On Sat, 4 Jan 2014 21:36:46 +0000
John Hall wrote:

Sadly I don't think the measurements would be available for 1947, and
probably not for 1963 either.

I think we need to look down rather than up to find the reason for the
62-3 winter and this one.

The anomalous pressure distribution for the 62-3 winter was attributed
to favourable SST anomalies in the NE Pacific (Namias area) and the
Atlantic off the Grand Banks. In both areas the water was colder than
normal.

In winter, a cold Namias area is associated with lower than normal
pressure south of the Bering Strait and high between the pole and the
Canadian Archipelago. This set-up means that the coldest air will move
into Russia. Conversely, a warm Namias area, such as we have this year,
is associated with cooler than usual winters in the eastern two-thirds
of the USA.

Over Europe and the North Atlantic, a cold Namias area is associated
with high pressure centred near the Russo-Finnish border and low just
west of Ireland. The pressure anomalies associated with a cold pool
south of the Grand Banks are high over Iceland and low over the Azores.
It seems that, in 1962-3 the two sea areas being cold combined to
produce the harsh winter.

This year, as I said, the Namias area is warm and this is giving the
cold winter in NE America. Over this part of the world, one would
expect a high pressure anomaly centred just west of Ireland which
obviously hasn't happened. Although there is a warm pool south of the
Grand Banks, it's elongated W-E and a little further south than
necessary so the effect of this would be to increase zonality.

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