British Weather Extremes
EXTREMES//MINIMUM TEMPERATURES

Minimum Temperatures

Overview

Severe winter cold spells in Britain are associated with:
  • the advection of very cold air masses from the east or north
  • the subsequent establishment of a deep and extensive snow cover.
The advection of very cold air is most effective when Continental arctic air (from north-west Russia) reaches central and southern parts of England and Wales on an easterly wind, thus crossing a relatively narrow stretch of the North Sea. Widespread low daytime temperatures occur in such circumstances, especially over snow covered ground. An especially severe 'cold wave' occurred in January 1987 when, on the 12th, daytime maximum temperatures at low altitudes ranged from around 0°C in the Outer Hebrides to -8°C at several places in eastern England; Southend in Essex, where 38 cm. of snow was lying, did not exceed -9°C between 9 a.m. and 6 p.m.

Snow and ice surfaces reflect incoming radiation (the albedo effect) and thus suppress daytime maxima. However the most pronounced "feedback" of snow cover is on overnight temperatures, through radiative cooling, since snow is an extremely poor conductor of heat, especially when freshly fallen and dry. In January 1982 the record minimum temperature for England, -26.1°C was recorded when skies cleared immediately following a deep powdery snowfall.

Altnaharra weather stationThe met enclosure at Altnaharra, Sutherland (Credit: Dan Holley)
Very cold continental airstreams affecting Scotland are subject to greater warming as they approach over longer stretches of sea. There is therefore little difference between the absolute winter minima recorded in the Scottish Grampians and the English Midlands, despite the longer hours of winter darkness further north. However temperatures below -20°C are recorded much more frequently in Scotland. This is attributable to the higher altitude of much of the country and the more frequent incursions of air masses from Greenland and the colder parts of the North Atlantic; both these factors contribute to a higher frequency and extent of snow cover in Scotland.

Details of the lowest recorded temperature for each British County have been published in Journal of Meteorology, 8(83), pp. 269-272. Braemar, in the Eastern Grampians, has not only twice recorded the national record of -27.2°C but also logged Britain's annual 'low' in 43 of the 109 years between 1875 and 1983 (Journal of Meteorology, 9(85), pp. 3-5). Other "favoured" locations for low temperatures are highlighted by the table of daily 'lows', from October to May, published in Journal of Meteorology, 10(96), pp.45-51.

At maritime locations, where there is a small diurnal range of temperature, low temperatures are entirely related to rapid advection on strong easterly winds. The Scilly Isles, Britain's mildest winter outpost, did not escape the extreme cold wave of January 1987. Temperatures on the islands plunged to -7.3°C and Tresco gardens sustained disastrous losses of tender trees and shrubs.

Feeble mid-winter sunshine makes little impression on areas of intense stagnant cold which have developed over snow-covered ground under clear anticyclonic conditions. Consequently some of the coldest days have also occurred in such situations including the astonishing day maximum of -19°C at Braemar on 10th January 1982 (Journal of Meteorology, 7(66), pp. 34-37). Maxima of -8°C to -12°C were recorded at several places in the English Midlands during the cold spells of December 1981 and January 1982, especially where patches of freezing fog lingered.

In the absence of snow cover many of the most severe frosts during the summer half year are recorded over light sandy soils which are also a very poor conductor of heat. Outstanding examples include the record low May and June values recorded in the Breckland of Norfolk. Other locations experiencing low summer temperatures are within deeply sheltered upland valleys e.g. in the Grampians, the Southern Uplands and in Mid Wales, where sharp local cooling of polar air masses can occur. Long dry spells in spring and early summer contribute towards late frosts by reducing the heat retention properties of the soil. At all times of the year the lowest overnight temperatures can be expected in relatively dry air masses.


Lowest recorded temperatures for each month of the year, 1875 to 1990

Month °C °F Location Region Date
January -27.2 -17.0 Braemar Grampian 10 January 1982
-26.8 -16.2 Grantown on Spey Highland 8 January 1982
-26.7 -16.0 Kelso Borders 17 January 1881
-26.6 -15.9 Bowhill Borders 11 January 1982
-26.3 -15.3 Braemar Grampian 11 January 1982
-26.2 -15.2 West Linton Borders 11 January 1982
-26.1 -15.0 Newport Shropshire 10 January 1982
February -27.2 -17.0 Braemar Grampian 11 February 1895
-25.6 -14.0 Braemar Grampian 10 February 1895
-25.0 -13.0 Aviemore Highland 8 February 1895
-25.0 -13.0 Braemar Grampian 23 February 1955
March -22.8 -9.0 Logie Coldstone Grampian 14 March 1958
-22.2 -.80 Granton on Spey Highland 12 March 1958
-21.7 -7.0 Corwen Clwyd 3 March 1965
-21.7 -7.0 Kinbrace Highland 3 March 2001
-21.1 -6.0 Houghall Durham 4 March 1947
-21.1 -6.0 Peebles Borders 4 March 1947
-21.1 -6.0 Braemar Grampian 4 March 1947
-21.1 -6.0 Braemar Grampian 8 March 1947
April -15.0 5.0 Newton Rigg Cumbria 2 April 1917
14.4 6.0 Eskdalemuir Dumfries and Galloway 2 April 1917
-13.3 8.0 Braemar Grampian 11 April 1917
-12.8 9.0 Garforth West Yorkshire 24 April 1908
-12.8 9.0 Perth Tayside 24 April 1908
May -9.4 15.0 Lynford Norfolk 4 May 1941
-9.4 15.0 Lynford Norfolk 11 May 1941
-9.4 15.0 Fort Augustus Highland 15 May 1941
-8.9 16.0 Braemar Grampian 1 May 1927
June -5.6 22.0 Dalwhinnie Highland 9 June 1955
-5.6 22.0 Santon Downham Norfolk 1 June 1962
-5.6 22.0 Santon Downham Norfolk 3 June 1962
July -2.5 27.5 Lagganlia Highland 15 July 1977
-2.5 27.5 St Harmon Powys 9 July 1986
August -4.5 23.9 Lagganlia Highland 21 August 1973
-4.4 24.1 Grantown on Spey Highland 21 August 1973
-3.3 26.0 Inverdruie Highland 21 August 1973
-3.4 25.9 Kinbrace Highland 25 August 1986
September -6.7 20.0 Dalwhinnie Highland 26 September 1942
-6.2 20.8 Lagganlia Highland 27September 1975
-6.1 21.0 Glenlivet 23 September 1948
-6.1 21.0 Dalwhinnie Highland 15 September 1979
-6.0 21.2 Braemar Grampian 28 September 1974
-5.6 22.0 Santon Downham Norfolk 30 September 1969
October -11.7 11.0 Dalwhinnie Highland 28 October 1948
-11.4 11.4 Braemar Grampian 20 October 1880
November -23.3 -10.0 Braemar Grampian 14 November 1919
-22.8 -9.0 Braemar Grampian 15 November 1919
-21.7 -7.0 Perth Tayside 14 November 1919
-21.1 -6.0 West Linton Borders 14 November 1919
-21.1 -6.0 Balmoral Grampian 14 November 1919
-20.9 -5.6 Kinbrace Highland 30 November 1985
December -27.2 -17.0 Altnaharra Highland 30 December 1995
-26.7 -16.0 Kelso Borders 3 December 1879
-25.1 -13.4 Shawbury Shropshire 13 December 1981
-24.9 -12.8 Grantown-on-Spey Highland 30 December 1995
-24.6 -12.3 Aviemore Highland 30 December 1995