That's easy, in one of the big storms in the late eighties I was driving a delivery van on a country A road (now a B road thanks to the M40). I came to an open stretch of road, the wind was blowing a constant 30 mph, probably gusting to over 70mph. As soon as I past the last big tree and bush the van I was driving went from being on six tyres (twin rear axle, 3.5 tonne, nearly empty) to two maybe two and half

I was being blown into oncoming traffic, most worrying a big HGV I could see coming down the road, not to mention cars and vans. I held it like this for what seemed like ages, it was probably no more than a few seconds but scary as hell. Somehow the road cleared of traffic just as the wind gusted and blew me onto the verge the other side of the road. I had missed all traffic and trees to land on grass, half in a ditch but nobody's perfect. My only injury a sprained thumb when the steering wheel was wrenched from my hand when the front wheels hit the curb. The bloke with me had a soft landing, he landed on me!! By pure luck there was a police car only a few cars behind, they said there was nothing I could have done.
Scary enough for you?