The city of Genoa, Italy, nestled between the Tyrrhenian Sea and the Apennine Mountains, was rocked by severe flash foods on 4 November 2011. About 500 millimeters of raina third of the average annual rainfallfell in 6 hours, killing six people and devastating the city center. A storm of this intensity is considered to be a multicentennial-return-period event. The torrential rainfall inflicted the worst disaster Genoa has experienced since October 1970, when a similar event killed 25 people. The peculiar fine-scale properties of this event motivate a comprehensive research effort in the field of predictability of severe rainfall processes over areas of complex orography.