The Helm Wind is a named
wind
Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few ho ...
in
Cumbria
Cumbria ( ) is a ceremonial and non-metropolitan county in North West England, bordering Scotland. The county and Cumbria County Council, its local government, came into existence in 1974 after the passage of the Local Government Act 1972. C ...
,
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...
, a strong north-easterly wind which blows down the south-west slope of the
Cross Fell
Cross Fell is the highest mountain in the Pennines of Northern England and the highest point in England outside the Lake District. It is located in the North Pennines Area of Outstanding Natural Beauty. It lies within the county of Cumbria and ...
escarpment. It is the only named wind in the
British Isles
The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...
, although many other mountain regions in Britain exhibit the same phenomenon when the weather conditions are favourable. It may take its name from the
helmet
A helmet is a form of protective gear worn to protect the head. More specifically, a helmet complements the skull in protecting the human brain. Ceremonial or symbolic helmets (e.g., a policeman's helmet in the United Kingdom) without protect ...
or
cap
A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. Caps typically have a visor, or no brim at all. They are popular in casual and informal se ...
of
cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may ...
which forms above Cross Fell, known as the Helm Bar, since a
line of clouds over the fells can predict and accompany a Helm. Research into the helm wind was carried out by
Gordon Manley
Gordon Valentine Manley, FRGS (3 January 1902 – 29 January 1980) was a British climatologist who has been described as "probably the best known, most prolific and most expert on the climate of Britain of his generation". He assembled the Centra ...
in the 1930s. He interpreted the phenomenon in hydrodynamic terms as a "
standing wave" and "rotor", a model confirmed in 1939 by glider flights.
The
dale at the head of the Eden Valley has its own Helm Wind, which sweeps over
Mallerstang
Mallerstang is a civil parish in the extreme east of Cumbria, and, geographically, a dale at the head of the upper Eden Valley. Originally part of Westmorland, it lies about south of the nearest town, Kirkby Stephen. Its eastern edge, at Aisg ...
Edge, particularly affecting the central part of the dale.
This can be similarly fierce and can blow for two days or more, sometimes sounding like an express train. As with the wind at Cross Fell, its arrival is accompanied by the formation of a dense cap of cloud (a "Helm Bar") which, in this case, forms along the high ground on the eastern side of the dale.
References
{{Reflist
External links
Example of a Helm Bar taken from near Appleby in Westmorland on April 3rd 2007on a website that specialises in "wind of the world".
Climate of England
Föhn effect
Geography of Cumbria
Winds
Pennines
pl:Wiatr#Lokalne wiatry nazwane