December 2016 was dominated by high pressure, so much so that the month average of 1024.9 was the highest ever recorded here in December. The maximum pressure was 1043.9 millibars, recorded at 19:20 on the 27th, also a record high for December. This was the second highest pressure ever recorded here, beaten only by the 1044.6 millibars on February 7th 2012. The lowest pressure in the month was 1010.2 millibars at 17:30 on the 23rd, this was the highest minimum pressure in any December.
The highest temperature recorded in the month was 13.3°C at 13:10 on the 8th, with the lowest being -1.8°C at 07:45 on the 5th. The average temperature for the month was 5.9°C, 0.8°C above the mean. The average daily high temperature was 8.2°C, 1.0°C above the mean. The average daily low temperature was 3.2°C, 1.1°C above the mean. The warmest day was the 9th with an average temperature of 11.4°C, with the coldest day being the 29th with an average temperature of -0.1°C. There were five frost days. At 11:37 on Christmas Day, the temperature reached 13.1°C making it the warmest Christmas Day so far recorded here. The previous best was 12.9°C set in 2015. The maximum temperature of 1.2°C at 14:23 on the 29th was the lowest daily maximum temperature since January 21st 2013 when the maximum temperature only reached -0.1°C.
The highest dew point was 12.3°C at 12:46 on the 8th, with the lowest being -2.6°C at 07:45 on the 5th. The average dew point in the month was 4.7°C. The high wind chill was 12.0°C at 13:10 on the 8th, with the lowest wind chill being -2.4°C at 02:52 on the 29th. The monthly average wind chill was 5.0°C. December 2016 was a very dull month with only 3.78 hours of sunshine in the month. The sunniest day was the 26th with 1.68 hours.
Rainfall was recorded on 24 days and totals amounted to 16.8 millimetres. The wettest day was the 10th with 5.0 millimetres. The average rainfall for December is 48.2 millimetres. Only December 2010 with 15.8 millimetres was drier. The highest rain rate was 35.0 millimetres per hour on the 10th. There was no recorded snow in the month.
With high pressure keeping the Atlantic storms at bay, winds were very light for the month. The average wind speed was 3 mph and the average gust speed 5 mph, both below average. The highest recorded gust speed was 40 mph at 14:57 on the 23rd. This was the third highest wind gust of 2016. The average maximum wind speed of 23.00 mph at 12:45 on the 23rd was the highest of 2016. The wind run was 2,510 miles and the dominant direction was 207°.
The maximum solar radiation was 334 w/m² on the 4th, with the average for the month being 20 w/m². The U. V. Index remained at 0 for the whole month.