The Coldest Day of Winter

[chionomaniac]

St Hilary's Day -13th January has traditionally been heralded the coldest day of winter. This probably dates back to 1086 when a great frost started spreading over the country on St Hilary's Day. It lasted well into March and is said to be the severest Arctic spell the country has ever seen.

This year it looks far from likely that St Hilary's Day will be any where near cold looking at the charts:

850s

ground temps

Looking back over the last 50 years their may be a few times when St Hilary's day may have been one of the years coldest - the usual suspects!:

1963

1981

1987 (the coldest of the three)

However most years St Hilary's Day is mild with no noticeable cold. In fact one fairly recent year stands out- Ice creams all round!

1997

Does anyone know what statistically this country's coldest day actually is?

c

[eddie]

Very interesting post chionomaniac.

Using the CET records from the Hadley Centre:

/edit because I got it wrong first time...

If you take the average temperature for each day since 1772 then the coldest day is January 12th at 3.0C.

The coldest day in the period 1971-2000 is actually February 15th, also at 3.0C.

Edited January 7, 2008 by eddie

[chionomaniac]

Very interesting post chionomaniac.

Using the CET records from the Hadley Centre:

/edit because I got it wrong first time...

If you take the average temperature for each day since 1772 then the coldest day is January 12th at 3.0C.

The coldest day in the period 1971-2000 is actually February 15th, also at 3.0C.

It looks like there may have been a grain of truth originally then!

But in more recent times the coldest day is later in the year. I bet it won't be too long until it is in March!

c

[eddie]

I am guessing it's more to do with the sample size. 30 years is a small enough data set that one really cold or warm day can affect the average a lot.

Over the whole series from 1772 no February days are even in the top 20 coldest.

[Rustynailer]

I just had a google:

Hillary of Poiters AD300-367 (some say AD368) died Jan 13th. However his Saints day would have been on January the 3rd in AD1086 and the great frost. He was only given a Saints day by the Vatican in 1970: Jan 13th.

Which makes interesting reading with eddies post above

Am I right to speculate it (coldest day) was well into December at AD367/8 ?

Russ.

Sorry forgot to add that it was the Julien calender back in 1086 and 367/8

Edited January 7, 2008 by Rustynailer

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

What is the coldest single day since records began?

[chionomaniac]

What is the coldest single day since records began?

The coldest temp recorded in the UK is -27.2 °C at Braemar, Aberdeenshire, 10 January 1982 and 11 February 1895 and Altnaharra, Highland, 30 December 1995

I don't know what the lowest daytime maxima is. Anyone?

c

[Optimus Prime]

I don't know what the lowest daytime maxima is. Anyone?

c

Only the Metoffice would probably know that. Most likely it was the 12th January 1987 (although before the 1900s there were one or two similar low maximas) for England where maxima never rose above -8c in a few areas. That really was a remarkable spell.

As for the UK as a whole the lowest maxima ever recorded was on the 10th January 1982 at Braemar with an eye-opening Maxima of -19.1c.

[Marduk]

Only the Metoffice would probably know that. Most likely it was the 12th January 1987 (although before the 1900s there were one or two similar low maximas) for England where maxima never rose above -8c in a few areas. That really was a remarkable spell.

As for the UK as a whole the lowest maxima ever recorded was on the 10th January 1982 at Braemar with an eye-opening Maxima of -19.1c.

Seems that the whole Europe was taken by that extremely cold spell! Looked up that day for my region, and by that day the tmax was -19'c and two days earlier it was -25'c, can not imagine how cold that must have felt that day Most common is to see a tmax around -10'c here every year in a cold spell but it varietes a lot... :o

[Optimus Prime]

Would be interesting to know what sort of temperatures were recorded in this such cold spell;

I would have thought for some parts of Europe there may have been similar low maximum temperatures.