In article ,
Dave Cornwell writes:
I was wondering if such a stable block would/could have formed
Dec-Feb in the current times? No real reason not to but our recent
cold spells have had a lot of LP about them and perhaps this type
of block would have been less stable with the warmer seas then?

I think prolonged spells of blocking have always been much more common
in late winter through to spring than they are earlier in the winter.
When I say "always", I should perhaps qualify that as "at least since
about the middle of the 20th century and possibly earlier". I say that
because the exceptional number of Februaries since then with a sub-zero
CET (1947, 1956, 1963, 1986) indicate months where there was almost
certainly exceptionally prolonged blocking.
--
John Hall
"Madam, you have between your legs an instrument capable
of giving pleasure to thousands and all you can do is scratch it."
Sir Thomas Beecham (1879-1961) to a lady cellist