather Service, NWS）下属的河流预报中心（River Forecast Centers, RFC）会为各自负责的辖区生成定量降水估计（Quantitative Precipitation Estimation, QPE）产品。各河流预报中心采用多传感器融合方案生成该数据，具体融合了NWS 88D多普勒雷达降水反演结果、自动与人工雨量站观测数据以及卫星降水反演结果。上述定量降水估计产品将作为水文模型的输入数据，用于生成国家气象局的河流预报与指导产品。各河流预报中心生成的定量降水估计数据会被拼接为单张镶嵌图，形成覆盖美国本土48州、阿拉斯加州与波多黎各全域的QPE产品。该产品的降水量单位为英寸，数据采用近似4km×4km的网格单元尺度。

逐小时数据产品（标注为「自12Z观测以来」与「过去X小时」两类）包含对应标注时段的观测数据。此类产品每小时更新一次，以纳入最新观测数据。

单日数据产品包括「当日观测分析」「过去X天观测」及「当日至今观测」三类，其数据为以对应日期12世界协调时（UTC）为终止时刻的24小时累计降水量。随后可将多组24小时累计数据求和，得到多日累计降水量。针对「当日观测分析」以及7天及以上时长的多日累计降水量，可借助PRISM气候研究组的观测数据生成气候平均降水量数据。通过将QPE数据与PRISM气候平均数据进行比对，还可得到降水量距平百分率与距平值两类对比结果。每日12UTC至21UTC期间，若有更新观测数据可用，单日数据产品将进行多次更新。

可视化网页链接：https://water.weather.gov/precip/index.php

数据下载链接（高级水文预测服务（Advanced Hydrologic Predictive Services, AHPS）降水数据下载）：https://water.weather.gov/precip/download.php

元数据链接：
观测数据：https://water.weather.gov/precip/metadata/DailyObservedPrecip.xml
气候平均数据：https://water.weather.gov/precip/metadata/NormalPrecip.xml
降水量距平值：https://water.weather.gov/precip/metadata/DepartFromNormalPrecip.xml
降水量距平百分率：https://water.weather.gov/precip/metadata/PercentOfNormalPrecip.xml

若对该服务有疑问或建议，请联系DISS GIS团队

时间信息：本服务未启用时间维度功能