How does CIMIS work?
Specific weather parameters are collected on site and temporarily stored in a data logger that is mounted on the mast of the weather stations. A computer at DWR headquarters in Sacramento calls every CIMIS station beginning around midnight (Pacific Standard Time) and retrieves the previous days data. The data is checked for quality and flagged, if necessary. Flagging does not mean the data is bad but as an indication of possible problems or deviations from expected normalcy. The flagging is explained in the quality control section of this web site. Reference Evapotranspiration (ETo) is calculated from this data and stored in a database along with the collected climatic data. Users can access the stored data via the Internet and/or FTP.
