Daymet: Daily Surface Weather Data and Climatological Summaries

The data distributed through this web site are generated from the Daymet model and have broad applications over a wide variety of scientific and research fields including hydrology, terrestrial vegetation growth models, carbon cycle science, and regional to large scale climate change analysis. Developed by Dr. Peter E Thornton to fulfill the need for daily climatological data necessary for plant growth model inputs, Daymet generates daily, gridded surfaces of temperature, precipitation, humidity, and radiation over large regions and takes into account areas of complex terrain.

Daymet data has been updated for 1980-2008 and expanded to include the United States, Mexico, and Canada (south of 52 degrees North) as station density allows. Data can be downloaded for a single 1-km x 1-km pixel as a text file of daily data for all Daymet variables, or as a gridded tile of daily data for each Daymet variable. Annual climatological summaries are also available for some Daymet variables.

This version of Daymet has been supported by NASA through the Modeling and Synthesis Thematic Data Center, a unit of the North American Carbon Program. The ground-based meteorological station data required for running Daymet have been acquired through the National Climatic Data Center, the National Resource Conservation Service, and additional datasets obtained through the generosity of the Mexican and Canadian Governments.