Category Archives: cold spell

‘So much for global warming…’

Since notably cold weather struck at the end of February I’ve lost count of the number of times I’ve heard this phrase uttered by the public and some sections of the press.

Top 20 cold
Top 20 cold anomalies

The ‘Beast from the East’ (versions 1.0 and 2.0) really captured the imagination in an age where everything has to have a label slapped on it; any message that these cold spells are ‘weather’ and not ‘climate’ seems to get lost.

Both spells, indeed the general pattern of our late winter weather, were driven by the stratospheric sudden warming event that lead to a split polar vortex in February – leading to a very cold end to the month and a mean temperature anomaly of -2.5C, the greatest monthly anomaly since March 2013.

To put it into perspective, however, it was nothing like some of the anomalies that occurred in the early 19th century: January 1814, for example, saw a monthly anomaly of -8.2C and coincided with the last occasion a frost fair was held on the Thames. Januaries back then were generally very cold, the 1801-1831 average monthly mean was -3C, that’s 8C colder than the most recent 1981-2010 average!

So climate now is much warmer but that is not to say that anomalously cold months can’t happen. February 1986 saw an anomaly of -5.6C, the 13th= greatest cold anomaly in my local dataset going back to 1797.

top 20 warm
Top 20 warm anomalies

The cold December of 2010 recorded an anomaly of -4.2C, 76th= greatest cold anomaly, while anomalies of -4.1C recorded in January 1979 and March 2013 were 77th=.

With the warming climate it is no surprise that most warm months happened very recently. The balmy month of December 2015  saw a positive anomaly of 5.4C.

The ‘Beast from the East 2.0’ was caused by a narrow tongue of extremely cold air from Russia scoring a direct hit on the UK. The odds of this happening must have been low but it is an example of how, when the synoptics of the atmosphere line up perfectly, anything is possible.

And it is an example how even in a warming climate the UK can still be subject to anomalous cold and warmth at any time of the year.

As the author Mark Twain reportedly once said: “The climate is what you expect; the weather is what you get.”

gfs
The upper air anomaly of the ‘Beast from the East 2.0’. 
anom
This graphic shows positive and negative monthly anomalies since 1797 against a generally warming climate

Because the above graphic is crowded I created one of anomalies since 1970. The upward trend is the same.

1970

march 1st

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Beast MkII or just a late March cold spell?

After the severe spell at the end of February that lasted into this month there’s lots of excitement / dread (*delete as appropriate) that the synoptic conditions that brought very cold air from our east is about to return.

The latest run on the GFS model shows that very cold air (-10C at 5,000ft) could be over us by next Sunday, with the ECM 12Z operational looking particular cold. ec

Snow this late in the year is very rare in the London area though, if the conditions are right, a blizzard is not impossible, as happened during the spring of 1952 when a two-day blizzard at the end of March brought drifts up to 6ft deep in the Chilterns.

Much more likely will be severe, possibly record breaking frosts. The coldest March night since 1959 across the London area occurred on the 3rd in 1965 with -7.4C recorded at Heathrow. Central London fell to -5C on the same night.

A look back at cold spells in March reveals that while snow was very scarce in London and the Home Counties it can be common on high ground from the Peak District northwards.

A history of March cold

1812: Luke Howard in The Climate of London noted that “great inclemency of the weather” on the 21st March disrupted mail deliveries between the north of Scotland and  Carlisle. The road between Appleby and Brough was impassable because of snow and between Sheffield and Manchester and Bradford and Halifax the snow had drifted from “two to three yards deep”.

Mail deliveries were also disrupted across South Wales.
In Plymouth a “a most tremendous gale from SW the whole of last night and this morning” brought flooding.
Howard’s account would confirm a classic battleground scenario of mild Atlantic air from the south pushing against cold Polar continental air in the north.
His own records from Stratford show a couple of cold days from the 16th, highs never lower than 2C, the coldest night on the 24th, being -4.4C. On the 20th he mentions snow in the morning followed by rain.
Wanstead mean: 4.9C (-2.8C) rainfall: 74.4mm (183%)

The following accounts of cold spells in March are recorded on the site London Weather.

