When the snow fell in St. Louis last weekend, no one expected that it would impact NFL sports betting as much as it has. Been then again, no one expected the Metrodome to cave in.

The collapse of part of the ceiling of the St. Louis, Missouri Metrodome did more than just cause the pospontment and relocation of the Monday night Vikings vs Giants game to Tuesday in Detroit's Ford Field. It also raised the question of how sports betting sites and bookmakers handle such situations and gave them the opportunity to clarify some of those policies. Of course, the caveat to all of this, before going into the finer details, is that it is always up to the sportsbetting site or bookmaker how to handle any particular event, whether to cancel or honor betting, and although they generally try for a common sense approach, it is ultimately up to their own discretion.

That said, what most sports betting sites and bookmakers do in such instances, at least in so far as it has to do with team sports in the U.S., is to call it a "no action" anytime an event is not completed when it is scheduled to be. If a game is delayed for weather or other reasons, it usually doesn't result the bets being cancelled. The exception to this is if after they begin, they never reach completion, for whatever reason.

There are some common sense exceptions to this, of course. Such as if a baseball game running into extra innings doesn't finish until after midnight and therefore technically not on the same day.

So in the case of the Giants-Vikings game postponed because of the collapse of the Metrodome rooftop, the bets are considered "no action" and all wagers are refunded. Larger than that, however, is that the betting lines on a game could change overnight for any number of factors related to a postponement and relocation, including but not limited to a move from an indoor venue to an outdoor one.