This image presents the precipitation - rain or snow - detected by weather radars. Red regions indicate heavy precipitation and bluish regions indicate slight precipitation.
The composite consists of radar echoes from Sweden, Norway, Denmark, Estonia and Finland. The images are part of the cooperation project between the above mentioned meteorological institutes, the Nordic weather radar network project (NORDRAD).
The light blue echoes can be result of coastlines, swarms of insects or cold sea. Rainfall rates in Finland and radar measurement with better filtering are available on page Rain and cloudiness.