1962: The first ‘spring’ month was colder than any month during the preceding winter. Frosty nights were much more frequent than normal, and sleet or snow fell on 10 days, although amounts were often trivial . On the 5th, the maximum temperature was only 2.2 C. Towards the end of the month, north to northeast winds were replaced by somewhat, cloudier milder, and moister south-westerlies. Atlantic fronts brought rain bands, and on the 29th nearly 10mm was measured.
Wanstead mean: 3.3C (-4.4C) rainfall: 36.5mm (90%) sun: 95.4hrs (88%)

1964: The first week of March was mostly cold with wintry showers and a fresh northeast wind. The temperature on the 7th only reached 2.3C. The second week was changeable and milder, and the high on the 13th was near 14C., but on the 15th, rain turned to sleet and gave a total of 26mm as cold air slowly encroached from the east. Nearly 15mm of rain fell on the 19th as milder air returned, but the rest of the month stayed mostly rather cold and changeable.
Wanstead mean: 4.9C (-2.8C) rainfall: 80.4mm (90%) sun: 63.5hrs (58%)

1969: The first week was mainly dry, and although dull and cold at first, it became fairly sunny and milder but with severe frosts. Overnight on the 6th/7th the minimum temperature was close to minus 8C. During the second week it became dull and wet, but after a cold start temperatures rose above average. Cold north-easterlies returned on the 16th with a high of only 3C., and cloudy, rather cold, and often wet, weather persisted until westerlies returned on the 29th.
Wanstead mean: 4.6C (-3.1C) rainfall: 53.2mm (131%) sun: 55.8hrs (51%)

1979: The first 12 days of March were changeable and windy with temperatures mostly above average. A wave depression formed on a cold front and produced 23mm of rain on the 13th, and as this depression became slow moving to the east of the country the rain turned to sleet and snow on the 14th, and continued into the 15th and 16th with highs near 3C. After mid month, the weather became less unsettled and milder, and the high on the 25th was near 15C.
Wanstead mean: 5.8C (-1.9C) rainfall: 96.5mm (237%) sun: 100.5hrs (92%)

1985: After a changeable start to the month, pressure built, and it became mostly dry, although often rather cloudy, with temperatures close to normal. On the 15th, showery rain turned to snow during the morning, and several cold and unsettled days followed. Sleet or snow fell on 5 days, and on the 21st the temperature failed to rise above 5C. Sharp frosts occurred, and although it then became less cold, the 26th was a miserable day with 11m of rain falling.
Wanstead mean: 5.9C (-1.8C) rainfall: 44.1mm (108%) sun: 100.5hrs (87.4%)

Winter 2017/18: 27th out of 72

A few years ago I devised a winter index to try to decipher how modern winters ranked against legendary seasons, such as 1947 and 1963.

With the media hyping conditions last week, which were severe in many parts of the country, it is very difficult for many to gauge just how conditions compare with previous winters.

My findings show that this winter so far stands 27th. It is possible that further snowfall that results in lying snow at 9am between now and April will boost the position higher though, given recent years, this would seem unlikely.

index

Last week’s cold spell, while containing some impressive statistics, is put into perspective when it is compared with other severe spells since 1960. A decent cold spell but no record breaker in the form of a 1962/63.

Perhaps it is the advent of social media, the plethora of constant updates of the latest feet-deep snowdrifts and instant tales of heroism in the face of icy adversity, that has made this cold spell seem far more severe than it actually was in the minds of many; February / March 2018 was the first truly social media-driven cold spell.

Record cold pools and snowfalls

This week has the potential to see new temperature records set or matched as very cold air moves in off the continent.

Whilst amounts and location of snow are very difficult to estimate at more than 24hrs to 48hrs away there is no doubt that the incoming air is very cold indeed.

