Rain eases but does not end Switzerland’s forest fire danger

Rain in recent days has lowered forest fire danger levels in many Swiss cantons, but some areas remain at risk and absolute fire bans are still in force, SRF reports.

The federal danger map remained at the highest level for an unusually long time this autumn. Forest fire danger began rising in May, said Stefan Beyeler of the Federal Office for the Environment. While the levels are coordinated nationally, each canton decides which protective measures to impose.

Glarus has lifted its ban on fires near forests, while an absolute fire ban remains in force in parts of Graubünden. Local conditions matter as well as the calculated danger level, said Lukas Schuster, who coordinates forest fire measures in Graubünden. Authorities assess conditions on the ground rather than relying on forecasts, he said. Small amounts of rain may not pass through the tree canopy to the forest floor, leaving autumn leaves dry.

Since 2023, cantons have had access to a new programme for assessing forest fire danger. Boris Pezzatti of the Swiss Federal Institute for Forest, Snow and Landscape Research helped develop the model, called Nearest Fire Day. Its developers received extensive feedback during the hot summer, including on days when its calculations differed from local assessments. The information is being used to improve the model.

The Federal Office for the Environment provides cantons with two models. The Canadian Fire Weather Index requires various parameters to be entered manually. Nearest Fire Day generates an automatic recommendation and takes more local forest conditions into account, as well as information about past fires.

The federal office updates the danger levels and publishes them online. Beyeler said coordination with the cantons was working well and stressed the importance of informing the public. Switzerland had only smaller forest fires this summer.