Gridded United States Daily Precipitation and Snowfall Time Series

U.S. Gridded Precipitation and Snowfall Time Series is digital data set DSI-3721, archived at the National Centers for Environmental Information (NCEI; formerly the National Climatic Data Center, NCDC). Geographic coverage is the 48 contiguous states of the United States of America. As stated, the data is gridded; each grid is 0.5 degrees of latitude and longitude. The data set consists of precipitation data and separate snowfall data. The precipitation data covers about 96 percent of the land area of the 48 states, and 100 percent of the area east of -105.0 longitude. Snowfall data covers about 95 percent of the land area. The time period is January 1, 1948 to December 31, 1999. Extensive additional information about the origin and the time of the observation of each precipitation/snowfall datum is included in the data set.