In the early hours of Wednesday one weather model is showing extremely cold air (496-504 DAM ie very low thickness) just off the coast of Scotland. In the last 60 years there have been only three occasions where air approaching this thickness (500 DAM and lower) has been recorded in the UK:

February 1st 1956: Hemsby, Norfolk
February 7th 1969 at Stornoway, Outer Hebrides
January 12th 1987 at Hemsby.

thick
Radiosonde (weather balloon) ascents will make very interesting reading this week

With the deep cold air in place the potential for snowfall comes once the air starts to become unstable. East London, and much of the east coast, best falls come where convergence lines ‘streamers’ form.

streamer
One example of a streamer is forecast to occur on Tuesday

If persistent, these ‘Christmas tree’ features are capable of producing snowfall accumulating at the rate of 5–7cm per hour in especially cold
outbreaks, albeit often very locally. The steep thermal contrast between the very cold air and the current warm anomaly in the North Sea could make any snowfall very heavy indeed.

Streamers during the cold spell of January 1987 saw 30cm fall widely with some up to 65cm in Kent and 45cm in south Essex. Parts of Cornwall saw up to 40cm.

During a cold spell in February 2009 thundersnow was recorded – the favoured spot this time being parts of Surrey which saw 30cm.

Personally the most snow I have recorded during a cold spell was in February 1991. A very deep cold pool, not unlike what is forecast this week, covered much of the south. in air approaching 500 DAM. Days and days of snow followed dumping knee-deep powder in my local park in suburban East London. Reported depths included 20cm at St James’ Park in the centre of London, and 38cm at Rettendon, Essex.

There is a very good paper on cold pools and snowfall here.

beast

 

 

 

The most potent cold spells since 1960

With met models now coming into reliable range it now looks odds on that very cold air from the continent will be in place across most of the UK from early next week.

The big question is how long will the cold last and how much snow will fall? While the latter looks likely at some point once the air is in place it is impossible to pinpoint where and how much any given place will receive at this range.

Screen Shot 2018-02-22 at 09.01.04
The 00Z op run of the ECMWF model has the really cold air arriving at 00Z on Monday 26th.

In terms of longevity latest data shows the spell could have real staying power though my experience with models over the years has shown that they can overcook the potential of a cold spell.

I’ve lost count of the number of times when excited enthusiasts proclaim that an incoming cold spell is going to last as least three weeks; the reality being that the intensity of the cold has gone after four or five days. Cold spells since 2008 often arrive as a ‘blob of cold air’ from the continent that eventually gets ‘warmed out’; it’s been a very long time since we had a cold spell that’s been fuelled by a continual feed of air off the continent.

Screen Shot 2018-02-22 at 09.02.23
By Saturday 00Z the really cold air aloft has gone. A typical 4-5 day event?

To illustrate my point I had a look back at every cold spell in this area of suburban east London since 1960. I weeded out the feeble efforts of the last few years by only considering spells where the maximum didn’t exceed 2.8C. The results spanned from the most recent cold spell of March 2013 to the mammoth 31-day Siberian blast that began on Boxing Day 1962.

In another blog I remarked how similar the recent pattern was to February 1962. This cold spell began on the 26th and lasted 9 days. Some 7cm of snow fell, this drifting in the wind, possibly making it seem worse with only 4 hours of sunshine which would have maintained any snow cover.

One of the snowiest cold spells happened in February 2009, eight days after an SSW event that lead to a polar vortex split. This four day spell saw a total of 26cm of snow fall.

February 1991 was even snowier, the intense cold lasting some 11 days.

Looking at other February cold spells a 7-day spell occurred in 1985 about a month after an SSW event.

Overall the median length was 5 days with an average of 6cm of snow and 8hrs of sunshine.

