It depends on if it's open country as mentioned earlier, or whether it's a head/tail wind vs a cross wind, and the difference between the sustained speed and gusts. Around here in the Twin Cities, it's sheltered enough so I'll go out with gusts up to 50. Anything more than that usually indicates a storm of some sort, and I've been out in a couple too many of those. On a North Dakota ride, we had head/cross winds once of 35 gusting to 55, which would blow us into the oncoming lane. Fortunately, the road was parallel I94 so there was no traffic. The last twelve miles took me two hours in my granny gear. If it'd been a busy road, I'd have sagged.