I can't give you a direct answer. But I can tell you we pulled into an open park in IA a few years ago in very strong winds. It was ~April and no one was in the park, just a bunch of open spots facing a wind blown field and lake. It was late and we needed to stop. I left the 5th wheel hooked up for stability and pointed the truck into the wind. We left the slides in and road out the night, a little bit nervous as it rocked and rolled. Next day heard there were tornados about 50miles away. Not sure what winds we had, but didn't enjoy it and more importantly were safe.
If you have to, maximize your odds: stay hooked up, put down stab jacks, and point into wind if you can...your trailer survives 60+ mph winds head-on every time you drive.