A number of storm events over France in 2019 and as recently as Storm Gloria over Spain in January, 2020 have been used to enhance FFI calculations within HydroMaster.
The improved Flash Flood Index is much more reactive to precipitation. More accurate results provide early warning for risk of overland flow, or before surface runoff reaches streams and in-situ monitoring devices. (Additional updates to HydroMaster include better data visualization of river systems now.)
The higher level of sensitivity was well tested by the destructive Storm Gloria. With notably high winds and heavy rainfall, the Mediterranean storm set several new meteorological records in Spain -- in terms of total rainfall, rainfall intensity, wave heights, heaviest recorded snowfall, and lightning strikes.
Causing widespread flooding, mudslides and storm surges across Spain and southern France, Storm Gloria has been saved to the storm events database for future analysis and comparison.
Since FFI finetuning has already become effective, the nowcast period – for the next one to three hours – reflects more sensitivity.
Basically, the Flash Flood Index can now serve as an early warning system as FFI coincides well with areas where subsequently increased risk of river bed flooding is expected to occur.