December 2021

Sunshine out over Lyme Bay on a fine December afternoon

An mild and extremely dull month with average rainfall.

Summary for December 2021
Mean Max: 11.1ºC (+1.8ºC)
Mean Min: 5.8ºC (+2.5ºC)
Mean: 8.5ºC (+2.2ºC)
High Max: 15.3ºC 31st
Low Max: 7.8ºC 20th
High Min: 13.6ºC 30th
Low Min: -1.6ºC 2nd 
Mean Grass Min: -0.6ºC  
Grass Min: -5.6ºC 2nd 
Days  >10°C 21 Days  
Days >5°C 31 Days  
Nights  >10°C 4 Days  
Nights  >5°C 19 Days  
Rain Total (gauge): 90.2 mm (100%)
Rain Total (tipping bucket): 88.0 mm (98%)
Rain Days >0.2 mm: 19 Days  
Rain Days >1.0 mm: 14 Days  
Max 24 hrs: 20.2 mm 25th
Days without any rain: 12  
Air Frost: 2 Days  
Grass Frost: 10 Days  
Snow Falling: 0 Days  
Snow (50%) @ 9am: 0 Days  
Ice Days: 0 Days  
Thunder Heard: 0 Days  
Hail <5 mm: 0 Days  
Hail >5 mm: 0 Days  
Fog @ 9am: 0 Days  
Total Monthly Sunshine: 47.9 Hours (59%)
Most Sunshine in a Day: 6.6 Hours 10th
Average Daily Sunshine: 1.5 Hours  
Sunless Days: 0 Days  
Cloudless Days: 0 Days  
Total Possible Sunshine: 249.7 Hours  
Percentage of Total Sun: 19%  
Average Sunny Interval: 14.3 mins
Maximum UV Index: 1.3 1st
Mean Soil Temp @ 10 cm: 8.5ºC  
Min Soil Temp @ 10 cm: 6.1ºC  
Max Soil Temp @ 10 cm: 12.8ºC  
Mean Soil Temp @ 30 cm: 9.1ºC  
Min Soil Temp @ 30 cm: 6.8ºC  
Max Soil Temp @ 30 cm: 13.2ºC  
Mean Soil Temp @ 100 cm: 11.2ºC  
Min Soil Temp @ 100 cm: 9.4ºC  
Max Soil Temp @ 100 cm: 14.0ºC  
Ave 10 Min Wind >39 mph: 0.00 Days  
N: 2.29 Days 7%
NE: 1.46 Days 5%
E: 2.01 Days 6%
SE: 1.85 Days 6%
S: 6.11 Days 20%
SW: 5.48 Days 18%
W: 1.85 Days 6%
NW: 4.07 Days 13%
Calm: 5.88 Days 19%
Wind Chill Low: -3.1ºC 2nd 
Mean Wind: 3.8 mph  
Max Gust: 44 mph 7th
Mean Cloud Cover: 70%  
Mean RH @ 9am: 93%  
Rain >0.1mm/hour: 26.5 Hours  
Frost Duration: 12.1 Hours  
Air Frost in a Day: 9.2 Hours 2nd 
Mean Sea Temperature: 10.9ºC (+0.5ºC)
Normal for Month: 10.4ºC  
Max Sea Temperature: 12.0ºC 31st
Min Sea Temperature: 9.0ºC 9th
Mean Pressure @ 9am: 1013.1 hPa  
Mean Pressure: 1013.4 hPa  
Max Pressure: 1040.6 hPa 17th
Min Pressure: 985.2 hPa 28th
Max Change in 24 hours: 26.4 hPa 7th
Radiation Daily Mean: 2.48 MJ/m²  
