On Saturday, December 29, 2018 at 7:18:14 PM UTC, John Hall wrote:
In message ,
Graham Easterling writes
On Saturday, December 29, 2018 at 5:28:39 PM UTC, Keith Harris wrote:
My daughter texted me after reading something in the paper and I
could give a balanced answer as to what effect this may or may not
have on our weather and why, but what I couldn't answer was what
causes this warming to occur. Doing a quick search and I couldn't find
the answer?

Is there a simple answer to this question?

Keith (Southend)

A bit here, but it's pretty superficial, more or less stating what
happens rather than why IMHO.
https://blog.metoffice.gov.uk/2013/0...stratospheric-
warming-ssw/
The blaming it on a large high, could easily be reversed, blaming the
large high on SSW.

I was looking for something rather more depth but couldn't find
anything, so I'd be interested as well.

Graham
Penzance

Presumably it must be known what causes it, as the computer models
picked up on it well in advance. So if it's being modelled, it must be
reasonably well understood.
--
John Hall
"Hegel was right when he said that we learn from history
that man can never learn anything from history."
George Bernard Shaw (1856-1950)

Not necessarily. Ahead of a warm front the visibility commonly becomes very good, high cloud streams in etc. It is therefore possible to forecast the likelyhood of rain followed by mizzle (certainly in Cornwall). The sequence is known without any need for an understanding of the mechanisms involved. Traditionally farmers fisherman etc. would forecast based purely on observations of the weather and an knowledge of the sequence of events.

In fact, because the main time Scilly is visible from Cornwall is ahead of an approaching warm front, there is a local sayng that "If you can see Scilly it's going to rain".

It would be good to have a detailed explanation of the evolution of a SSW event. At present it seems like a well kept secret (at least from me!) or it's rather predictable but little understood.

Graham
Penzance