2. Weather observations and forecasts

This section looks at the various meteorological observation and forecasting tools, and more particularly those dedicated to precipitation, a major factor in the genesis of flash floods. In meteorology, we distinguish between different spatial scales: the synoptic scale (several hundred kilometers), which focuses on general atmospheric circulation; the mesoscale (between several kilometers and several hundred kilometers), from which we can track thunderstorms and convective complexes; and the microscale, that of clouds (a few kilometers and below). Observation and forecasting of flash floods tend to fall into the latter two categories.