Max Daily Value: 4.68 MJ/m² 2nd 
Min Daily Value: 1.15 MJ/m² 25th
Number of Days with Data: 31 Days  
1-Hour Maximum: 268 W/m² 5th
Starting Time of the Hour:   13:00
Max Dewpoint: 14.1ºC 29th
Min Dewpoint: -2.6ºC 2nd 
Mean Dewpoint: 6.9ºC  
Max Humidity: 100% 6th
Min Humidity: 65% 5th
Mean Humidity: 91%  
 
Weather Data for Otter Valley, Devon. December 2021
  Temp oC Grass Hum (%) Soil oC (cm) Soil DP (oC) Wind (mph) Rain Air (hPa) W/m² UV Sun Frost Sea Observations
  Min Max Min Min Max 10 30 100 (cb) Min Max Max Ave Run mm Min Max Max Max Hours Hours Temp
1 8.1 11.4 2.8 76 96 8.1 8.2 10.6 N/A 3.5 10.6 30 7.2 173 4.2 1000 1009 318 1.3 4.4 0.0 11.6 Sunny ints all day
2 -1.6 8.2 -5.6 66 99 6.9 8.0 10.1 N/A -2.6 4.0 19 1.9 46 0.0 1009 1018 272 1.3 5.8 9.2 11.1 Sunny ints all day
3 0.9 11.7 -4.4 95 99 6.8 7.5 10.5 N/A -1.8 11.3 21 1.2 28 8.6 999 1016 148 1.0 0.2 0.0 10.8 Brief sunny ints all day
4 5.0 9.6 -0.6 77 99 7.2 7.8 10.0 N/A 2.2 7.9 28 3.2 77 3.8 999 1005 399 1.2 3.4 0.0 11.1 Sunny ints all day
5 4.9 9.2 -2.2 65 93 6.7 7.7 10.0 N/A 0.4 4.8 26 6.3 152 0.6 1004 1018 270 1.2 6.1 0.0 11.0 Sunny ints all day
6 0.2 11.4 -2.2 78 100 6.3 7.2 10.0 N/A -0.7 10.1 27 2.8 66 3.8 1007 1018 310 1.2 2.7 0.0 10.5 Sunny ints all day
7 -0.6 10.4 -2.8 76 100 6.3 7.1 9.8 N/A -1.3 10.0 44 6.8 163 8.6 986 1012 206 1.2 2.0 2.9 10.8 Sunny ints all day
8 5.8 9.4 1.1 69 90 6.2 7.2 9.4 N/A 1.8 4.6 24 6.1 146 1.0 986 1002 341 1.0 5.6 0.0 11.2 Sunny ints all day
9 1.4 10.7 -2.2 76 99 6.1 6.8 9.4 N/A -0.1 10.5 23 3.0 72 2.6 994 1005 113 0.9 0.0 0.0 10.9 Cloudy all day
10 5.4 9.4 -2.2 71 93 6.4 7.2 9.4 N/A 0.4 8.3 23 6.2 148 0.4 994 1012 260 1.2 6.6 0.0 10.8 Sunny ints all day
11 2.2 11.4 -0.6 94 99 6.4 6.8 9.4 N/A 0.9 11.2 11 1.2 30 1.0 1012 1018 80 0.9 0.0 0.0 10.6 Cloudy all day
12 9.4 12.6 6.1 89 100 7.2 7.2 9.4 N/A 8.6 12.2 25 3.7 88 0.0 1018 1022 125 1.0 0.3 0.0 11.1 Brief sunny ints all day
13 11.0 12.0 0.0 93 99 7.6 7.3 10.6 N/A 10.4 11.1 21 6.4 154 2.6 1021 1025 100 0.8 0.0 0.0 11.2 Cloudy all day
14 8.9 12.6 0.0 94 99 7.8 7.4 10.6 N/A 8.2 12.0 12 1.8 43 0.0 1024 1029 56 0.8 0.0 0.0 11.1 Cloudy all day
