2006 was another very warm year at Durham, only marginally less warm than the warmest year on record, 2004. Both July and September were exceptional, previous records being broken by a wide margin. It was drier than normal, but the wet months of November and December prevented a much worse deficit.
Although there were some cold days in January, maximum temperature rose above zero every day. There were also some mild days too, with an absolute maximum of 11.9°C on the 11th, although this was the lowest for January since 2001. Overall, all three temperature means were above average; mean air temperature was also the lowest since 2001. The dry December continued throughout January, with only 40% of the expected monthly total. There were the fewest number of rain days since 1992, and it was the 25th driest January since 1852. All three long-period totals were now below average again, although the long-term rainfall deficit in the North East was clearly much less serious than in the South East. Despite grumbles in the media about the gloomy nature of January, sunshine totals were only just below average. However, the number of days (12) with no recorded sunshine was the largest January total since 1996.
Whilst the mean air temperature for February was below average in the south of the country, Durham reflected conditions generally across the northern part with a mean air temperature 0.8°C above average. Nevertheless, it was not a particularly warm February, ranking 91st in 157 years. It was a somewhat mixed month with some chilly days towards the end of the month, but with 5 days having maximum temperatures above 10°C. The lowest daily maximum was 0.9°C on the 2nd. Like February, the overall winter average temperature was also 4.0°C. This was the lowest since 2001 but even so, the running 10-year mean for winter mean air temperatures reached 4.5°C for the first time. The average temperature for the winter ranked 103rd in 156 years of record. February was another dry month. The winter total of 86.6mm was not as low as last year but even so it was the 22nd driest winter since 1852-53 (2005 ranks 11th). All long-term rainfall totals were now below average, as might be expected. The 24-month total up to and including February 2006 (1211.8mm) was the lowest since February 1998. This is not a particularly low 24-month total, ranking 514th in a total series of 1827 such 24-month totals, but nevertheless reflects the impact of a second dry winter, an unusual occurrence in recent decades. Interestingly, if rainfall totals for the last two winters are added together (161.4mm), this was the 2nd driest total for a pair of winters on record since 1853-54, only beaten by 1858-59, a very much drier pair only totalling 91.7mm between them!
March was a cold month and, remarkably, the first month of below-average temperatures since October 2004. The mean air temperature was the lowest for March since 1996, and the 37th coldest in 156 years. In this respect, it was not extremely cold therefore, but still most unusual in recent years. Of the 36 colder Marches since 1850, 14 occurred in the 19th Century and only 3 have been since 1964. Daytime temperatures were disappointing with a mean maximum -1.9°C below average; the absolute maximum of 13.5°C was the lowest for March since 1987. Despite the cold, rainfall was slightly above average. Sunshine was well below average, the 20th dullest March in 123 years of record. Even so, there was less sunshine in March 2005. 2006 had therefore started in a very dull way with 86 hours fewer than the average, almost one hour per day. After two wet Aprils in 2004 and 2005 (both totals in the top 20% for April), this was a dry April, with only 65% of the monthly average. Temperatures returned to their regular above-average state after the cold March. Given low rainfall, it was not surprising that the monthly total of bright sunshine hours was above average for the first month this year. Wind speed was well above average and there was a notable gust of 87kph on the 13th. May was a very wet month, 12th wettest since 1852 and the highest May total since 1983. Mean air temperature was equal to last year and therefore the equal lowest for May since 1997.
June was warm in Durham. The mean air temperature of 14.7°C was only the highest since 2003, but that still makes it the second warmest June since 1976 and the 8th equal warmest June since 1850. Unusually, the record holders are not recent years: 1940 is the warmest June on record at Durham (15.9°C) followed by 1858 (15.6°C). Like mean air temperature, the mean daily maximum was the highest since 2003 and, before that, 1976, and in all the 7th highest since 1950. Mean minimum was less far above average; nevertheless, it was still the 6th equal highest since 1950. The absolute maximum of 26.2°C on the 11th was the 6th highest since 1962; this may well have been the warmest Sunday for the Durham Regatta on record. The absolute minimum of 5.9°C was the third highest for June since 1961, bettered only in 1970 and 2003. June was a very dry month, the lowest June total since 1996 and 11th lowest since 1852. Despite the low rainfall total, there was only an average amount of sunshine.
