Fishing Bridge Wyoming Trip Feedback Please

Average Weather For Yellowstone National Park

The correct answer is apparently June 20 to September 7.

Remember what they say about averages: "You can still drown crossing a stream whose average depth is only 6 inches."

Better question is the odds on an eruption.

Wesernparkowner is correct. Freezing weather is -possible- any time of year in Yellowstone, I have seen it snow every month of the year.
July and August are least likely, which is also why the park is packed with tourists then.
Personally I prefer early and late also.

WoodGlue wrote:
May 10 - Sept 22 are the days of operation. You're not likely to freeze during these dates.

WoodGlue

Actually, overnight freezing temps should be expected up until about June 1st and after about September 10th. What you won't generally get is a deep freeze during the open dates, but it is not a sure thing. With very few precautions (unhooking and draining your water hose, keeping any plants inside) a rig should have no problem with a few hours of temps in the upper 20s. Personally, the benefits of an early or late stay in Yellowstone would far outweigh any concerns about cold temps.

May 10 - Sept 22 are the days of operation. You're not likely to freeze during these dates.

WoodGlue