Graham Easterling wrote:

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...udden-stratosp
heric- 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

The same thing happens in the west of Scotland.. Visibility just ahaed
of a warm front is, typically, much better even than in cold arctic
outbreaks.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr