Two little phrases about the hill:
When Simonside puts on his cap, rain is sure to follow.
and
Simonside may lee, but Cartington Hill never.
(I suppose the latter means Simonside is sometimes alright weatherwise, but Cartington Hill is always appalling?! A better interpretation might be required.)
– mentioned in ‘Upper Coquetdale, Northumberland: its history, traditions, folk-lore and scenery’ by D D Dixon (1903).
Perhaps it means that sometimes you can out of the wind on Simonside, but never on Cartington Hill. It's an unusual use of the word "lee", presumably as an adjective rather than a noun.