How much wind is too much?

Several years ago my wife and I were traveling with relatives with each of us pulling 27-28 ft. travel trailers to Grand Canyon with a serious cold front moving through the area. Even though I was pulling our trailer with an F250 I was constantly being pushed around by wind gusts. It was worse when you came out of a section of highway cut through a mountain. These are the ones with a wind sock mounted on the side of the road so you can see what the wind is doing. I don't know how high the gusts were but I was not enjoying the trip. When we stopped for refueling we discussed if should we continue. We decided to push on. A few miles after that we came upon a fifth wheel on it's side and a few more miles later a tractor trailer also on its side.
Anyway we made it ok but I decided I would never tow in those conditions again.

Dick