PRISM Climate Data
1991-2020 Normals
We expect to begin releasing the 1991-2020 normals (including new solar normals) sometime in early December 2021. The best way to keep up-to-date on these developments is to subscribe to the PRISM-Updates mailing list.

Phasing Out ASCII Grid Format
Now that virtually everyone downloads PRISM data in BIL format, we will stop producing data in ASCII Grid format as of January 1, 2022. The 1991-2020 30-year normals will remain available in both formats, but the time series grids will be available in BIL format only. Note that if you have a particular need for it, the BIL grids can be converted to ASCII Grid format using the open source GDAL raster processing software. Notice updated 2021-10-28

The PRISM Climate Group gathers climate observations from a wide range of monitoring networks, applies sophisticated quality control measures, and develops spatial climate datasets to reveal short- and long-term climate patterns. The resulting datasets incorporate a variety of modeling techniques and are available at multiple spatial/temporal resolutions, covering the period from 1895 to the present. Whenever possible, we offer these datasets to the public, either free of charge or for a fee (depending on dataset size/complexity and funding available for the activity).


High-Resolution Data Available
The native grid resolution of the PRISM datasets is 800m, but they have been filtered to 4km resolution for easier downloading and manipulation on this website. The 800m versions of all PRISM datasets, which contain 25x more information, are available to users for a fee. Details on availability, pricing, and ordering are found here.

30-Year Normals: At the end of each decade, average values for temperature and precipitation are computed over the preceding 30 years. The current set of 30-year normals covers the period 1981-2010.

Comparisons: Maps showing how observed values have been deviating from long-term conditions (also known as anomalies) - includes the new Drought Indicator tool.

This Month: Although still very preliminary, results based on daily data readings are available for the month-in-progress.

Prior 6 Months: Provisional results based on both monthly and daily data are available for the 6 most recently completed months.

Recent Years: Daily and monthly observations become stabilized after 6 months. At that point the time series datasets are posted in this section, along with annual values computed at the end of each year.

Historical Past: Values prior to 1981 are based on less extensive observations. Time series datasets computed using monthly modeling are available for the years 1895-1990.

Projects: Map images and data prepared for outside agencies but now released for public use. Includes USDA Plant Hardiness Zone Maps, climate data for areas outside the continental U.S., and map images for individual states.

Data Explorer: analyze and download time-series data for a single location.

FAQ: Answers to frequently asked questions

This website is supported by the USDA Risk Management Agency