Helm wind
A fierce, cold, northeasterly wind that blows down the western escarpment of Cross Fell in Cumbria — the highest point of the Pennines. It is England's only named wind. The Helm arrives with a distinctive formation: a bank of cloud, called the Helm, caps the summit like a helmet, and a parallel roll of cloud, called the Helm Bar, forms in the valley below. Between the two, the wind roars downslope with a violence that can knock people off their feet and strip tiles from roofs. It has been documented since at least the 17th century and remains incompletely understood.
Etymology
From the Old English or Norse word for "helmet" — the cap of cloud that sits on the fell when the wind blows. The cloud is the helmet; the wind is what comes out from under it.
Notes
The only named wind in England. Macfarlane territory.
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