Johannes Kühn once actually did that. In Oberhof, in fact.
Legendary race with Ebs winning his leg and Belgium leading for half of the race. We will see the same today with gusts of 65-85 km/h. It's going to be pretty wild. There will be also rain today. It's not a good day for relays. Not at all. But yeah...in the end it's all about the party.
Is there any reason they can't just push both events back a day?
In order to still award the medals, the relays and or mass starts could be retrospectively evaluated in the World Cup afterwards. The next relay races are scheduled for March 11 in Östersund, Sweden. Instead of competing for World Cup points, the athletes would then be competing for World Cup medals.
If I remember correctly, the Worlds in 1999 were postponed several time due to the cold weather in Kontiolahti. They only could do Sprint, Pursuit and Relays in Finland. Individual and Mass Start were held in Oslo one month later.