The prediction of fire danger conditions allows fire management agencies to implement fire prevention, detection and pre-suppression action plans before fire damages occur. However, in many countries fire danger rating relies on observed weather data, which only allows for daily environmental monitoring of fire conditions. Even when this estimation is enhanced with the combined use of satellite data, such as hot spots for early fire detection and land cover and fuel conditions, it normally only provides 4 to 6 h warnings. By using forecast conditions from advanced numerical weather models, early warning could be extended by up to 1–2 weeks, allowing for greater coordination of resource-sharing and mobilization within and across countries.
Using 1 year of pre-operational service in 2017 and the Fire Weather Index (FWI), in this talk we assess the capability of the system to predict fire danger globally and analyse in detail three major events in Chile, Portugal and California. The analysis shows that the skill provided by an ensemble forecast system extends to more than 10 days when compared to the use of mean climate, making a case for extending the forecast range to the sub-seasonal to seasonal timescale. However, accurate FWI prediction does not translate into accuracy in the forecast of fire activity globally. Indeed, when all fires detected in 2017 are considered, including agricultural- and human-induced burning, high FWI values only occur in 50 % of the cases and are limited to the Boreal regions. Nevertheless, for very large events which were driven by weather conditions, FWI forecasts provide advance warning that could be instrumental in setting up management and containment strategies.