In article ,
Robin Nicholson writes:
On Mon, 03 Jan 2005 17:57:45 +0000, Graham P Davis
wrote:


For the best chance of a decent Scandinavian High (not all of them give us
cold weather) a cold SST anomaly is needed in the Atlantic just to the
south of the Grand Banks.

Graham

Thanks for that! I am mildly surprised it is as simple as that!

I don't think that Graham intended to suggest that it was simple.

So the
next question is..what can cause the cold SST anomaly?
snip

The difficulty is, that whilst SST anomalies can affect the dominant
weather type, the converse is also true. So there are all sorts of
feedback loops that ideally should be taken into account. But the
attraction of SST anomalies as an aid to forecasting at the range of a
few months is that they do often persist on this sort of timescale,
because water is a lot slower to cool down or to warm up than is air. (I
have vague memories of "specific heat" from A-level Physics.)
--
John Hall "[It was] so steep that at intervals the street broke into steps,
like a person breaking into giggles or hiccups, and then resumed
its sober climb, until it had another fit of steps."
Ursula K Le Guin "The Beginning Place"