October 2018

Temperatures
(all temperatures in degrees Celsius; all averages 1961 – 1990)

Mean daily maximum: 13.9
Difference from average: +0.7

Mean daily minimum: 5.8
Difference from average: -0.5

Mean air temperature: 9.8
Difference from average: 0.0

Absolute maximum: 20.9 (10th)

Absolute minimum: -0.5 (29th)

Mean grass minimum: 3.4

Absolute grass minimum: -2.3 (29th)

Mean concrete minimum: 4.7

Absolute concrete minimum: -0.7 (29th)

Number of ground frosts: 2

Number of air frosts: 11

Mean soil temperature at 30cm depth: 11.6

Mean soil temperature at 100cm depth: 12.5

Rainfall
(all totals in millimetres; all averages 1961 – 1990)

Total for the month: 50.6
Difference from average: -2.0

Percentage of the average: 96%

Wettest day: 11.4 (12th)

Number of rain days (>0.25mm): 15

Number of wet days (=> 1mm): 7

3-month total rainfall to 31st October: 147.2
Difference from average: -24.8

6-month rainfall total to 31st October: 261.4
Difference from average: -84.8

12-month rainfall total to 31st October: 634.2
Difference from average: -14.8

Humidity
(averages for 09:00 hours GMT)

Relative Humidity: 83%

Sunshine
(all averages 1961 – 1990)

Total for the month: 95.9 hours
Difference from average: +2.8

Percentage of the average: 103%

Mean daily sunshine: 3.1 hours
Difference from average: +0.1

Sunniest day: 7.6 hours (10th)

Number of days with no recorded sunshine: 3

Cumulative total sunshine since 1st January: 1195 hours
Difference from average: -22.5

ISSN1350-483

Comments on October 2018
Mean air temperature was exactly average for October at Durham. Days were warmer than normal, but not exceptionally so; by contrast, nights were colder than normal, the lowest mean minimum since 2012. Mean air temperature was also the lowest for October since the very wet and cool October of 2012. Had it not been for a very cold last six days, October would have been at least a degree warmer and much more like recent Octobers have been in Durham. There were some very warm days earlier in the month with two maxima over 20°C (10th, 13th). In the last six days, the maximum never reached 10°C with only 6.9°C on the 30th. Whilst 6.9°C felt rather chilly, it only ranks equal 133rd lowest for an October day since 1850 (n=5239); a maximum of only 1.8°C on 21st October 1859 would have felt very much worse! There were 11 ground frosts but only 2 air frosts (for one of which the minimum was barely below zero: -0.03°C).

Rainfall was just about average for October and all longer-term totals are now below average. Sunshine hours were also very close to average.

Emeritus Professor Tim Burt
Department of Geography
Durham University