Buffer lane
A lane kept deliberately empty in high winds, usually on an exposed bridge, so a vehicle blown sideways has somewhere to go instead of hitting traffic.
A buffer lane is an ordinary lane that has been closed on purpose while the wind is strong. Closing it leaves an empty strip between the traffic and the edge, so a high-sided lorry, caravan or trailer that gets pushed off course by a gust lands in empty space rather than into the side of another vehicle. When the wind drops it goes back to being a normal lane.
You will meet them where wind is funnelled or unobstructed: high-level bridges, exposed viaducts, elevated roads and open stretches of motorway. The rule for drivers is simple — do not drive in it. The only reasons to be in a buffer lane are that you were blown into it, or that you needed it to avoid a collision. Treating it as a free overtaking lane defeats the entire point of closing it.
In really severe wind the road authority goes further and closes the bridge altogether to high-sided vehicles, caravans and motorcycles, which is why the forecast is worth checking before you set off with a high load.
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