If you are going to get hit with high speed winds. and if you know the direction they will be coming from and you have the option.. Choose your parking angle.
now the OP said "Fairly flat land" So i'm guessing no major trees to flatten it or anyting.
Your two strongest aspects are either headed into the wind (you regularly enjoy 60-100 MPH equivalent winds just going down the road. And .. The reverse of that position (Tail on) depending on your RV (mine has no rear window so that's the way Id rather take a high wind)
Have parked and slept in 100 MPH plus gusts.
Got great gas millage that day.. There was chatter of a 14mpg Motor home.. Well, that day I averaged 13.8 with a 100 mph dead astern tail wind. I mean the tumble weeds were going straight down the road and passing me ilke I was in PARK.
And no, I do not recommend you try that.