15 11.0 12.7 0.0 88 98 8.3 7.9 10.6 N/A 9.5 11.5 10 1.5 35 0.0 1029 1035 73 0.8 0.0 0.0 11.2 Cloudy all day
16 8.6 11.9 0.0 81 99 8.5 8.1 10.6 N/A 6.9 10.8 8 0.4 10 0.0 1035 1040 112 0.9 0.0 0.0 11.1 Cloudy all day
17 6.8 10.1 0.0 78 93 8.8 8.6 10.6 N/A 4.6 7.6 11 2.4 58 0.0 1038 1041 86 0.9 0.8 0.0 11.3 Sunny ints all day
18 4.1 9.1 0.0 86 97 9.4 9.4 10.3 N/A 1.0 7.5 14 3.0 71 0.0 1037 1038 121 1.0 1.6 0.0 11.2 Sunny ints all day
19 1.1 8.0 0.0 93 99 9.8 9.6 10.2 N/A 0.3 7.2 9 1.1 27 0.0 1031 1038 162 1.0 1.2 0.0 10.9 Sunny ints all day
20 3.9 7.8 0.0 86 97 9.7 9.7 10.2 N/A 3.0 5.9 12 2.6 63 0.0 1026 1031 122 1.0 0.0 0.0 10.9 Cloudy all day
21 6.9 8.0 0.0 79 86 9.6 9.8 10.3 N/A 3.6 5.4 16 3.4 82 0.0 1022 1026 92 0.9 0.0 0.0 10.8 Cloudy all day
22 6.1 9.3 -3.9 82 93 9.5 10.0 10.4 N/A 3.5 8.3 17 4.1 97 0.0 1012 1022 110 0.9 0.0 0.0 10.5 Cloudy all day
23 4.2 13.3 0.0 91 100 9.4 9.8 10.6 N/A 3.2 13.2 19 3.3 80 1.6 1005 1012 202 0.9 1.6 0.0 10.0 Sunny ints all day
24 3.6 11.6 0.0 96 100 9.5 9.9 10.7 N/A 2.9 11.2 18 2.2 53 3.2 1000 1008 103 0.9 0.0 0.0 10.0 Cloudy all day
25 5.1 11.3 0.0 97 100 9.5 10.0 10.7 N/A 4.3 11.0 21 3.6 85 20.2 999 1001 62 0.9 0.0 0.0 10.3 Cloudy all day
26 6.0 11.7 0.0 93 100 9.6 10.1 10.8 N/A 5.1 11.1 14 0.6 15 3.0 999 1001 232 1.2 2.3 0.0 10.0 Sunny ints all day
27 6.7 13.0 0.0 92 100 9.7 10.2 10.8 N/A 6.2 12.2 25 5.2 125 10.8 985 999 206 1.0 0.2 0.0 10.3 Brief sunny ints all day
28 9.9 12.2 0.0 81 98 9.8 10.3 10.9 N/A 7.2 11.0 30 5.9 142 0.8 985 1005 146 1.0 1.1 0.0 10.6 Sunny ints all day
29 9.2 15.2 0.0 88 100 10.0 10.4 10.9 N/A 8.1 14.1 27 4.8 119 9.6 1001 1010 128 1.0 0.3 0.0 11.1 Brief sunny ints all day
30 13.6 14.2 0.0 92 98 10.2 10.5 11.0 N/A 11.6 13.7 31 10.7 389 1.6 1010 1017 124 0.9 0.5 0.0 11.4 Brief sunny ints all day
31 12.7 15.3 0.0 90 99 10.3 10.6 11.0 N/A 12.2 14.0 21 3.9 41 0.0 1017 1020 197 1.2 1.0 0.0 10.9 Sunny ints all day
5.8 11.1 -0.5 84 97 8.3 8.7 10.3 N/A 4.0 9.8 21 3.8 2879 88.0 1009 1018 170 1.0 47.9 12.1 10.9  
UV Light | Month So Far | Year So Far | Recording Data | Time-Lapse Videos | World Weather | Met Office 5-Day | Humidity Calculation | Links