July was the warmest on record at Durham since records began in 1850. It beat the previous record (1983) by a massive 0.7°C. The mean maximum (24.3°C) was the highest on record for any month, beating the previous record of 23.1°C for August 1995, and was a huge 5.0°C above the mean maximum for July. The absolute maximum saw the temperature in Durham exceed 30°C for the first time since August 1995; indeed only three months have recorded maxima above 30°C since 1962: August 1995 (30.3°C), July 2006 (30.5°C) and August 1990 (32.5°C). Daytime temperatures exceeded 25°C on 18 days, and only three days had a maximum below 20°C. The mean minimum temperature was less far above average, but still the third highest for July since 1950 and the fifth highest for any month. Of the air temperature measurements, only the absolute minimum for July was unexceptional. A rainfall total of 6.6mm for the month seemed very low but accorded with the Met Office anomaly map which showed the Durham area to be below 25% of the monthly average. Measurable rain was only recorded on four days. This was the second driest July on record at Durham since 1852; only 1878 (4.7mm) has been drier. All long-term measures of accumulated rainfall were now well below average, with the 12-month total to 31st July 2006 more than 100mm below the long-term average. It was the third sunniest July since 1882 at Durham, beaten only by 1911 and 1955. In addition to these two months, the July 2006 sunshine total has also been beaten only once in August (1995), once in May (1971) and three times in June (1940, 1949, 1957); the sunshine total of 297 hours in 1940 remains easily the highest ever recorded at Durham for any month, with July 2006 ranking 8th highest for any month. There was a full 3 hours sunshine above the average each day and the overall total was 60 % above the average. It was the first July since 1993 with sunshine recorded every day. After the record-breaking July, Durham returned to normality in August. Indeed, the mean maximum temperature was exactly average, and only a higher than normal mean minimum allowed the mean air temperature to be a little above average. Rainfall too was just about average. It was, however, a very dull month indeed: only August 1912, with a measly 57 hours, has been duller in August since records began in 1882.
Following July rather than August, this was the warmest September on record at Durham since records began in 1850, beating the previous record (1949) by a massive margin of 0.7°C. It was also the first time since 1956 when September has been warmer than August (This has only happened 5 times since 1850 including this year). Both mean maximum and mean minimum were records for September, as might be expected given the overall mean, with the mean maximum exceeding 20°C for the first time. The absolute maximum of 26.7°C is also a record. For the 7th month out of 9 this year, rainfall was below average. Sunshine was about average for the time of years but it was nevertheless a much sunnier month than August. October was the third warmest on record at Durham since 1850, beaten only by 1969 and the record holder, 2001. The mean maximum temperature was the highest since 2001 whereas the mean minimum was the highest since 1969, as might be expected, the only two years where mean air temperature has been higher. In many ways the most remarkable aspect of temperatures in October was the small range, with neither very high, nor very low temperatures recorded. The relatively constant, mild weather was reflected in the fact that rainfall was only just above normal and sunshine hours a little below average. This suggests a mild maritime air flow, without the extremes associated with high pressure systems. November was the 4th warmest on record since 1850, the warmest since 1994 (the record holder at 8.4°C) and only otherwise exceeded in 1899 and 1938. Both mean maximum and mean minimum were well above the long-term average. Despite protestations from newly arrived students about how much it rains in Durham, it was not in any way exceptional – only the wettest November since 2000, when almost twice as much rain fell! Thirty two Novembers have been wetter since 1852. The 3-month (autumn) total was around average for the period, but the 6-month and 12-month totals remained well below average. November was a sunnier month than normal, sunnier indeed than October. It was also a windy month, particularly towards the end of the month. As a result of three very warm months, 2006 was the warmest autumn on record at Durham, beating the previous record (2001) by a massive 0.9°C. It was 1.3°C warmer than the very warm autumn last year, which now ranks only 6th on the all-time list. November was a wet month, well above average.
Despite some cold days over the Christmas period (which were also very dull), there were milder days in the first half of December and at the end, so that it ended up well above average temperature. Overall, all three measure of temperature were 1.1°C above average. It was the warmest December since 1997 but (with 2004 and 2002) only ranks 32nd warmest since 1850. It was a wet month with well above average rainfall, the 17th wettest December since 1852. The fall of 24.2mm on the 11th was the wettest day of the year. Despite the rainfall, it was the 6th sunniest December since 1882, but 2003 and 2004 were both sunnier. In the week from the 22nd to the 28th, only the 27th recorded any bright sunshine at all (1.1 hour). Although there were strong winds on New Year’s Eve, the strongest gust was on the 12th at 114 kph.
2006 was a remarkable warm year, the second warmest on record at Durham since 1850, only a negligible 0.02°C cooler than 2004. Every month except March was above average, with the year as a whole 1.4°C above the 1961-1990 mean. The warmest ten years at Durham are now as follows (to two decimal places):
Year and average temperature
2004 – 9.96°
2006 – 9.94°
2003 – 9.88°
1949 – 9.83°
2002 – 9.80°
1990 – 9.75°
2005 – 9.71°
1945 – 9.66°
1999 – 9.61°
1989 – 9.58°
Given the length of the Durham temperature record, it is remarkable that two months in 2006, July and September, proved to be the warmest on record, previous records being broken by a wide margin. Rainfall in 2006 was below average, and would have been an exceptionally dry year except for the wet months of May, November and December. Overall, it was only the 42nd driest year on record, dry but not remarkably so. Despite the warmth and below average rainfall, hours of bright sunshine were only just above average.
The extreme warm of recent years is most remarkable: only five months in the last sixty have fallen below the monthly mean (calculated for the period 1961-1990) and even if the 1971-2000 means are used instead, this only increases to seven. Even if there remains debate about the exact causes, evidence of global warming in Durham is now unarguable.
Professor Tim Burt
Department of Geography