The National Weather Service Hydrometeorological Design Studies Center has released NOAA Atlas 14, Volume 8. The Atlas provides precipitation frequency estimates for many of the Midwestern states, including Minnesota. Analyses of the historical frequency of heavy rainfall events are of importance to engineers and others involved in designing and operating infrastructure such as culverts and stormwater runoff ponds.
The information in NOAA Atlas 14, Volume 8 supersedes precipitation frequency estimates contained in these documents:
The new estimates are based on improvements in three primary areas: denser data networks with a greater period of record, the application of regional frequency analysis using L-moments for selecting and parameterizing probability distributions, and new techniques for spatial interpolation and mapping. See the documentation describing the station metadata, data, and project methodology used. Also, many questions are answered in the Frequently Asked Questions about NOAA Atlas 14 section of the National Weather Service Hydrometeorological Design Studies Center web site.
NOAA Atlas 14, Volume 8 was funded in part by the State of Minnesota, including funds provided from the Environment & Natural Resources Trust Fund.