January 2010

A snowy January scene in the enchanted Wistman's Wood on Dartmoor.
A snowy January scene in the enchanted Wistman's Wood on Dartmoor.
Summary for  January 2010
Mean Max: 4.9C (-3.5C)
Mean Min: -1.1C (-3.8C)
Mean: 1.9C (-3.7C)
     
High Max: 10.7C 16th
Low Max: -0.7C 7th
High Min: 7.7C 22nd
Low Min: -10.7C 7th
Mean Grass Min: -4.0C  
Grass Min: -15.8C 7th
     
Rain Total (gauge): 102.8 mm (118%)
Rain Total (tipping bucket): 88.1 mm (101%)
Rain Days >0.2 mm: 9 Days  
Rain Days >1.0 mm: 7 Days  
Max 24 hrs: 33.4 mm 16th
Days without any rain: 22  
     
Air Frost: 16 Days  
Ground Frost: 24 Days  
Snow Falling: 2 Days  
Snow (50%) @ 9am: 6 Days  
Thunder Heard: 0 Days  
Hail <5 mm: 0 Days  
Hail >5 mm: 0 Days  
Fog @ 9am: 0 Days  
     
Total Monthly Sunshine: 88h:45m  
Total Monthly Sunshine: 88.5 Hours  
Most Sunshine in a Day: 08h:45m 30th
Average Daily Sunshine: 02h:51m  
Sunless Days: 4 Days  
Cloudless Days: 8 Days  
Total Possible Sunshine: 264h:53m  
Percentage of Total Sun: 34%  
     
Mean Soil Temp @ 30 cm: 2.6C  
Min Soil Temp @ 30 cm: 1.2C 8th
Max Soil Temp @ 30 cm: 5.4C 22nd
Mean Soil Temp @ 100 cm: 4.8C  
Min Soil Temp @ 100 cm: 4.0C 17th
Max Soil Temp @ 100 cm: 5.9C 1st
     
Mean 10 Min Wind >39 mph: 0.00 Days  
N: 7.13 Days  
NE: 3.92 Days  
E: 3.99 Days  
SE: 2.76 Days  
S: 0.35 Days  
SW: 1.06 Days  
W: 4.26 Days  
NW: 3.44 Days  
Calm: 4.09 Days  
Mean Wind: 3.4 mph  
Max Gust: 37 mph 16th
     
Mean Cloud Cover: 73%  
Mean RH @ 9am: 88%  
Rain Duration >0.1mm/hour: 50.0 Hours  
Frost Duration: 238.3 Hours  
Max Frost Duration in a Day: 24.0 Hours 7th
     
Mean Sea Temperature: 6.8C  
Normal for Month:    
Max Sea Temperature: 7.9C 1st
Min Sea Temperature: 6.1C 12th
     
Mean Pressure @ 9am: 1016.2 hPa (+0.9 hPa)
Mean Pressure: 1015.5 hPa (+0.2 hPa)
Max Pressure: 1041.6 hPa 26th
Min Pressure: 992.1 hPa 29th
     
Max Dewpoint: 9.2C 16th
Min Dewpoint: -13.0C 7th
Mean Dewpoint: -0.7C  
     
Max Humidity: 93% 15th
Min Humidity: 61% 30th
Mean Humidity: 86% (-0)

 

A very cold and often wet month with some snowfall though frequently quite sunny.

Both minimum and maximum temperatures were way below normal in what was a very cold month. There was a station record frost on the 7th of January with -10.7C. On that day the temperatures also failed to get above freezing which is the first 'ice day' recorded at this station.

