January seemed a cold month, but the many snowy days were deceptive and it was in fact a little above average temperature overall; nights were warmer but days colder than the average. The grass minimum temperatures were higher than expected because of the snow cover, meaning that, unusually, minimum air temperature was often lower than the grass minimum. Rainfall was above average for the 10th month in a row. Not surprisingly, the 12-month running total was the highest on record, beating the previous month’s total. Much of the precipitation fell as snow. Sunshine was a little above average.
Despite seeming rather cold, February was only just below the long-term average, with days very slightly above average and nights just below. Six of the last twelve months had been below average and the 12-month average temperature was now down to 8.7°C. February was the first month with below-average rainfall since March 2012. Even so, long-term totals remained well above average, and indeed the 12-month total to the end of February 2013 was the wettest for any 12-month period at Durham since records began in 1850. Given a dry month, it was not unexpected that sunshine was above average, bright days being a welcome compensation for the relatively low temperatures.
March 2013 came in like a lamb and went out like a lion! It started mild, with the warmest day of the month on the 2nd. It ended unseasonably cold: several days did not reach 2°C towards the end of the month and the lowest night-time temperature was on the 31st. The mean maximum was the 4th lowest since 1900, the lowest since 1969. The mean minimum was equal 10th coldest (with 1969) since 1900, the lowest since 1962. Mean air temperature was equal 8th coldest since 1850, the lowest since 1969. The 12-month running mean for mean air temperature now stood at 8.2°C; the last time it had been this low was September 1994. The 12-month running mean had been 10.2°C only a year before. Notwithstanding the low temperatures, rainfall was just above average, with 17 rain days recorded. Given that March 2012 was very dry, this meant that, paradoxically, the 12-month total had risen again: the total to the end of March 2013 was once more a record for Durham, over 1100mm in a 12-month period for the first time since 1850. It was also the 7th dullest March since 1882, with the lowest sunshine total (61.7 hours) for March since record-breaking 1996 (only 29.3 hours, very dull indeed).
April is the cruellest month, wrote T.S. Eliot. April 2013 felt very disappointing but in fact temperatures were only just below average. Until the 13th, only one day exceeded 10oC; thereafter they all did. The absolute maximum (16.9°C) is quite typical for April but nowhere near the 23.3oC of April 2007. Spring seemed very slow in coming. It was a dry month, less than half the usual amount of rainfall. It was only the 2nd month in the last 12 to have had below-average rainfall (February 2013 was the other). For the 5th month in a row, the 12-month total was above 1000mm, but much lower than at the end of March; April was dry whereas April 2012 was extremely wet. Despite the low rainfall total, sunshine was only just about average.
May felt disappointing although in fact mean air temperature was just a little above average; daytime temperatures were just a little above average and night-time temperatures just a little below. Rainfall was well above average so that the running 12-month total remained above 1000mm for the 6th month in a row, a remarkable sequence. There were heavy falls on the 15th (21.4mm) and especially on the 18th (40.8mm), the latter causing extensive flooding in the Durham area. Rainfall intensity was extraordinary on the morning of the 18th with 12.2mm in one hour (08:00 – 09:00 BST) and 10.2mm the next hour. Hours of bright sunshine were less than average so that the accumulated total remained well below average for the year so far. Overall, Spring was cold therefore, 33rd equal lowest temperature since 1850.
Temperatures in June were above average, but not exceptionally so. The mean maximum was above normal whereas the mean minimum equalled the average. Only four days had maxima above 20°C. It was a dry month: the 3-month and 6-month cumulative totals were again finally close to average whereas the 12-month total was still well above average, but below 1000mm for the first time since the end of November 2012.
