The cancellation of Wednesday's scheduled race in Bormio came after officials waited two hours while hoping for better weather conditions.
Officials said soft snow would have made skiing potentially unsafe.
Vonn, who was favored to extend her overall lead during the downhill final, holds a 157-point lead over Riesch, and is 178 points ahead of Hosp with 100 points at stake in each of three remaining races.
During World Cup Finals, all races must be held on the same day on which they are scheduled.
Megyn Kelly: Santa Claus and Jesus are both white men
Wisconsin business offering 'therapeutic cuddling' forced to close