*A survey of winters ranked for temperature and snow can be found here.

spells

rank cold

 

1960

 

 

 

 

 

 

 

 

 

 

 

 

 

The severe cold spell of February 1991

The cold spell of February 1991 saw unusually deep snowfall in central London. The 20cm recorded at St James’s Park on the 8th was the greatest cover recorded at the site since the severe winter of 1962/63.

summ821991
Courtesy of the Met Office

My own memory of the event was that the synoptics evolved fairly quickly. I was away at university at the time and had to be back for a family event that weekend. After seeing a forecast predicting that a foot of snow was on the way I jumped on a train a day earlier than planned and returned to London. The following morning all hell had broken loose as deep snow paralysed public transport.

Snow fell on the following 6 days with no thawing as the temperature remained below zero until the 10th. The maximum of the 7th was -3C. By the 9th there was widely 20cm of level powdery snow lying. Getting around was difficult – I remember some drifts during walks into town were thigh high.

The month saw the three coldest February days of the last 60 years in central London.

By the end of the 19th all of the British Isles were snow free.

February 1991
February 1991 in suburban east London

The nine charts below show how a strong ridge of high pressure from an anticyclone over northern Sweden on the 5th brought very cold air and heavy snowfall over the following days.

These significant weather charts show the snow depths at noon from 6th to the 13th.

 

summ1021991
Courtesy of the Met Office

Ian McCaskill’s late evening BBC forecast on February 6th.

Francis Wilson’s breakfast telly forecast on February 7th 1991: “Temperatures rising from -11 to -5C. Depths in excess of a foot. It’s all downhill from now.”

Harlow, Essex, during the cold spell.

Murphy’s winter and weather prophets

It is 180 years ago this month that Patrick Murphy shot to fame after successfully predicting one of the coldest Januaries on record.

murphy
anon, “The Modern Phenomenon of a Murphy the Gullcatcher of 1838” London Saturday Journal

The month, which had started mild, completely changed during the weekend of the 8th as a SE’ly wind set in. Hard frosts and snow became a daily feature with considerable falls across Scotland, disrupting mail and causing hardship for people and livestock.

By the 20th some of the lowest temperatures of the 19th century were recorded in London. At Greenwich -16C (-11C at midday) was reported at sunrise, while Blackheath saw -20C and Beckenham -26C. By the 27th the Thames at Greenwich was completely covered with ice at high water and elsewhere in the estuary ice floes were reported.

In some parts of northern Scotland, snow was noted to fall on most days between January 8th and May 3rd. Snow was also noted in upland areas of NE Scotland in June.

‘Murphy’s Winter’ as it became known made the astrologer from Cork a small fortune from the sale of an almanac, the contents of which also successfully listed the actual date when the frost would be at its most severe.

It was possibly the first long-range weather prediction that people through the ages seem to love, whether they are right or wrong.

Many characters have emerged over the years. Yorkshire’s Bill Foggitt, who used natural signals and animal behaviour during the previous autumn, was popular in the 1980s especially when he made a prediction of a harsh winter.

Others, including the Daily Express, who probably shouldn’t be mentioned in the same breath as Foggitt, are more about the clicks they hope to generate for their publishers than any earnest attempt at being right.

  • The mean temperature locally in January 1838 was -1.5C, the second coldest January in a series going back to 1797, and as cold as January 1963.
  • mean

 

 

London Grimness index

Believe it or not it has been a sunny month this December. This region has already seen 95 per cent (38.3hrs) of what we’d expect to see in an average December.

Screen Shot 2017-12-21 at 21.30.14
A sunless outlook from the Met Office

But with a sunless day coinciding with the shortest day it is no surprise that many are feeling short-changed in the solar stakes.

A blog by XMetman on a ‘grimness index’ got me thinking how London fairs in terms of sunshine, temperature and rain in any given winter season.

Using the same criteria, and assuming that most people welcome sunshine, it can be seen that since the least grim winter of 2007-08, the season, over the past 10 years, has been growing steadily worse.

