Enhydris is a system for the storage and management of hydrological and meteorological time series. You can see it in action at http://openmeteo.org/.
The database is accessible through a web interface, which includes several data representation features such as tables, graphs and mapping capabilities. Data access is configurable to allow or to restrict user groups and/or privileged users to contribute or to download data. With these capabilities, Enhydris can be used either as a public repository of free data or as a private system for data storage. Time series can be downloaded in plain text format that can be directly loaded to Hydrognomon, a free tool for analysis and processing of meteorological time series.
Enhydris is written in Python/Django, and can be installed on every operating system on which Python runs, including GNU/Linux and Windows. It is free software, available under the GNU General Public License version 3 or any later version.
For more information about Enhydris, read its documentation in the doc directory or live at readthedocs.