The development of tools for flash flood forecasting. The introduction of spatial variability in TOPMODEL.

The aim of this work is to improve the flash flood forecasting (particularly on the Ardeche catchment). There are three main parts. The first one deals with the implementation, in a real time context, of an hydrometeorological forecasting system. The consequences, on discharge simulations, of the uncertainty on average rainfall evaluation (thanks to the raingauge network) are also quantified. The second part of the report concerns the increasing of discharge forecasting terms (until 12 hours, by using a stochastic generator of hourly rainfall scenarios, which was improved in order to integrate other information (qualitative or quantitative) about future rainfalls. At last, we tried to integrate the spatial variability of the rainfall in TOPMODEL: an entirely new version was developed, in order to understand the eventual influence of this spatial variability for the discharge generation.