The 1962/1963 winter as observed at Belstead Hall (Suffolk) and through investigation of the synoptic charts

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1 The 1962/1963 winter as observed at Belstead Hall (Suffolk) and through investigation of the synoptic charts 18 James Dent Independent Consultant, Hadleigh, Suffolk Introduction When I was a schoolboy in Ipswich in the early 1960s, weather readings from the nearby Belstead Hall were reported in the local newspaper, the East Anglian Daily Times. Recently I was asked about preserving the records, and the whole of the archive material from the owner has now been passed to the Chilterns Observatory Trust, a charity set up by Philip Eden (2010). I have copied the data covering the severe winter of 1962/1963, and this article describes the highlights of it from those readings together with some of my personal recollections of that remarkable season. Beltead Hall is situated at N, 1 06 E (TM ), about 5km southwest of Ipswich (Figure 1). A range of observations was maintained by three generations of residents from 1900 to 2003; the station was registered with, and regularly inspected by, the Met Office. The observation site was located at about 33m amsl in a large garden within agricultural country, so was reasonably representative of rural conditions: the nearest housing areas in Ipswich that winter were at least 2km distant. The instruments used were standard dry- and wet-bulb and maximum-minimum thermometers within a Stevenson screen, and a standard 5-inch raingauge. Temperatures were recorded in degrees Fahrenheit: at 0900 UTC to one decimal place, and maxima and minima to the nearest degree. For the purposes of presentation and analysis here all the readings have been converted to degrees Celsius, to one decimal place. This article is concerned with the period from 1 December 1962 to 5 March My school was three and a half miles from my house, and I used to cycle, or occasionally walk, there and back: the journey that winter was often made in below-freezing temperatures but, being young, after a few minutes walking or cycling the circulation got going, and I cannot recall ever feeling uncomfortable or miserable. Brown (2006) 1 km Belstead Brook Old A12 and Simons (2008) describe the severity of the winter in some depth, but a study of the single-site daily temperatures here reveals a number of subtle variations over the period, reflecting the local effects of changes of air mass: there were several short periods when daytime maxima rose slightly above freezing. The key events in the synoptic pattern of the winter are illustrated by NOAA s National Centers for Built since 1963 Belstead Hall IPSWICH Figure 1. The location of Belstead Hall weather station. The built-up area of Ipswich in 1963 is shaded. As well as a significant urban expansion since then, major new road alignments for the A14/A12 lie adjacent to the A12 crossing of Belstead Brook and separate Belstead from the south of Ipswich. Figure 2. Belstead Hall temperatures, 1 December 1962 to 5 March N Environmental Prediction (NCEP) reanalysis charts for 0000 UTC. Daily temperature readings The full series of daily temperature observations is shown in Figure 2. December opened with a spell of cold weather, with frost occurring each night up until the 8th. The daily maxima were mostly between 3

2 and 6 C: the rainfall observations over this period record a trace on some days, probably from overnight fog. From the 8th to the 21st, it was generally mild notably so on the 15th. Rainfall was recorded on several days during this period, culminating in 14.5mm on the 20th. The long, cold period commenced on 23 December, with an 0900h temperature reading of 2.4 C on the 23rd. Box 1 summarises some salient features of the severe winter, and the daily mean temperatures throughout the cold period are shown in Figure 3. Box 1. Summary of temperature statistics 23 December 1962 to 3 March days out of 72 recorded minima at or below 0 C The night of 22/23 January brought the lowest minimum temperature of 13.3 C: noted by the observer as Coldest night this century Periods during which all minima were at or below 0 C were: 23 December to 27 January 30 January to 7 February 10 February to 4 March Total number of days with maxima at or below 0 C were: December 2 January 14 February 4 Periods during which all daily mean temperatures were at or below 0 C were: 23 December to 3 January; 7 to 26 January; 30 January to 7 February; 10 to 12 February; 14 to 16 February; 18 to 25 February; 2 March Figure 3. Daily mean temperature at Belstead Hall, 23 December 1962 to 3 March Although the maximum temperature was above freezing on several days (2 10 January, January and most of February), the repeated overnight frosts, often severe on successive nights, meant that the duration of such levels was shortlived and, overall, the experience of persistent cold was paramount. The intensity of cold may be demonstrated by a degree-day approach, which reflects both the duration and the cumulative effect of the low temperatures. Using a start date of 22 December and an arbitrary initial temperature of 0 C, the cumulative total of daily mean temperature was calculated and a degree-day plot was produced, as in Figure 4. Some periods of less intense cold can be identified by a small reversal of the overall downward trend