Screen Shot 2017-12-21 at 21.51.54The grimmest winter, considering statistics back to 1881, was, ironically, the 1978-79 ‘Winter of Discontent’ when widespread strikes coincided with the coldest winter for 16 years. On looking at the Top 10 of grim winters it is striking how most coincide with depressing world events, the Great War, World War 2 and the Korean War!

Screen Shot 2017-12-21 at 21.27.02

The Tory ‘Crisis? What Crisis?’ campaign was probably my first memory of a general election broadcast.

January 2017: cold and very sunny

Sunshine was a dominant feature of January 2017 in east London thanks to a long-lasting anticyclone centred over the near continent that established a feed of stable, dry air.

hoar-frost-wp
A frosty morning in Wanstead Park

It was a cold month, the mean temperature of 3.4C (1.8C below the 1981-2010 average) made it the coldest for seven years, marginally colder than the snowy January in 2013.

Though many days were dry it was also a wetter than average month with 71.5mm of precipitation recorded (134% of average) and the wettest for three years.

There were 73.8 hours of sunshine (147% of average) – the 10th equal sunniest January since 1797.

cumulonimbus
Cumulonimbus and hail were observed on 28th

The wettest day was on the 11th /12th when rain and snow associated with a LP centre that dived south-east dumped 19.7mm. This turned to snow though by 9am only 0.5cm lay in my garden. The warmest day occurred on the 11th with 10.9C recorded. The coldest maxima occurred just before obs time on the 26th when 0.6C was reached, narrowly missing an ice day. The lowest temperature occurred in the early hours of the 21st when -6.7C was recorded, the coldest minimum since January 2013.

The sunniest days were on the 18th, 20th and 21st when eight hours of sunshine were recorded.

Snow fell on 4 days and lay on 1 day. Air frosts: 14, Ground frosts: 19

screen-shot-2017-01-27-at-12-31-17
Ice on the Heronry pond was quite thick at one point

So what has February got in store. Models on the 1st suggest that after a stormy start the weather will settle down with high pressure re-establishing itself on the continent. Operational runs suggest the position of this high will again draw in very cold upper air, heralding another cold spell that this time could be more unstable with snow – thanks to the position of the anticyclone being further north than it was in January. There are also suggestions that a sudden stratospheric warming event currently underway may also disrupt the polar vortex which *could* lead to any cold around mid-month being prolonged. It is a big if, however, and it is impossible to know the final position of any anticyclone: resultant weather could be fairly cold and benign or severe and snowy.

garden-snow
Just one morning had ‘snow lying’ at 9am on 12th

My method of prediction for the month as a whole gives very little information because January was unusually wet for a cold month. After this weekend’s unsettled spell perhaps February will continue in the same vein as January: 1-2C colder than normal but predominantly dry.

So, to sum up, we’re looking at a mean of 4C, rainfall: 15mm, sunshine: 60hrs.

My forecast last month was poor: predicted mean 4.4C (result 3.4C). Rainfall: 55mm (result 71.5 mm). Sunshine: 39hrs (result 73.8hrs)

