Given below, are the final December 2018 statistics for Edinburgh, Gogarbank from all of the data which I have available which are:

Temperature (°C):

Lowest Min: -3.1 (on 24/12)
Highest Min: 9.4 (on 31/12)
Mean Min: 2.9
Min. Anomaly: +1.8

Lowest Max: 2.7 (on 15/12)
Highest Max: 12.1 (on 29/12)
Mean Max: 8.0
Max. Anomaly: +1.4

Ave. Temp.: 5.5
Temp. Anomaly: +1.6

Air Frosts: 7 (56.9% of 1981-2010 average)
Ice Days: 0

Rainfall (mm):

Total for Month: 37.8 (59.4% of 1981/2010 average)
Wettest Day: 6.0 (on 7/12)
Rain Days: 8 (62.0% of 1981/2010 average)
Dry Days: 12
Longest Dry Spell: 4 days (11/12 to 14/12, 25/12 to 28/12)
Highest Number of Days without a single dry day: 8 days (1/12 to 8/12)

Sunshine Totals (hrs):

Total For Month: 48.0 (136.0% of 1981-2010 average)
Sunniest Day: 4.9 (on 3/12 and 24/12)
Sunless Days: 12

Conclusion:

Overall, a very poor start to the winter of 2018/19.

December 2018 was a milder than average month and just like in the CET region, it was the warmest December here since 2015. This was a completely snowless month here with the exception of some wet snow which was brought about by Storm Deirdre for a short period of time that left a temporary rather slushy deposit on the roads and pavements for a while. Furthermore, the number of air frosts was very disappointing to the extent that I didn't even manage to wake up to a single frost during my Christmas break in the Scottish Borders.

In contrast to what has been happening in the rest of the UK, December 2018 was a substantially drier than average month here not just in terms of the actual rainfall amounts, but also in terms of the number of official rain days. It was also a sunnier than average month with the actual amounts of sunshine being almost on a par with what we got during the same month in 2017, although there was more completely sunless days this time.

Fairly normal, mean temp was near the average until the last few days.
It's interesting that cold months earlier in the year were not averaged out by the nice spell in summer here - which was not especially warm with highest temp only 27.9c
Similarly the brief droughty period did not last long in fact July with 98mm was the second wettest month, after November with 118mm

Average temperature = 5.5°C (+1.2C)
Average temperaure year = 8.8C (-0.2C)
Average humidity = 89%
Average dewpoint = 3.9°C
Average barometer = 1013.0 mb
Average windspeed = 8.2 mph
Average gustspeed = 11.5 mph
Average direction = 233° ( SW)
Rainfall for month = 59.4 mm (-13mm)
Rainfall for year = 783.9 mm (-70mm)
Maximum rain per minute = 0.4 mm on day 18 at time 19:29
Maximum temperature = 11.6°C on day 06 at time 16:49
Minimum temperature = -2.0°C on day 11 at time 02:25
Maximum humidity = 93% on day 11 at time 04:42
Minimum humidity = 76% on day 07 at time 13:26
Maximum dewpoint = 10.2°C on day 06 at time 16:49
Minimum dewpoint = -3.0°C on day 11 at time 2:25
Maximum pressure = 1033.4 mb on day 24 at time 20:38
Minimum pressure = 988.3 mb on day 02 at time 19:41
Maximum windspeed = 34.5 mph from 270°( W ) on day 08 at time 00:16
Maximum gust speed = 54.1 mph from 270°( W ) on day 08 at time 00:19
Maximum heat index = 11.6°C on day 06 at time 16:49
Avg daily max temp :7.7°C
Avg daily min temp :2.9°C
Growing degrees days :0.0 GDD
Total windrun = 5441.7miles
Frost days= 5
-----------------------------------
Daily rain totals
-----------------------------------
04.1 mm on day 1
01.5 mm on day 2
00.4 mm on day 3
06.7 mm on day 5
00.2 mm on day 6
06.0 mm on day 7
00.4 mm on day 8
00.2 mm on day 12
00.9 mm on day 13
09.7 mm on day 15
04.1 mm on day 16
01.9 mm on day 17
15.3 mm on day 18
01.7 mm on day 20
04.3 mm on day 21
00.4 mm on day 23
00.2 mm on day 25
00.4 mm on day 29
00.4 mm on day 30

Temperature (°C):

Minimum -1.4 day 13

Maximum 13.3 day 02

Highest Minimum 10.6 day 06

Lowest Maximum 4.9 day 14

Air frosts 4

Rainfall (mm):

Total for month 39.9

Wettest day 6.9 day 18

Rain days 18

Dry days 13

Wind (mph):

Highest Gust 22.1 day 09

Gale days 0

Pressure (mb):

Maximum 1030.4 day 31

Minimum 988.0 day 20

Days with snow falling 0

Days with snow lying at 0900 0

https://blog.andrewlalchan.co.uk/watford-weather-december-statistics/ 

Given below, are the final December statistics for The Botanic Gardens in Edinburgh from all of the data which I have available which are:

Temperature (°C):

Lowest Min: -3.4 (on 24/12)
Highest Min: 9.6 (on 31/12)
Mean Min: 2.8
Min. Anomaly: +1.5

Lowest Max: 0.9 (on 24/12)
Highest Max: 12.1 (on 6/12)
Mean Max: 7.7
Max. Anomaly: +0.7

Ave. Temp.: 5.3
Temp. Anomaly: +1.1

Air Frosts: 7 (63.6% of 1981-2010 average)
Ice Days: 0

Rainfall (mm):

Total for Month: 33.8 (55.6% of 1981/2010 average)
Wettest Day: 6.2 (on 2/12)
Rain Days: 9 (78.9% of 1981/2010 average)
Dry Days: 9
Longest Dry Spell: 3 days (12/12 to 14/12, 26/12 to 28/12)
Highest Number of Days without a single dry day: 8 days (1/12 to 8/12)

Sunshine Totals (hrs):

Total For Month: 58.6 (126.8% of 1981-2010 average)
Sunniest Day: 5.5 (on 3/12 and 24/12)
Sunless Days: 13

I know that I'm a bit late in posting this, but it took quite a lot longer than normal for me to get all of the data which was required for that.