in early and late January: the greatest degree-day deficit was degc, reached on 25 February. The author is not aware of similar statistics compiled for other severe winters, such as 1947, but comparisons would be interesting. The method could also serve as a useful means of assessing the severity of cold spells as they develop. Snowfalls The first snowfall, on December, missed most of East Anglia, although the observer noted some slight precipitation on the 26th, 28th and 29th. The first snowfall at the station, which in fact proved to be the heaviest fall for the whole of the period, occurred on 30 December: an estimated rainfall equivalent of 9.6mm was noted. Compared to some other severe winters (such as that of 1947), snowfalls were not excessive in 1962/1963 at least in East Anglia. Other falls occurred on 3/4 January (8.4mm rainfall equivalent) and 19/20 January (9.4mm). The observation station at East Bergholt, some 7km to the southwest of Belstead, reported snow lying from 31 December 1962 to 28 February 1963, with the maximum depth of lying snow, 15cm, being recorded on 20 and 21 January. The low temperatures ensured there was minimal thawing, but it was clear to me at the time that as the winter progressed, the depth of lying snow diminished markedly: I thus had first-hand observational experience of the process of ablation. I was also able to observe that a medium-sized pebble placed on a solid frozen bowl of ice gradually worked down into the ice by a combination of pressure and temperature that caused thawing at the contact zone. These two facts were relevant to our O-level geography lessons on both meteorology and glaciers! Aspects of the 1962/1963 winter in Suffolk Figure 4. Cumulative daily mean temperature. Synoptic patterns during the period Information on the weather structure in terms of general circulation and upper-air 19

3 Aspects of the 1962/1963 winter in Suffolk conditions can be examined from the NOAA/NCEP archive of reanalysed daily charts for 0000 UTC. A selection of these charts is used to illustrate some of the key events during the period. On these illustrations the colour coding applies to the geopotential height of the 500mbar pressure level. Broadly, precipitation is likely to be of snow at least wherever blue is shown: this indicates a low height for this pressure level and hence the presence of deep cold, lowdensity air. It should be noted, though, that very cold surface air may have quite a shallow depth and not be reflected in the colour coding at the 500mbar level. In particular, strong winter continental anticyclones, once well-established, tend to be associated with extremely cold surface air and a marked temperature inversion at maybe only a few thousand metres above the ground, with warm air above this: the heavier warm air results in a significant raising of the height of the 500mbar pressure level. Onset of cold weather Figure 5 for 21 December shows a southward extension of deep cold air over central Europe from a cold pool centred over the eastern Baltic and Russia, and a centre of surface high pressure lies below it. There is still a westerly weather type over the British Isles. Over the next 48 hours, a major change in type gets under way as the Scandinavian anticyclone intensifies and moves westwards, bringing an easterly surface airflow towards the east and south of the UK (Figure 6): very cold air moved into southeastern Britain during the evening of 22 December. Arrival of heavy snow The chart for 0000 UTC on 30 December 1962 (Figure 7) illustrates the situation which brought the first heavy snowfall at Belstead Hall. Cold surface air has extended over the whole of the north Atlantic, with a detached upper air cold pool lying to the west of Ireland. The Scandinavian anticyclone collapsed rapidly over the Christmas period, and the nearest strong anticyclone is now over Greenland; with a depression over Biscay, a strong easterly airflow is set up over southern Britain, where a frontal system (not illustrated on these charts) emanating from the depression brought a blizzard. It is a typical wintry weather set-up, which is further illustrated and described by Dukes and Eden (1997). Core cold period Following the snow on 30 December, very cold but mostly dry weather became established and lasted throughout almost the whole of January, although there were a few more snowfalls notably as indicated in Figure 8, which shows the pattern at 0000 UTC on 20 January 1963 when a pool of very cold air and a corresponding surface trough over southern England brought heavy snow showers and strong winds (Pike and Webb, 2011). 20 Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 21 December 1962 immediately prior to the onset of the severe cold weather. (Courtesy NOAA/NCEP reanalysis project.) Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 23 December 1962 the incursion of cold air from the east. (Courtesy NOAA/NCEP reanalysis project.) A less cold interlude Figure 9 shows a different set-up on 28 January. After several exceptionally cold days as anticyclonic conditions took over, less cold surface air has come around the top of the anticyclone from the Atlantic across the British Isles, and there was a slow thaw, especially in the north and west. The observer at Belstead Hall recorded precipitation on each day from 27 January to 3 February (Table 1). Unfortunately he does not indicate if this fell as rain or sleet/snow: my own recollection is of a period of damp, misty weather with drizzle and freezing rain, which gave way to light snow as the cold air returned towards the end of this period. The late winter weather The cold weather, with mostly light surface winds from the near Continent, re-established itself from 30 January. However, although persistent, the cold during February was not generally as intense as it had been in January. It finally gave way in early March: Table 2 illustrates how the temperature slowly rose from 25 February, with the last overnight frost coming on 4 March. I still remember noticing the different feel