Here follows the full weather diary for January…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Cloudy start with rain pushing in from 1.30pm. A precipitous fall in temp about 2.15pm.
2nd: Sunny all day with just a few cumulus. Cold and frosty overnight.
3rd: Sunny, hazy start – the cloud building to 10.30am. Afternoon and evening felt cold.
4th: Cloudy and mild start. Brightness increased through the day though colder air arrived around dusk.
5th: Sunny, frosty start with a few clouds from time to time. The frost persisted all day on the grass.
6th: Sunny and cold start, frost lifted at 11am to leave mild-feeling early afternoon. Cloud thickened with rain arriving just before 4pm and lasting a couple of hours. Temp increased through the night.
7th: Cloudy and mild start.
8th: Cloudy and very misty on road to High Beach. Some bright spells from 10.30am. Clouding in again in the afternoon but mild.
9th: Cloudy, damp start with rain spreading in at midday then sporadically into the afternoon. Clear spells overnight.
10th: Cloudy start with odd brightness near noon.
11th: Sunny sart with just a few cumulus, this cumulus increased from time to time.
12th: Cloudy and cooler start. Started spitting at 11am before main rain arrived at noon – then rained through the afternoon and temp dropped. Reports of snow in Hampshire at 1650z. Snow in Aldersbrook at 6pm which gave a covering of icy snow and slush which lasted through until 9am on grass and cars. Just over 50% of grass covered.
13th: Bright start, snow flurries spreading in at 9.30am with heavier burst at 10.10am – snow lasted till around noon then was just cloudy – no further accumulation. Cold overnight though too much breeze for air frost.
14th: Cloudy start with some drizzle at noon. Clearing afternoon with early ground frost before turning cloudy at 1am with rain in the early hours.
15th: Light rain to start and falling on and off until 3pm.
16th: Light rain to start which went on into the morning thanks to a conveyor belt of rain – the result of being on the boundary of two air masses.
17th: Bright start with cloud and light frost, the cloud clearing with cold front off the continent. Cold, crisp afternoon followed with frost soon after dark.
18th: Sunny, very cold start with jet contrails across the sky. Sunny all day thereafter with frost after dark – not as cold as previous night – minimum was at 9am previous day.
19th: Sunny start with a few cirrus around that made for a spectacular dawn. Temp warmed up quicker than previous day with frost lifting. Cold again overnight though agitation of the lower layers prevented temp falling further than 4.1C.
20th: Sunny, very cold start with frost.
21st: Sunny, very cold start with sunshine all day, Frost lingering all day in the shade – the ground now rock hard. Coldest night since January 2013.
22nd: Sunny, very cold start with heavy frost. The frost lingered all day in the shade. Turning misty at dusk with dense patches of freezing fog developing. Another moderate frost with a 18-06 low of -4.8C.
23rd: Foggy start with dense, freezing patches on Wanstead Flats. Thinner in the village though still noticeable. The fog was present into Rush Green.
24th: Misty start with remnants of thick fog patches seen on the Flats. Thereafter sunny and pleasant in the sunshine.
25th: Foggy start though some lifted but still left misty morning. Feeling cold as wind increased. Some flurries of snow at 8.30am.
26th: Cloudy and cold, feeling raw in the wind with flurries of snow that settled on pavements in Wanstead. Cold and raw through the day with odd clear interval – temp rose to 0.2C just before dusk so no ice day. Sky cleared overnight with frost before cloud rolled in with odd flake of snow.
27th: Bright but with cloud thickening at 9.30am with moderate shower, then brighter. Sharp shower at 1510 with <5mm hail and fell at 20mm/hr. Some spectacular cumulonimbus.
28th: Cloudy start though with some brightness until 11am.
29th: Cloudy, quiet weather all day.
30th: Cloudy, uninspiring day. Some light rain at 2am.
31st: Cloudy with rain looking likely. Rain arrived in evening and fell intermittently through the night and after dawn.

There were some notable weather tweets from around the UK.

snake-pass

kings-cross

thames-barrier

storm-surge

It was also a month of extremes in Europe and elsewhere. Here are a few examples I tweeted throughout January.

nancy-ice

 

mammoth
Mammoth has recorded over 20ft of snow during January

pioneer-cabin-tree

ice-floes-in-danube

frozen-fox-danube

belgrade

parthenon

canada-icestormabruzzo-snow

 

 

 

 

 

30 years on: the January 1987 cold spell

I remember the January 1987 spell like it was yesterday. I’d arranged to stay with my aunt and uncle in a rural part of south Essex. The forecast by Ian McCaskill on the Friday night was for a cold weekend with possible snow flurries near the coast. ‘That’ll do’, I thought.

13jan1987
The upper air on 13th January 1987 was extremely cold. I don’t think it has been as cold since

I caught a mid-morning train from Romford on the Saturday morning. As I disembarked at Rayleigh I was shocked by how cold it seemed to have turned. The wait at the bus stop was made worse as my uncle was delayed in picking me up; a black leather jacket I was wearing at the time was totally inadequate.

