FOREST WEATHER. From June 1, 2023, the forest weather forecast will be able to prevent the risk of a fire starting for each French department. How does this tool work?
“72,000 hectares including 60,000 hectares of forests went up in smoke” during the year 2022 in France. A catastrophic assessment aggravated by the drought which should continue, and perhaps increase, for the summer of 2023. Unthinkable for the government to see again so many surfaces swept away by the flames and a prevention solution was presented on April 25 by the Minister of Ecological Transition Christophe Béchu: forest weather. Promised last October after the fires that had ravaged tens of thousands of hectares in Gironde, around the Mediterranean and even in Brittany, this new tool available from June 1 should make it possible to “prevent, anticipate and inform” about the risk of forest fires.
How will forest weather work?
Every day, from June 1, 2023 and at least until the end of September, the forest weather report will specify department by department the degree of fire risk. Thanks to a scale system and a well-known color code, the French will be able to know at a glance if their region is prone to fire outbreaks. Four alert levels are provided:
- Green: low risk when “forecast weather conditions and the latest precipitation mitigate the risk of starting and spreading forest fires”.
- Yellow: moderate risk
- Orange: high risk
- Red: very high risk “compared to summer normals”.
These alerts could be accompanied by certain preventive measures or messages to adopt behaviors adapted to the situation. “The hotter it is, the drier it is, the higher the risk of fire. We define risk thresholds, which are both in intensity and geographical coverage. [Le niveau d’alerte] must already be a first warning signal on the fact of taking the necessary precautions”, detailed Virginie Schwarz, the president and director general of Météo France at a press conference. Note that if an alert concerns an entire department , certain subtleties may be taken into account, specified the boss of the meteorological institute: “For example, when we are going to be in yellow, this means that overall in the department we are not going to have very unfavorable conditions, but that we may already have locally problematic or risky situations”.
How is the alert level defined?
Forest weather was born out of the collaboration between Météo France and the National Forestry Organization (ONF). Valid for two days, the forecasts published daily will be based on meteorological data such as temperature, wind strength or humidity associated with ONF observations on the dryness of vegetation and soils. They will make it possible to assess the propensity of the fire to start and spread.
Forest weather combined with other preventive measures
The forest weather forecast is intended to apply to the entire French territory, but locally other tools could be used to provide additional and more precise fire risk prevention. This is the case of the forest fire weather forecast already available to firefighters and authorities. This service, which currently concerns 15 departments, should extend to 34 territories this summer, then to 55 for the year 2024, anticipated Virginie Schwarz.
Finally, in addition to these maps provided by Météo France, the mayors will have access to satellite maps to delimit with more precision the areas at risk in their municipality, according to the details of BFM TV.