The rainfall episode that began on Saturday, October 3rd, 2026, and has been described as historic and exceptional in Catalunya, has affected various areas differently. In Sant Julià de Vilatorta and Vilalleons, in line with the general trend of the Osona region, the rain fell moderately, constantly, and in a regulated manner.
The episode started around 8:30 PM on Saturday the 3rd and continued uninterrupted until around 6:30 PM on Sunday the 4th. These nearly 22 hours of continuous but moderate precipitation allowed the soil to absorb the water progressively without causing significant problems to the local streams and ravines.
In contrast, the Montseny area exceeded 200 mm of rainfall. This caused a significant increase in the flow of the Riera Major, which in a few hours went from 0.1 m³/s to 4.5 m³/s. The river's level rose from just over 40 cm to 1.70 cm.