No matter, though, as I was soon warmed up on reaching my aunt’s house, helped further by hearty home cooking. Saturday was spent driving round rural Essex: my uncle knew a few farmers and was a keen rambler. We walked a circuit around Hanningfield reservoir.

I think we watched Back to the Future that night. By the time I went to bed I remember there was a dusting of snow on the ground. For some reason I kept waking up, each time looking outside to see the build-up of snow.

snipThere was around four inches by morning and, after breakfast, I went with my uncle for a drive around the same rural spots as Saturday. The reservoir was beginning to ice over and I remember my uncle reading a Fahrenheit thermometer and saying that it was “seven degrees of frost”.

When I left Rayleigh that evening the snow was falling thick and fast and the train seemed to be travelling slower than usual. When it failed to move from Shenfield station after 10 minutes I knew something was up; the guard announced that the wheels had frozen to the tracks. Everyone disembarked and caught another. After leaving Shenfield I noticed that the snow cover gradually decreased, with just an icing-sugar like covering in Romford.

My dismay at having left a winter wonderland in Rayleigh disappeared on waking up on the Monday morning and seeing a good few inches had fallen.

BBC Breakfast presenters gravely told us how bad things were. The Isle of Sheppey was cut off and train services were severely affected – I didn’t go to school once that week because the toilets were frozen. For once the conditions, reflected in this footage from Thames News, matched the hype.

meto
Courtesy of the Met Office

Many people, including members of the Climatological Oberservers Link, also have vivid memories of the freeze.

East London: Ben Bacarisse was living in Mile End in 1987. He said:  “I was living on the 15th floor of a tower block at the time. The prolonged cold caused the main water riser into the block to freeze so no one in nearly 400 flats (there were a pair of blocks) had running
water.  It turned out to be possible to tap into the larger street main
with a stand-pipe. screen-shot-2017-01-08-at-13-35-00

Presumably the constant use kept it running though
I’d have thought it would have to be removed at night.  I don’t recall
how long that lasted but it was more than a couple of days.”

Home Counties: George Booth, who was living in Epping, Essex, at the time, explained how the weather affected him: “On the Monday (12/1/87) I accompanied a group of young scholars to the Science Museum. Despite the cold and snow they were happy to walk to the station (and they behaved themselves). It was a strange sight to see
Exhibition Road covered in that thick brownish frozen dust which occurs
when temperatures are presumably too low for treatment to be effective.
Not so good news for the school roof, however. It eventually had to be
replaced after a water tank/pipe burst after a thaw.”

warblertsGeorge, who ran a weather station in Epping, added: “On 12/1/87 the maximum temperature in Epping was -8.0c and the minimum was -10.0C. The ‘snow depth gradient’ was very steep NW-SE with SE Essex/E London and N Kent receiving much greater falls than places like Epping. However, it was the severe frost that caused many
problems, particularly in older buildings.”

Dave Cornwell, a retired scientist, from Laindon, Essex, said: “I was working as an operational scientist at a sewage treatment plant in Rainham , Essex. (London Borough of Havering, (just east of London). I remember it well because for the first time anyone could remember the sewage was freezing on entering the works through the screening bars, bearing in mind that sewage is flowing underground and starting off quite warm, usually in winter arriving at about 10-12C.

gavs“It was a major engineering problem because the heat was being conducted away by the metal bars and ice building up and blocking the flow. This could potentially have caused backing up of millions of gallons of raw sewage. A smart engineer made some improvised electrical heaters to fit on the bars and we hired massive tarpaulins to put on the north side to try and cut down the wind chill. It worked a bit till the weather turned. I remember taking the temperature at 9.30 am and seem to recall it was  -9.0C.”

top-10
The record cold spell also saw Steve ‘Silk’ Hurley’s Jack Your Body enter the charts at Number 2, a track that more or less launched the UK dance music scene

John Hall, from Cranleigh, Surrey, said: “We had a little snow on the Monday, I think it was, but it didn’t amount to much. We had to wait for overnight Tuesday/Wednesday for serious snow, but then it certainly made up for lost time. On
Wednesday morning, the gritters  must have done a remarkable job on the
roads, as traffic was moving – if slowly – on the B road that runs
through Cranleigh, and I was able to make the 8-mile journey to
Guildford Station.

