UV forecast

The UV-Index

The UV Index describes the expected daily peak level of the erythemally weighted UV irradiance at ground level. The higher the UV Index, the higher the UV irradiance and the faster a sunburn can occur when skin is not protected. Sun protection measures have to be taken according to the UV index.

UV index forecasts for the ten forecast areas in Germany are issued every 3 days each year from April to September by BfS, in cooperation with the Federal Environment Agency, Germany's National Meteorological Service and other associated institutions. The forecasts are based on the previous measurement data of the UV monitoring network and actual meteorological data provided by the DWD.

The intensity of the UV radiation depends on the cloud coverage. If the cloud coverage decreased contrary to the weather forecast the predicted UV index would be too low. Therefore two UV index values are indicated if cloudiness is predicted. The lower value applies for the predicted cloudiness, the higher one for bright sunshine.