4 Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 30 December 1962 the arrival of heavy snow. (Courtesy NOAA/NCEP reanalysis project.) Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 20 January 1963 the core cold period. (Courtesy NOAA/NCEP reanalysis project.) Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 28 January 1963 a short incursion of less cold weather. (Courtesy NOAA/NCEP reanalysis project.) to the air when checking our maximumminimum garden thermometer on the morning of 4 March. After over two months of frosty cold affecting the nostrils, the air smelt somehow softer. Figure 10 shows the chart at 0000 UTC on 1 March. The surface high has shifted eastwards to a position between Norway and eastern Europe, whilst a very deep depression is situated south of Greenland. Surface air is being drawn north from the Iberian peninsula and France on the eastern flank of a trough to the west of the Bay of Biscay. The movement of weather systems from the west brought higher temperatures and, eventually, some significant rainfall, 29.2mm being recorded from 9 to11 March. Discussion The winter of 1962/1963 can without doubt be called exceptional in terms of extreme temperature and its duration and extent: its impact was felt all over the British Isles. The conditions described in this article are a snapshot at a single location, and could no doubt be similarly replicated at most observation stations over the UK and Ireland during that period, though the timing and magnitude of extremes, and the incidence of snowfall, will doubtless vary from place to place. Examination of mean temperature data for East Anglia from the Met Office Regional Datasets (downloaded from www. metoffice.gov.uk/climate/uk/datasets), reveals that temperatures for January and February 1963 were both below 0 C. There have been no other occurrences since 1910 of these two months consecutively recording sub-zero mean temperatures, although 1942 came close see Table 3. It is tempting to dismiss the shorter periods of extreme cold in recent winters as mere trifles in comparison. All of the last four winters, from 2008/2009 to 2011/2012, gave snow and periods of sub-zero temperatures over large areas of the British Isles (Prior and Kendon, 2011a). The period from mid-december 2009 to mid-january 2010, and late November through December 2010, produced extreme cold over unusually extended periods over the UK and also the Republic of Ireland (Met Eireann, 2010; 2011). The December of 2010 was the coldest December since 1890, and in Edinburgh there has been no colder December in a composite record back to 1764 (Eden, 2011). All three winters bore similarities to 1962/1963, but the cold spells were of shorter duration. Late January and February 2012 brought a sustained spell of severe cold weather to much of continental Europe, leading to the icing over of the Danube and the coast of the Black Sea and it may be merely chance that this outbreak only extended briefly into the British Isles. Aspects of the 1962/1963 winter in Suffolk 21

5 22 Aspects of the 1962/1963 winter in Suffolk Table 1 Temperature and precipitation at Belstead Hall from 26 January to 3 February Date Temperature at 0900h ( C) Maximum Minimum Rainfall equivalent (mm) 26 January Nil 27 January January Trace 29 January January Trace 31 January February February Trace 3 February Table 2 Temperature readings at Belstead Hall from 25 February to 5 March Date Temperature at 0900h ( C) Maximum Minimum 25 February February February February March March March March March Figure mbar (gpdm) contour height and surface pressure for 0000 UTC on 1 March 1963 the end of the long, cold winter. (Courtesy NOAA/NCEP reanalysis project.) The position of the British Isles at the western fringes of Europe still places us on a meteorological knife-edge; the risk of protracted cold spells still exists and the somewhat shocked reaction of the public, media and various authorities to severe cold after a run of mild winters should alert concerned bodies. Some reaction by government and industry after the cold weather of late 2010 has been noted (Prior and Kendon, 2011b), but how far lessons learned will be retained remains to be seen. As it is, at the time of writing, the impact of successive (relatively) dry winters is more acutely apparent than the already-fading collective memory of their cold spells. Table 3 The five coldest starts to a year: mean monthly temperatures ( C) for January and February in the East Anglian Region (Source: Met Office Regional Datasets). Year January February Acknowledgements I am grateful for the permission of the family of the last observer at Belstead Hall, Anthony Wilson Esq, to use these data for publication. What started off as a short recollection of probably the most memorable weather event of my life grew into a somewhat larger piece. I am grateful to the anonymous reviewers of the draft for many suggestions, and for a set of references that will enable readers to obtain a wider view of the event. References Brown P The severe winter of over Great Britain: synoptic patterns and resulting weather. Int. J. Meteorol. 