The increase in the amount of available data from Volume 9 to Volume 14, both in the number of stations and their record lengths, could have a considerable effect on precipitation frequency estimates. For stations used in Volume 9, almost a decade of data has accumulated since the completion of the current estimates. Also, many stations that were not retained for analysis in Volume 9 due to short records will be considered for Volume 14.

The purpose of this project is to update precipitation frequency estimates for Louisiana that are published in NOAA Atlas 14 Volume 9. Like previous NOAA Atlas 14 volumes, the estimates and associated bounds of 90% confidence intervals will be provided at 30 arc-sec resolution for durations of 5-minute through 60-day at average recurrence intervals (ARIs) of 1-year through 1,000-year. The study results will be published as NOAA Atlas 14 Volume 14, a wholly web based publication available at Precipitation Frequency Data Server (PFDS). The publication will include the artifacts provided in previous NOAA Atlas 14 Volumes, including access through the PFDS, base grids in standard formats together with error estimates, electronic copies of maps, charts of seasonal distributions and probabilistic temporal distributions of heavy precipitation, and detailed documentation. Updated areal reduction factors, which are needed to calculate analogous areal precipitation frequency estimates, will not be developed as a part of this project.

The attached proposed Statement of Work by NOAA provides detailed information on the following: Task 1 - Data Collection and Quality Control Task 2 – Regionalization and calculation of regional statistics Task 3 - Frequency distribution selection and frequency calculations Task 4 - Estimates for 5-minute and 10-minute durations Task 5 - Internal consistency at observing locations Task 6 - Error estimates for DDF/IDF curves Task 7 - Spatial interpolation and consistency Task 8 - Temporal distributions Task 9 - Peer review Task 10 - Documentation Task 11 - Final deliverables Task 12 - Status Reporting

Multiple entities in Louisiana will contribute to this project, including: o Office of Community Development (lead agency; OCD) o Coastal Protection and Restoration Authority o Department of Transportation and Development o Office of Homeland Security and Emergency Preparedness o Department of Wildlife and Fisheries