Celebration of Snow will be after Marvel Super Hero Takeover. Marvel Super Hero lasts 2 weeks. That means the party ends on 9th May. 1 or 2 weeks later, the Celebration of Snow starts and lasts for a week. If you count both parties, they would both end at 30th May. In June, there will most likely be a Ultimate Jam and alter an Adventure Party: Temple of Fruit. If an party goes before Ultimate Jam and one before Adventure Party, the Fair will be most likely cancelled.
Note: I am not saying there will be a fair, adventure party or ultimate jam, this is just a theory!