A goal of this project is to build a digital dataset of pre-1948 hourly precipitation and make these data available through the Internet. A new digital dataset will be composed of at least two historical data sets and will be merged with a post-1948 dataset that is presently in digital format. New climatological studies and summaries may be developed from this new quality-assured long-term digital archive of hourly precipitation.


Dr. Richard L. Reinhardt

Desert Research Institute

2215 Raggio Parkway

Reno, NV 89512


(775) 674-7010

James A. Ashby, DRI, jawrcc@dri.edu

Michelle A. Chambers, DRI, mcwrcc@dri.edu



Dr. Michael J. Janis

Gloria Forthun, SERCC, forthun@dnr.sc.gov

Michael B. Johnson, SERCC, johnsonm@dnr.sc.gov

DATASET ONE: 1860-1941



Early in the data rescue program hourly precipitation data was discovered on more than 80 rolls of microfilm. These data were compiled under a WPA project in the 1940's. Data span the general period 1860-1941 with approximately 600 station records in the end of the period and only a few in the beginning of the period. Unfortunately, no film inventory is available. The 80 rolls of microfilm will be imaged and made available on-line.

The data were keyed as presented. Since the receipt of the keyed data from Image Entry, Inc, little work has been done to use these data. A rough inventory was produced but it is unknown how much data are hourly or how much are 6-hourly, 12-hourly, or daily. The quality of these data has not been determined.

Work to be accomplished:

The physical location of each station will be compared with the closest NWS Cooperative Weather Service station. If they are the same the coop number will be assigned to the HPD station; otherwise, a notation will be made so that an appropriate number can be assigned by NCDC.

The data will be converted to a standard TD3240 NCDC archive format.

Quality assurance procedures will be developed jointly. Each RCC team will apply the procedures. Work will be distributed in an equitable way that combines total number of sites and familiarity with the region.

Station history information will be compiled.

A thorough inventory by station and element will be compiled. This inventory will become part of the station history information.


DATASET TWO: 1930-1948


Hourly precipitation data from the 1930ís through 1948 was discovered in the NCDC library in a set of books known as the Hydrologic Bulletin. The books were also discovered on microfilm and it is this film that was imaged. Efforts are underway as of March 2003 to index these images so that they may be placed on-line via the WSSRD system. The exact number of stations available is not known.

Several tasks need to be accomplished in preparation for keying these data. Keying may begin as early as the winter of 2003 or as late as the summer of 2004.

Work to be accomplished: (This will be a 2 to 3 year effort.)

Year One:


Compile, as the images become available via WSSRD, a master station list including station name, state, and COOP station number.

Develop station history information.

Develop a keying format that reflects the primary format of the Hydrological Bulletins. Assess and test, with the keying contractor, the quality of the format and suggest changes to improve accuracy in the keying process where appropriate.

Year Two:

The data will be converted to a standard TD3240 NCDC archive format.

Develop and perform quality control procedures on the keyed data.


Begin researching methods to merge dataset one and data set two with the currently available TD3240 NCDC archived data set.

Identify duplicate entries between the datasets or missing records in the merged dataset. Explore options to rectify these scenarios.

Original analog (strip) charts from the 1800's through 1948 represent another source of hourly precipitation data. These charts are on microfilm and are available for imaging. Software to read these images and produce digital hourly values is being developed elsewhere. The quality of digitized data is unknown. Depending on the digitization effort, use of these data for filling in missing periods for key stations may be explored in year three.