How unusual are fire conditions ?

Extreme fire danger is expected in certain regions at summer times. However in some cases (e.g. Australian fire in 2019) possibly because of  early onsets or  prolonged conditions,  fires lead to catastrophic outcomes. These events are often referred as "anomalous" without a quantification. At the European Centre for Medium-Range Weather Forecasts (ECMWF), one tool that could aid pinpointing how uncommon these  situations  are  is the extreme forecast index (EFI), an index that highlights regions that are forecast to substantial diverege  from  to the local climate. 
The EFI concept has been in the past applied to meteorological fields such as temperature and precipitation. In this work we build on  previous findings by undertaking a global verification out to 15 days forecast  on the ability of the EFI for the Fire Weather Index (FWI)to capture extreme observed fire. Using the ECMWF ensemble prediction system and probabilistic skills score we analyse the fire season in  2019. In most case the  EFI is more skillful than the simple FWI to detect anomalous conditions for fire danger.

Following these results, the operational implementation of the FWI EFI  is currently being planned.