In article ,
Col writes:

"John Hall" wrote in message
.. .
In article
,
Tudor Hughes writes:
On Jan 4, 12:04 pm, James Brown wrote:

And, er, remind me, when did the '47 Winter begin?...;-)- Hide quoted
text -

February. I was 4, but dont't remember it. The same could be
said of 1956, which I do remember, and 1986, which I remember even
better. I can't quite see what you're getting at. Surely these
events, whether or not significant, can occur at any time of the
winter?

Actually the 1947 winter began on about 23th January. But I'm sure
you're right that such events can occur at any time of year. (Though
there were an unusual number of really cold Februaries from the 1940s
onwards: 1947, 1956, 1963 and 1986 all had sub-zero CETs.)

And as late as Jan 18th 1947 the set-up appears to have been
mild and zonal.

Yes, there's a chart from mid-January 1947 in Gordon Manley's "Climate
and the British Scene" (illustrating a transient ridge of high pressure
IIRC) where one would have thought that there was no prospect of really
cold weather in the next couple of weeks. If the modern computer models
had been around then, I wonder how well they would have fared.

Out of interest, I looked up the values from the daily CET series that
Parker, Legg and Folland published in 1992. For the second half of
January 1947 they were (presumably max+min/2):

16th: 10.0
17th: 6.9
18th: 6.3
19th: 2.8
20th: 1.6
21st: 1.8
22nd: 1.0
23rd: 0.1
24th: -0.6
25th: -0.1
26th: -1.3
27th: -1.5
28th: -2.0
29th: -6.4
30th: -5.1
31st: -2.5

It's well-known that blocking seems to be more common in the second half
of the winter than in the second half, enough for the average February
rainfall to be substantially less than December's and January's, even
taking into account that February is a shorter month. I wonder if that
might indicate that mid to late January is a favoured time for SSW?
--
John Hall

"Whenever people agree with me I always feel I must be wrong."
Oscar Wilde