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9 gain an understanding which methods and guidelines are acceptable for meeting the state’s minimum criteria. Precipitation Frequency Events Since 2004, NOAA, National Weather Service (NWS), and HDSC have been working on updating and posting online precipitation frequency estimates, such as the 100-year event, as part of NOAA Atlas 14 for various parts of the United States. Funding is the largest impediment to the updating process, and is typically pooled from a variety of Federal, State, and local agencies. Figure 3 presents where NOAA Atlas 14 is currently available in blue. Figure 3: NOAA Atlas 14 Availability As of 2013, Colorado and Utah have been updated to NOAA Atlas 14, while Wyoming and Montana still use NOAA Atlas 2 for storm durations of 1-hour to 24- hours. In addition to NOAA Atlas 2, Montana also uses the USGS WRI Report 97-4004 “Regional Analysis of Annual Precipitation Maxima in Montana” (Parent, 1997). This document is used to produce large recurrence intervals for 2-, 6-, and 24-hour storm durations specifically for dam design purposes. The typical duration used for dam design is the 24-hour duration. While NOAA’s goal is to update all states to NOAA 14, as of this publication, no funding has been received by NOAA and no plans are currently in place for updating Montana and Wyoming to NOAA Atlas 14. The durations for NOAA Atlas 14 range from 5-minutes to 60 days and have an average recurrence interval ranging from 1 to 1,000 years. The updated analysis is different from NOAA Atlas 2 because it uses a longer period of record and a denser network of rain gauge stations, along with more robust and accepted statistical techniques. The precipitation magnitude- frequency relationships at individual rain gauge stations were based on regional frequency analysis approach based on L-moment statistics. The frequency analyses were carried out on annual maximum series (AMS) across a range of durations. Detailed information and discussion for deriving the estimates from rain gauge station data is provided in the NOAA Atlas 14 Document. The Precipitation Frequency Data Server (PFDS) is an online point-and-click interface developed to deliver NOAA Atlas 14 precipitation frequency estimates and associated information. Upon clicking a state on the map or selecting a state name from the drop-down menu, an interactive map of that state will be displayed. From there, a user can identify a location from the map or enter the latitude and longitude for which precipitation frequency estimates are needed. The PFDS is shown in Figure 4. Figure 4: Precipitation Frequency Data Server Estimates and their confidence intervals can be displayed directly as tables or graphs via separate tabs. Links to supplementary information (such as ASCII grids of estimates, associated temporal distributions of