In contrast to everything that had gone before, it was the warmest July since 2006 and therefore the second warmest month on record at Durham since 1850. The absolute maximum (28.4°C) on the 9th was the warmest day at Durham since 18th July 2006. Only 5 days had a maximum below 20°C with 5 days above 25°C. The highest night-time minimum was 16.6°C on the 24th. The absolute minimum of 8.1°C has only been exceeded twice in July since 1962: in 1983 and 2004. The highest daily rainfall total of 39.2mm (28th) was large by Durham standards but only the wettest day since 18th May. This one day accounted for the monthly total being just above average. There were only 8 rain days, the lowest July total since 2006. The 12-month running total remained very much above average. As with rainfall, sunshine hours were just a little above average too.
It was the 18th equal warmest August on record at Durham since 1850 and the warmest since 2004. Whilst the warmest days were at the start of the month, a continuation of the July heat wave, there were nevertheless 18 days with a maximum above 20°C. Combined with an exceptional July and an above-average June, this made for a very warm summer (mean air temperature; 15.8°C): the warmest summer since 2003 and the 6th warmest on record. Rainfall for the month was just above average, once again because of one especially wet day, in this case 5th August when 32.6mm was recorded, remarkably the 3rd day with over 25mm already this year. For the summer as a whole, the rainfall total was just below average. Hours of bright sunshine were below average, indeed the 45th dullest August since 1882. For the summer as a whole, sunshine ranks only 50th out of 130 years’ record. Using the Davis index of summer weather, which weights sunshine, maximum temperature and rainfall, summer 2013 scored 744 and ranked only as the 34th best summer since 1886. On this basis it was only the best summer in Durham since 2006. Maybe it seemed better than it was given the woeful summer of 2012, the 2nd worst on record.
As a whole September was just above average temperature; it felt warmer because of warmer than average days but minimum temperatures were below average and there was an early ground frost on the 8th. September would have been a dry month – only 9 rain days – but for the exceptional total on the 6th when 63mm fell in 18 hours. Hourly totals of 6, 12 and 9mm during the evening are exceptional. This is the 10th wettest day in Durham since 1850 and the highest total since 17th July 2009 when 64.2mm was recorded. September was another dull month and cumulative sunshine hours for the year remained well below average.
October was the 10th warmest on record, although only the warmest since 2006. Four of the warmest 10 Octobers have come since 2000. There was the 7th highest mean minimum temperature and the 19th highest mean maximum. It was the wettest October since 2004, the 28th wettest since 1850. October was again a dull month, the 9th dullest October since 1882.
November temperatures were below average but it was only the coldest November since 2010. Rainfall was just a little below average. It was a much sunnier month than October, well above average. It was the 2nd equal sunniest November on record (with 1922) since 1882, beaten only in 1947. Autumn temperatures were above average (+0.4°C), but not exceptionally so. It was the 30th wettest autumn on record since 1850.
December was warmer than November: it was the warmest December since 1988 and the 11th highest on record since 1850. The mean maximum was the 6th equal highest (since 1900) and the mean minimum was the 9th equal highest. There was the lowest number of ground frosts since 2002. Despite average rainfall, sunshine was well above average, although the least sunny December since 2007.
For the year as a whole, the mean air temperature was 9.0°C, ranking equal 134th in 164 years. Whereas the 12-month running mean was only 8.2°C at the end of March, temperatures recovered well thereafter. 2013 was another wet year. The total of 764.6mm is the 23rd wettest year on record at Durham since 1850. In terms of all possible 12-month totals (n=1957), 2013 was the 330th highest total, well into the top quartile therefore. As noted earlier, the 12-month total to March 2013 was the highest for any 12-month period on record (1143.8mm) and, whilst the calendar year 2013 was drier than 2012, it was still well above average. Not surprisingly, the combined total (1797.6mm) for 2012 and 2013 is the highest for two consecutive calendar years combined at Durham since records began in 1850, beating 2011/12 and before that 1930/31. There were only 164 rain days despite the high total. In contrast there were a number of notable wet days: 10 days with 15mm or above and 4 days with 25mm or above. Only 7 years since 1850 have had more than 4 days above 25mm, most recently 2012 and before that 2000. Finally, in terms of sunshine, 2013 was another dull year, just a few more hours than the previous year. It ranked only 36th in a 131-year record.
Professor Tim Burt
Department of Geography