Overall rainfall was rather wetter than normal with 118%. Even so, there were only 7 'rain' days as the rain tended to come in heavy downpours.
Snow lay on the ground for 6 days from the 6th to the 11th. There were 16 air frosts, this is another station record.
Sunshine levels were a little above average and there were 8 cloudless days.
Soil temperatures were well below normal throughout.
Winds were dominant from the north. Brrrrr!!!!
Rainfall duration for the whole month was a very low despite rainfall being above average.
Sea temperatures fell during the first two weeks then rose slightly thereafter.
Mean pressure was just a little higher than normal.
Dewpoints were well below normal due to frequent incursions of very dry and cold, Continental air.
The RH ended up being normal.
Weather Data for Otter Valley, Devon.  January 2010  
  Temp (oC) Hum (RH%) Dewpoint (oC) Wind (mph) Rain Pressure (hPa) Grass Sun  
  Min Max Ave Min Max Ave Min Max Ave Max Ave Run mm Min Max Ave Min Hours Observations
1 -1.9 3.1 0.6 71 86 79 -7.4 -1.3 -4.4 18 3.2 77 0.0 1002 1012 1007 -3.6 7.7 Sunny all day
2 -6.4 4.7 -0.9 85 91 88 -8.3 2.3 -3.0 7 0.2 6 0.0 1012 1020 1016 -8.8 7.5 Sunny all day
3 -5.6 3.0 -1.3 74 91 83 -7.6 -0.5 -4.1 21 3.6 87 0.0 1019 1023 1021 -9.5 7.2 Sunny all day
4 -7.2 2.1 -2.6 73 89 81 -9.4 -2.0 -5.7 10 1.1 26 0.0 1016 1024 1020 -11.3 7.7 Sunny all day
5 -8.9 1.7 -3.6 85 91 88 -11.1 0.0 -5.6 5 0.1 1 0.9 1000 1016 1008 -11.9 0.6 Sleet showers am, bright pm
6 -4.7 0.8 -2.0 80 91 86 -6.4 -1.0 -3.7 25 5.0 120 0.0 997 1009 1003 -6.2 0.2 Snow am, bright pm
7 -10.7 -0.7 -5.7 80 89 85 -13.0 -4.0 -8.5 23 1.7 42 0.0 1009 1018 1014 -15.8 7.8 Sunny all day.
8 -7.9 0.4 -3.8 77 90 84 -10.1 -3.2 -6.7 19 3.0 73 0.0 1018 1027 1022 -14.6 4.9 Sunny intervals all day.
9 -3.2 -0.2 -1.7 75 85 80 -5.7 -4.2 -5.0 21 7.1 170 0.0 1024 1027 1025 -6.2 7.5 Sunny all day.
10 -0.8 1.5 0.4 80 84 82 -5.4 -1.1 -3.3 21 5.1 124 0.0 1017 1024 1020 -4.5 0.0 Snow flurries am, cloudy pm
11 0.2 1.9 1.1 84 89 87 -2.0 -0.6 -1.3 16 2.5 61 0.0 1017 1019 1018 -1.2 0.0 Cloudy all day
12 1.3 2.8 2.1 78 90 84 -1.8 0.4 -0.7 34 8.7 208 11.1 997 1018 1007 0.1 0.2 Sunny ints am, rain pm
13 1.0 5.6 3.3 90 92 91 -0.7 4.2 1.8 21 2.1 50 6.1 996 1000 998 -0.6 0.1 Cloudy am, bright pm
14 0.7 3.9 2.3 91 92 92 -0.8 2.5 0.9 7 0.5 13 0.0 999 1012 1005 -1.5 0.0 Dull all day
15 1.1 9.0 5.1 89 93 91 -1.3 7.4 3.1 29 5.6 134 0.4 1012 1015 1014 0.3 0.3 Dull am, bright pm
16 5.8 10.7 8.3 87 93 90 3.9 9.2 6.6 37 9.1 219 33.4 1000 1012 1006 1.2 2.2 Rain am, sunny intervals pm
17 0.4 10.3 5.4 78 93 86 -1.0 7.2 3.1 16 1.6 39 0.0 1005 1023 1014 -2.3 7.4 Sunny all day
18 0.2 9.0 4.6 88 93 91 -1.5 7.7 3.1 8 0.5 12 0.0 1023 1026 1024 -1.9 2.4 Fog am, sunny intervals pm
19 6.1 7.6 6.9 82 93 88 3.0 5.2 4.1 30 7.4 178 0.0 1012 1025 1018 2.1 1.2 Sunny intervals all day
20 4.2 6.0 5.1 83 91 87 1.7 4.3 3.0 28 3.1 81 13.5 1006 1015 1011 0.3 0.2 Rain am, bright pm
21 3.0 8.9 6.0 90 92 91 1.2 7.0 4.1 26 5.2 125 4.6 1014 1019 1016 -0.1 0.0 Dull all day
22 7.7 10.4 9.1 86 93 90 2.2 8.8 5.5 28 5.1 122 14.4 1012 1019 1016 3.8 0.9 Rain am, sunny pm
23 -1.7 5.8 2.1 87 92 90 -3.3 4.0 0.4 12 1.1 26 0.0 1019 1023 1021 -4.1 1.4 Cloudy am, sunny ints pm
24 -0.7 6.4 2.9 78 92 85 -2.5 3.2 0.4 16 1.3 28 0.0 1023 1027 1025 -2.6 5.2 Sunny intervals all day
25 -1.7 4.7 1.5 81 92 87 -3.4 1.9 -0.8 14 2.4 57 0.0 1026 1036 1031 -3.2 1.7 Sunny intervals all day
26 1.2 2.8 2.0 75 88 82 -4.0 0.0 -2.0 14 2.0 47 0.0 1036 1042 1039 -0.8 0.3 Brief sunny intervals all day
27 -3.2 7.2 2.0 84 90 87 -5.5 5.2 -0.2 20 2.2 52 0.0 1023 1041 1032 -6.2 1.9 Sunny am, cloudy pm
28 3.6 7.9 5.8 77 91 84 0.9 5.9 3.4 20 4.3 103 0.0 1009 1023 1016 0.1 0.2 Cloudy am, sunny ints pm
29 3.1 7.3 5.2 67 92 80 -2.4 5.5 1.6 30 6.9 167 3.7 992 1009 1000 -0.3 1.8 Rain am, sunny intervals pm
30 -4.4 4.7 0.2 61 89 75 -6.7 -1.4 -4.1 15 2.4 57 0.0 999 1007 1003 -6.7 8.5 Sunny all day
31 -6.2 3.6 -1.3 83 91 87 -8.3 1.2 -3.6 9 0.6 12 0.0 1007 1010 1009 -8.5 1.7 Sunny intervals all day
-1.1 4.9 1.9 81 91 86 -3.8 2.5 -0.7 19 3.4 2514 88.1 1011 1020 1015 -4.0 88.48  

Graphs for January 2010

Figure 1. Temperature and Rainfall for January 2010.
Figure 2. Sunshine, air pressure and mean wind speed for January 2010.
Figure 3. Wind direction for January 2010.
Figure 4. Soil & sea surface temperature (SST) for Lyme Bay for January 2010.
Figure 5. Wind run, maximum gusts and mean pressure for January 2010.