Even F1, unless it turns into Sepang 2009 or Nürburgring 2007, no need for cancellation.
Need I remind people that every year when May comes around we see celebration of this:
Now I know times are different now, but it just seems wild that we celebrate these iconic events of the past while simultaneously raising alarms about organiser recklessness because an outdoor sport has to deal with the existence of weather.
Hell, even far more recently 2010's legendary Giro that received almost universal praise gave us all of the below, 100% of which would have likely been cancelled, abridged or neutralized today: