The Weather at Durham in 2019

Although mean air temperature was only modestly above the 1981 – 2010 mean, this was nevertheless the equal 42nd warmest January in 170 years, just into the upper quartile. Maximum temperatures were more above average than minimum temperatures, reflecting the dry, sunny conditions. Reflecting conditions generally across NE England, January was exceptionally dry: the 7th driest January since 1850 and the driest since 1989. Not surprisingly, it was a sunny month, the 13th sunniest January since 1881.

It was the sunniest February at Durham since records began in 1882 and the 3rd warmest February since records began 1850, beaten only by 1998 and 1945. After a very dry January, February was also drier than normal, but not exceptionally so, ranking only 69th lowest in 170 years. Given the very dry January, this was the 15th driest onset to a calendar year (January + February rainfall) since 1850, the lowest such total since 1964. Interestingly, ten of the fifteen lowest J+F totals occurred more than one hundred years ago. Unlike many places in the country, 26th February 2019 was not the warmest February day on record at Durham. This accolade falls to 28th February 2012: 17.4°C. 26th February this year was “only” the 4th equal warmest February day on record (17.4°C), in a list of 4801 February days. Still, this compares very favourably with 28th February last year, when the maximum was a chilly -2.1°C! The coldest February day on record at Durham is 16th February 1855 when the temperature reached no higher than -4.3°C.

Winter was the equal 6th warmest, beaten only by 1998, 1999, 2007, 2014 and 2016 – notably, all within the last two decades. It was the equal 20th driest winter since 1850. Most notably, it was the third sunniest winter at Durham, only exceeded in 2000 and 2015.

To large extent, March showed its usual “lion” and “lamb” colours. There were chilly, wet and very windy days in the first half of the month, with warm, dry, sunny days later on. Daily maximum temperature was above 10°C from 16th onwards with both 28th and 29th receiving more than 10 hours sunshine. Unlike the rather cool March in 2018, this was the equal 10th warmest March since 1850, although only the warmest since 2017 (which ranks equal 8th warmest). Night-time temperatures were especially high, ranking equal 6th warmest, but again beaten by 2017 which ranks 3rd. Day-time temperatures were well above average too, ranking equal 13th. The 12-month running mean is back above 10°C for the first time since June 2017. The rainfall total was just above average. Other than 1st March, there was rainfall every day from 2nd to 18th, followed by 11 days with no rain at all! Sunshine hours just managed to exceed the exceptional February total, notwithstanding three extra days in March and a higher solar elevation! It was the 43rd sunniest March since 1882. This was the 6th equal warmest start to a year (with 2000 and 2012). Of the top five, only 1938 comes before 1989.

Mean air temperature in April was just a little above (+0.4°C) the 1981 – 2010 average. This sounds disappointing but it was nevertheless the equal 35th warmest in 170 years, the coolest April since 2013. The mean minimum was also modestly (+0.4°C) above average. Mean maximum was rather higher above average, equal 20th highest since 1900. The 12-month average remains above 10°C. The four days between 19th and 22nd all had maxima above 19°C; Easter Saturday was the warmest day of the month with Easter Sunday only 0.2°C cooler, some very welcome weather for the holiday weekend! The dry spell continued with the 12-month total the lowest since March 1997. Whilst by no means a record-breaker, this is nevertheless becoming a very significant drought. This is the 105th lowest 12-month total in 2021 possible totals since 1850. This has been the 26th driest start to a calendar year since 1850. It was the 60th driest April in 170 years, although April 2017 was marginally drier. Sunshine was exactly average for the month. Easter Sunday was the sunniest day of the month.

This was the coldest May in Durham since 2012, with both mean daily minimum and mean air temperature below the 1981 – 2010 average. Nevertheless, May 2019 still ranks =39th highest in 170 years of record. There was a disappointing start to the month with four days (6th – 9th) having a maximum below 10°C, including the 8th with a maximum of only 8.0°C. Only four days had maxima over 20°C, three in the middle of the month (13th – 15th). The 12-month average has again fallen below 10°C. It was another dry month: four out of the first five months of 2019 have been below average rainfall, amounting to the 19th driest five-month start to a year since 1850. All long-period totals remain well below average. Sunshine was well below average too, indeed a lower total than in April. However, this is not such a rare occurrence in fact, having happened in 36 years since 1880, but it was very different to last year when May sunshine was more than double that in April. All in all, hardly a prelude to summer, as so often May can be!

In terms of spring as a whole, the mean air temperature was 8.7°C, equal 14th warmest since 1850. It was a dry spring (188.4mm) but not exceptionally so, the 66th driest in 170 years. There was a slightly below-average amount of sunshine (391.9 hours), the 72nd sunniest since 1882, but not nearly so dull as 2016 (344.1 hours).

Mean air temperature for June was just above average, equal 43rd highest since 1850. Mean maximum was just below average for June (equal 49th lowest since 1900), but mean minimum was well above average (equal 20th highest since 1900).

This was the wettest month since January 2016 and the wettest June since the very wet summer of 2012. Nevertheless, the 3-month and 6-month totals remain well below average. In line with many places in the country, there were high totals on 12th (23.8mm) and 13th (17.2mm), with the heaviest rain between 22:00 on 12th and 02:00 on 13th when hourly totals of 4.4, 3.8 and 3.6mm were recorded. Not surprisingly, June was a dull month with a sunshine total well below average, less than four hours of bright sunshine per day. It was the 14th dullest June in Durham since 1882, although June 2016 was worse – so too were 2014, 2007 and the dullest June on record 2012.

The highest temperature ever recorded at the Durham Observatory since 1900 was in the early afternoon of 25th July when 32.86°C was reached. There was a higher temperature recorded on 16th July 1876 of 33.6°C but this was obtained from within a “Glaisher screen” which were well known for overestimating maximum temperatures. On that same day in 1876 the maximum recorded in the “North Shed” (on the north side of the Observatory) was only 30.1°C, a more likely reflection of the true maximum that day. 32.86°C is the highest temperature recorded at Durham since a Stevenson screen was installed in 1900. Note that Gordon Manley did not analyse maximum and minimum temperatures before 1900, confirmation that maximum and minimum temperatures could not be trusted before that. This was the same day as the national record was broken at Cambridge Botanic Gardens and at the Radcliffe Observatory in Oxford, with a daily record of temperature from November 1813, the highest ever temperature there was also recorded. Mean air temperature in July was equal 8th highest since 1850, but July 2019 was not quite as warm as July 2018. It was the highest mean minimum since 1900, beating the previous record set in 2003. The mean maximum was also well above average, equal 14th highest since 1900. Rainfall was a little above average, mainly because of a fall of 26.6mm on the 27th. It was the 24th dullest July since 1882.

It was the 9th warmest August at Durham since 1850 with the equal 2nd highest mean minimum and the equal 18th highest mean maximum since 1900. Once again night-time temperatures helped to raise the overall mean, suggesting better summer weather than it often felt during the day. There were four hot days towards the end of the month, but 17 others where the maximum remained below 20°C; the maximum of only 15.7 on 11th was particularly disappointing. Rainfall was a little above average, wetter than July but not as wet as June. It was a dull August, not as bad as the previous two Augusts but nevertheless the 23rd lowest total for any August since 1882.

It was the 7th equal warmest summer on record at Durham since 1850 (15.7°C), exactly the same as last year; 2003 holds the record at 16.2°C. It was the 15th wettest summer (261.4mm) since 1850, the wettest since 2012. It was also the 6th dullest summer since 1882 (351.4 hours), although both 2012 and 2017 were worse; the record holder is 1912 with a miserable 223 hours. Spring was sunnier than summer this year. This is not that rare in fact: 37 years since 1882 have had a sunnier spring than summer at Durham. Using the Davis index of summer weather, 2019 was the equal 34th worst summer at Durham since 1900; by contrast summer 2018 ranks 91st in a list of 120 years. This poor result in 2019 reflects high rainfall and lack of sunshine rather than low temperatures.

September was warmer than average but not greatly so: both the mean maximum and mean minimum were 0.4°C above average and mean air temperature just 0.2°C above average. There was some variety of daytime temperature with a maximum of just 13.6°C on 9th yet three days into the twenties later in the month: 21.8°C on 19th, 22.2°C on 20th and 22.7°C on 21st. It was a wet month, with the wettest day being the last day of the month. Heavy rain had been forecast for “Freshers’ Sunday” (29th) so perhaps it was with some relief that the rain held off until the next day, a total fall of 21.4mm. Yet again, sunshine was below average. The sunniest day was 19th, also one of the warmest, some very welcome “Indian summer” weather!

It was the coldest October at Durham since 2012; the October mean air temperature ranks 73rd since 1850 (n=170) so just below the median. The mean maximum was the lowest for October since 1993 and 25th lowest since 1900. Even so, there were only five ground frosts and no air frosts. The rainfall total ranked 132nd in 170 years. It was the fifth month in a row with above-average rainfall and the third with a total above 80mm. It was largely a gloomy month, except for a few sunny days at the end of the month when anticyclonic conditions dominated, active fronts being well to the south over southern and south-western England. Overall it was the least sunny October since 2013, the 11th lowest since 1882. 1960 has the lowest October sunshine total – only 40.9 hours. Altogether a disappointing October, rather more what might be expected mid-autumn but rather unlike some of the mild Octobers recently experienced.

November was a disappointing month: cold, wet and dull. Even so, it was only the coldest November since 2016. Daytime temperatures were well below average but night-time temperatures were above average, no doubt reflecting the cloud cover. The mean maximum temperature was 27th lowest since 1900, into the bottom quartile; 2016 was 17th lowest. By contrast, 2011 had the second-highest mean maximum for November and 2015 the fourth highest so perhaps November is becoming more variable. Notably, the lowest air temperature recorded was on the last day of the month as settled anticyclonic weather moved in.

It was the coolest autumn since 2012, 0.5°C below the 1981 – 2010 average. Nevertheless, autumn 2019 ranks equal 67th highest in 150 years and 9.3°C is the median value, so it was hardly an extremely cold autumn, simply a disappointing one given generally warmer ones this century. From June onwards, all months have recorded above-average rainfall. Whilst not quite as wet as June, this was the 17th wettest November on record since 1850 and the wettest since 2012. This helped contribute to the 13th wettest autumn on record at Durham and, again, the wettest since 2012. Almost as dull as November 2018, November 2019 was the 18th dullest November at Durham since 1882. This contributed to the 11th dullest autumn on record, the worst since 2001.

Like the previous year, December temperatures were well above average. Mean air temperature was the equal 23rd highest since 1850, just 0.1°C below the 2018 value. Despite being a dry month, the mean minimum temperature was rather more above average than the mean maximum. Frequent cloud cover clearly helped to maintain night-time temperatures; usually dry winter months have cold, clear nights.

For the 4th year in row, December rainfall was below average, in this case the 36th driest December at Durham since 1850. Nevertheless, there were 19 rain days, an indication of the cloudy maritime air masses that dominated the month. The previous six months were all above average, so long-term accumulations remain well above average. Sunshine was only a little above average, but even so, it was still the 24th highest sunshine total for December since 1882.

A warm December helped contribute to the 9th warmest year on record at Durham since 1850 (9.77°C). Other than 1949, all the warmer years have been this century. The stand-out observation was undoubtedly the highest temperature ever recorded at the Durham Observatory on 25th July when 32.9°C was recorded. This is a stark reminder that temperature records are today most likely to be broken at the “hot” end of the scale. If Durham is indeed experiencing a climate emergency – and I believe it is – this record seems clear evidence of climate warming, locally and globally. Not surprisingly, given the very wet summer and autumn, 2019 was a wet year, but only the 45th highest on record: winter and spring were dry, so the annual total of 735mm was not exceptional. Overall, it was a poor year for hours of bright sunshine, the 25th dullest year on record at Durham since 1882. Another warm, wet and dull year!

Finally, please note that I have now moved to using 1981 – 2010 averages. I am also using wind data from the automatic weather station on the roof of the West Building at the University’s Lower Mountjoy campus. The anemometer at the Observatory has been defunct for a decade now so at least the West Building data give some indication of recent conditions but there is no long-term average to compare with, of course. Please note also that I have reverted to data analysis where the standard meteorological “day” is 0900 – 0900, rather than midnight to midnight. Whilst automatic data collection makes it easy to calculate averages for a calendar day, it seems that most, if not all, weather stations have kept to the 0900 threshold. Thus, if Durham data are to be exactly comparable to other stations, we must revert to the 0900 standard, even if seems to make little sense in an era of automatic data collection.

	January	February	March	April	May	June	July	August	September	October	November	December	Year
Mean air temperature	4.2	6.4	7.2	8.2	10.7	13.5	17.2	16.5	13.3	8.9	5.7	5.4	9.8
Difference from average	0.4	2.3	1.3	0.4	0.2	0.2	1.6	1.1	0.2	-0.9	-0.7	1.5	0.6
Mean maximum temperature	7.2	10.6	11.1	12.9	15.3	17.5	21.6	20.5	17.6	12	8.1	8	13.5
Mean minimum temperature	1.2	2.2	3.8	3.5	6.0	9.4	12.9	12.5	9.1	5.9	3.2	2.8	6.0
Absolute maximum temperature	12.2	16.8	16.6	22.3	21.0	26.8	32.9	28.1	22.7	15.2	12.3	12.4	32.9
Absolute minimum temperature	-6.8	-6.6	-0.8	-2	-0.9	3.9	6.5	9.1	2	0.6	-3.8	-2.6	-6.8
Number of air frosts	13	6	1	4	1	0	0	0	0	0	7	7	39
Number of ground frosts	17	12	8	9	5	0	0	0	1	5	12	12	81
Rainfall total	11.8	30.4	52.8	30	35.6	111	70.2	81.2	84.2	88.4	106.6	32.8	735.0
Difference from average	-40.45	-11.5	8.9	-23.0	-11.0	53.9	14.7	19.8	28.8	27.7	36.8	-26.3	78.0
Rainfall %	23	73	120	57	76	194	127	132	152	146	153	55	112
Highest daily rainfall	3.2	7.6	13.4	9.8	9.2	27.6	26.6	17.4	21.4	14.4	17	6	27.6
Number of rain days (>0.1mm)	15	11	18	8	18	16	16	20	19	18	25	19	203
Sunshine hours	74.5	118	120.6	140.9	130.4	115.1	121.1	115.2	108.4	64.1	43.7	61.9	1213.9
Maximum daily sunshine	7.1	8.7	10.9	11	10.5	11	9.9	9.3	8.6	7.3	6.5	6.1	11

Emeritus Professor Tim Burt
Department of Geography
Durham University