31: Dukes M, Eden P Weather records and extremes, in Climates of the British Isles. Hulme M, Barrow E (eds). Routledge: London; pp Eden P Weather in my life. Weather 65: Eden P Weather log for December Weather 66 (2). Met Eireann Exceptional Weather Events: Cold Weather Win ter 2009/10. Irish Meteorological Service: Dublin, Ireland. Met Eireann Exceptional Weather Events: Extreme Cold Spell November/ December Irish Meteorological Service: Dublin, Ireland. Pike WS, Webb JDC An historical and climatological note on snowfalls associated with cold pools in southern Britain. Weather 66: Prior J, Kendon M. 2011a. The UK winter of compared with severe winters of the last 100 years. Weather 66: Prior J, Kendon M. 2011b. The disruptive snowfalls and very low temperatures of late Weather 66: Simons P Since Records Began. Collins: London. Correspondence to: J. Dent dent650@btinternet.com 2013 Royal Meteorological Society DOI: /wea.2040

6 Editorial postscript As the author indicates, the foregoing article essentially provides a localised snapshot of the momentous winter of fifty years ago. This journal s Weather log did not appear in its current format until that for April 1965, but in the early 1990s in a joint venture by two Weather Board members, the current editor and the late Ken Woodley, a series of full logs of this nature was produced for some earlier eventful months. That for January 1963 appeared in our January 1992 issue (47:15 18), and the text of the summary and the tabular data from it are reproduced below. January 1963: The coldest January on record The very cold spell that started just before Christmas 1962 persisted throughout January. Although depressions approached south-west Britain and gave blizzards in the south anticyclones over or to the north of the country were the dominant feature of the month, resulting in a very dry month in most districts. It was also mostly a sunny month, especially in the west, where some places reported their sunniest January of the century. Strong easterly winds affected most places early in the month. There were snow showers and, as troughs edged north into southern Britain, some longer spells of snow in places. Severe blizzards affected parts of south-west England and south Wales on the evening of the 3rd, with drifts of up to 15 feet blocking roads and railways and isolating towns and villages. However, the snow turned to rain for a time on the 3rd and 4th; freezing rain was reported in some areas. The second week of the month brought sunny spells and snow showers, with increasingly severe night frost and daytime temperatures barely above freezing; 16 C was recorded at Gatwick and Eskdalemuir early on the 13th. There was also persistent freezing fog around this time, chiefly over the Midlands; Shawbury reported a maximum of 7 C on the 12th. It was rather less cold for a time in midmonth as winds backed northerly. However, a strong easterly airflow became established during the 17th, and the following week was the harshest of the winter. A minimum of 22.2 C was recorded at Braemar on the 18th. Gales and heavy snow showers affected much of the south and east around the 19th; typical late-afternoon temperatures that day over south-east England were 5 C with a mean wind speed of about 25mph. There was freezing rain in places on the 20th. The 21st to 28th was mostly fine, as a very strong anticyclone drifted south across the country. At first, the days were mostly sunny with persistent frost. The nights became exceptionally cold as winds fell light. By the 24th there were areas of persistent freezing fog. The temperature fell to 20.6 C at Stanstead Abbotts (Hertfordshire) early on the 23rd and then rose to only 8 C at Ross-on-Wye. It was much less cold on the 26th as the anticyclone retreated to Ireland and Atlantic air invaded the British Isles. Some places were free of frost that night for the first time in the month. Pressure exceeded 1048 millibars in southern Scotland on the 27th, but then fell as fronts moved south across the country, and very cold, snowy weather was back in most places by the 30th. Aspects of the 1962/1963 winter in Suffolk Mean maximum ( C) Diff. from 1921 to 1950 average (degc) Mean minimum ( C) TEMPERATURE SUNSHINE RAINFALL Diff. from 1921 to 1950 average (degc) Highest maximum ( C) Lowest minimum ( C) No. of Air frosts Alt. Map no. and place (m) 1 Stornoway Dyce Leuchars Renfrew Eskdalemuir Tynemouth Dishforth Ringway , , Valley Watnall Elmdon Gorleston , Cardington Ross-on-Wye Rhoose , Kew Obsy Boscombe Dn , Thorney Is Various Plymouth , Aldergrove No. of days with grass min <0 C Total for month (hours) % of average Maximum duration (hours) Days with no sunshine Total for month (mm) % of average Max. fall in 24h from 0900 (mm) Days with no rain ( 0.1mm) Days with thunder Days with snow or rain and snow Days with snow lying at 0900 Days with fog (vis <200m at 0900) 23