NOAA Atlas 14 Precipitation Frequency Estimates in GIS Compatible Format
This web page provides access to NOAA Atlas 14 precipitation frequency estimates with upper and lower bounds of the 90% confidence interval
in GIS compatible format. For Volumes 2 and 3, only partial duration series (PDS)-based grids are available for download; annual maximum series (AMS)-based grids can be calculated by
applying ratios from Table 4.6.2 from corresponding NOAA Atlas 14 documents. For NOAA Atlas 14 Volume 1, and Volume 4 and above, both, AMS- and PDS-based grids are available for download.
Please note that the precipitation frequency estimates for each volume of NOAA Atlas 14 were computed independently using all available data at the time. Some discrepancies between
volumes at project boundaries are inevitable and they will generally be more pronounced for rarer frequencies.
DOWNLOAD GIS DATA:
To display and interpret the data, two separate files are needed:
File with zipped ASCII grids - This file contains the final, spatially interpolated, high-resolution NOAA Atlas 14 precipitation frequency estimates with confidence limits, and is the basis for the PFDS interface results.
The files either can be downloaded 1) via pull-down menu, 2) by anonymous ftp or 3) via web browser. Ftp is recommended for multiple-file downloads. To obtain precipitation frequency estimates without downloading files, please visit the PFDS interface.
1) Via pull-down menu:
2) By anonymous ftp:
Action
Type this
Open ftp to the server
ftp hdsc.nws.noaa.gov
Login as anonymous user
anonymous
Give the password
"your e-mail address"
Switch to binary mode
binary
Change directory
cd pub/hdsc/data/xx/ (replace "xx" with an abbreviation, abbreviations can be found at the top of the page in parenthesis, e.g. "ak" for Alaska)
Get one file
Example: mget ak100yr24ha.zip (this will download the 100-year 24-hour data for the Volume 7: Alaska)
Get several files
Example: mget ak*yr24ha.zip (the wildcard '*' in this case will get Alaska data for all frequencies for the 24-hour duration)
Quit ftp
quit
3) Via web browser:
alternatively you can peruse the ftp directory via a browser.