“But at the station, a railwayman was standing by the entrance
telling everyone: ‘There are no trains. We don’t know when there will be
any trains. We advise you to go home.’ I managed to get a bus back to
Cranleigh, by which time the snow had just about stopped.

“I didn’t measure the depth of the snow, but my subjective impression that Wednesday morning was that it was almost a foot (30 cm) deep.  The wind wasn’t strong enough to cause too much drifting that day, but the following day it became pretty strong, and there was considerable drifting of the powdery snow, with some susceptible local roads becoming blocked. In this southern lowland region I can’t remember another such instance of this ‘delayed drifting’.”
Tudor Hughes, had the added altitude (165m) of Warlingham, Surrey, that made the cold spell even more memorable. “It was just about the most outstanding weather event for me. The 12th was a sunny day with a light NE’ly and a few inches of lying snow and the temperature just wouldn’t rise.
“After a min of -12°C it got up to -9.2°C (12-hr max) which I think is a COL record though obviously not a UK one.  The 24-hr max was -8.9°C, agreeing with the reading from Coulsdon (Ian Currie).
“In the evening some smoky-looking stratus appeared and snow fell from cloud so thin that the moon was visible.  It snowed intermittently for a further 2 days until the level depth was 39 cm.  At the top of the North Downs (Tatsfield) the depth was about 3 times that.”
Tudor added: “The temperature was below -5°C for about 40 hours and below 0°C for eleven days.  I whacked up the heating and opened the loft door.  A burst pipe and frozen tank is the last thing you want.
“The extraordinary thing about January 12th was the lapse rate.  This was no cold inversion – the higher you were the colder it was.  I reckon the maximum at the top of the Downs (877 ft) was -10°C.  There was some relatively warmer air above 700 mb but even so the 1000-500 mb thickness was 498 dam.  Not quite the purple line but well inside the brown one.”
Unlike some cold spells the severe weather was not restricted to the SE corner of England.

The South West: Len Wood, from Wembury, southwest Devon, said: “Even here on the coast this was the coldest spell I experienced since moving here in 1983. We had four successive ice days and my record min of -10.1C was recorded which still stands.

“With quite a biting easterly wind it was hard to keep our bungalow warm.
Cold was coming up through the floors so I blocked the air bricks and we covered the floors with anything we had handy, old carpet, blankets…

“I remember another effect of the extreme cold was to make all the leaves turn black on the privet hedge down the length of our garden. They subsequently fell off. The hedge did recover the next summer though.”

There is a study of the heavy coastal snowfall of January 11-13 by W.S.Pike here.

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Some more charts from Smartie on the Google Group Weather and Climate…

2m temperature and snow depth at 12 UTC 12 January 1987 from a downscaled simulation of 10-13 Jan 1987. The ERA Interim reanalysis was used as initial and boundary conditions. Contours of physical snow depth start at 2.5 cm every 2.5cm.

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The main convergence zones appear quite well resolved at DX ~12km

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This is the first downscaling grid. It has the latest ‘scale-aware’ convection scheme from WRF (Multi-scale Kain-Fritsch). The deep and shallow components should both be active (haven’t confirmed this).

Hourly output from this is used to initialise nested 6 and 2km grids. On the 6km grid the deep convection should be almost off and shallow convection still active.chart-4

On the 2km grid there is no Cu scheme ie. it’s ‘convection permitting’ in the jargon.

The plots can be compared with the letter by Lumb (Weather, 1988,, V43, 31).

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