"Gavin Staples" wrote in message news:...
From my area of the UK, which is of course East Anglia. This is how I
would categorise a cold spell. This occurring in either December, January
or February, which of course are the 3 winter months.

1 out 10: 3 or 4 days consecutive, of north westerly winds and night
frosts of -2 to -3. Daytime maximums of between 4 and 5C. The occasional
light snow shower.

2 out 10: 3 or 4 days consecutive of north winds and night frosts of -3
to -4C. Daytime maximums of 3 to 4C. The occasional light snow shower,
perhaps a moderate one or two snow showers.

3 out of 10: 3 or 4 days of north winds and night frosts of -4C. Daytime
maximums of 1C to 2C. Snow showers, the occasional one settling lightly.

4 out of 10: 3 or 4 days of north easterly winds and night frosts of -4C.
More frequent snow showers and a daytime max of 1C perhaps one or two days
in that with maxs of 0C. Daytime frosts from this level onwards.

5 out of 10: 3 or 4 days of easterlies and night frosts of -4C with one or
two at -5C to -6C. Snow showers and snow settling to a depth of 2 inches.
Maximum temperatures on 2 days of 0C to -1C. Snow on the ground for 3 days

6 out 10: 4 to 6 days of north east or easterlies with night frosts -5C
to -6C. Snow showers and daytime maximums of 0C to -1C on 2 to 3 days.
Snow lying for 4 days.

7 out of 10: 6 to 7 days with east to north east winds, night frost -6C
to -8C. Snow showers and a longer period of snow giving a level depth of 3
inches and laying on the ground for 5 days. Daytime maximums 0C to -2C on
4 days out of that.

8 out of 10: 8 days to 10 days with east winds and north east winds.
Night frosts -8C to -10C. At least 1 -10C in that bunch. Snow on the
ground to a depth of 5 to 8 inches having fallen from a southerly track
depression in the English Channel. Further snow later on from snow
showers. At least 6 days with a max below -1C and 2 days with a max of -4C
to -5C. Snow on the ground in that for 10 days to 12 days.

9 out of 10: 12 days to 14 days with a cold spell from either north to
north east or easterly. Any combination will do. Snow on the ground at
least 6 inches deep. Night frosts -7C to -12C with at least 4 nights with
a -10C. At least 6 days with a max below 0C and out of those 3 with a max
below -4C. Snow on the ground for 14 days or more. December 1981 did this
and a bit more besides.

10 out of 10: More than 14 days with a cold spell from any very cold
combination. Snow on the ground for the whole of that time and preferably
longer. Snow depths of greater than 6 inches caused by southerly track
depressions and fronts. Night frosts down to below -15C on at least 3
nights. They do not have to be consecutive. At least 7 days in a row with
a max below 0C with 3 days with a max below -5C. January 1982 nearly hit
this, but it wasn't for 14 days though. January 1963 managed to do so. As
did January 1940.


Obviously there are variations in this. This is a guide for those living
in the South Midlands, East Anglia and Home counties as to what I would
regard as cold spell categorisation.




Just for the records. Snow lay on the ground in Cambridge for 70
consecutive days in 1962/63.




--
Gavin Staples.



Horseheath. Cambridge, UK. 93m ASL.

www.gavinstaples.com
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2006.

I'd categorise them pretty much the same for everywhere bar upland
areas and the far SW: Here's how I'd rate cold/snowy snaps I remember
using your scale:

9 or 10- never seen one
8- January 1987
7- January and February 1985, February 1991, December 1996-January 1997
6- 19-23 December 1995
5- February 1994 (twice, 14-16th and 22-24th), late January 1996

There have been other cold snaps just as notable but which don't fit
that categorisation well, usually because the wind was the wrong
direction, there was not enough snow, the snow didn't lie for enough
days etc. For example the last week of December 1995 was nearly as cold
as January 1987 but had little snow (the 19-20th was the main snow
event here that month), December 1990 had one of the biggest snowfalls
I can remember yet it wasn't an easterly and only remained for 3 days;
December 2000 had a couple of very cold nights yet the cold spell was
short with only a dusting of snow.

Edmund