July 2011

A south Devon beach near East Prawle on a hot July day.
A south Devon beach near East Prawle on a hot July day.
Summary for  July 2011
Mean Max: 21.7ºC (+0.2ºC)
Mean Min: 11.3ºC (-1.0ºC)
Mean: 16.5ºC (-0.4ºC)
     
High Max: 26.3ºC 25th
Low Max: 14.0ºC 18th
High Min: 15.4ºC 28th
Low Min: 5.8ºC 1st
Mean Grass Min: 9.5ºC  
Grass Min: 5.6ºC 1st
     
Rain Total (gauge): 23.0 mm (56%)
Rain Total (tipping bucket): 23.1 mm (57%)
Rain Days >0.2 mm: 10 Days  
Rain Days >1.0 mm: 7 Days  
Max 24 hrs: 5.1 mm 8th
Days without any rain: 21  
     
Air Frost: 0 Days  
Ground Frost: 0 Days  
Snow Falling: 0 Days  
Snow (50%) @ 9am: 0 Days  
Thunder Heard: 0 Days  
Hail <5 mm: 0 Days  
Hail >5 mm: 0 Days  
Fog @ 9am: 0 Days  
     
Total Monthly Sunshine: 170h:16m  
Total Monthly Sunshine: 170.3 Hours (81%)
Most Sunshine in a Day: 15.8 3rd 
Average Daily Sunshine: 05h:29m  
Sunless Days: 1 Day  
Cloudless Days: 4 Days  
Total Possible Sunshine: 495h:38m  
Percentage of Total Sun: 34%  
Maximum UV Index: 9 6th
Average UV Index: 6.5  
     
Mean Soil Temp @ 30 cm: 17.8ºC  
Min Soil Temp @ 30 cm: 16.8ºC 19th
Max Soil Temp @ 30 cm: 18.9ºC 28th
Mean Soil Temp @ 100 cm: 17.5ºC  
Min Soil Temp @ 100 cm: 17.0ºC 1st
Max Soil Temp @ 100 cm: 18.3ºC 30th
     
Mean 10 Min Wind >39 mph: 0.04 Days  
N: 3.33 Days  
NE: 1.65 Days  
E: 1.17 Days  
SE: 4.22 Days  
S: 4.34 Days  
SW: 2.20 Days  
W: 3.81 Days  
NW: 3.27 Days  
Calm: 7.01 Days  
Wind Chill Low: 5.2ºC 1st
Mean Wind: 3.6 mph  
Max Gust: 29 mph 17th
     
Mean Cloud Cover: 68%  
Mean RH @ 9am: 82%  
Rain Duration >0.1mm/hour: 17.3 Hours  
Frost Duration: 0.0 Hours  
Max Frost Duration in a Day: 0.0 Hours 1st
     
Mean Sea Temperature: 17.0ºC (-0.5ºC)
Normal for Month: 17.5ºC  
Max Sea Temperature: 18.3ºC 28th
Min Sea Temperature: 15.8ºC 1st
     
Mean Pressure @ 9am: 1013.0 hPa (-4.8 hPa)
Mean Pressure: 1013.2 hPa (-4.6 hPa)
Max Pressure: 1027.7 hPa 1st
Min Pressure: 993.3 hPa 17th
     
Max Dewpoint: 16.1ºC 29th
Min Dewpoint: 2.4ºC 1st
Mean Dewpoint: 10.3ºC  
     
Max Humidity: 92% 19th
Min Humidity: 35% 26th
Mean Humidity: 72% (-4)

 

July continued in the same way as June with generally unsettled, of then cloudy weather though there were quite a few warm and sunny days as well.

The temperatures for July were around the average, though there were quite a few unusually cool nights early/mid month. The last week of the month was settled, warm and fairly sunny.
Rainfall was well below the average and is the driest July recorded since before 2005.
As would be expected in a summer month, there were no air or grass frosts. Unusually no thunder was heard.
Sunshine levels were rather below the long term average of around 220 hours. This was the dullest June since only 2009, showing just how dull this month has been since 2007.
Soil temperatures were slightly above normal at the beginning of the month and continued this way right through.
Wind were dominant from the south or south east sectors, showing the influence of the sea breeze that blows from these directions.
Rainfall duration was just 17.3 hours, most of which was in the form of drizzle or patchy light rain.
Sea surface temperatures were slightly below normal at the beginning of the month and generally stayed that way until the last week. They ended the month rather above normal.
Mean pressure was a little below the average for July and indicative of the unsettled nature of this month.
Dewpoints were a little below average.
The RH ended up being below normal due to regular incursions of fairly dry, cool air.
Weather Data for Otter Valley, Devon.  July 2011  
  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 5.8 21.7 13.8 52 91 72 2.4 11.2 6.8 14 1.9 46 0.0 1023 1028 1026 5.6 7.9 Sunny intervals all day
2 7.1 24.8 16.0 38 90 64 4.1 11.6 7.9 16 2.4 57 0.0 1017 1028 1022 7.1 13.8 Sunny all day
3 7.4 25.4 16.4 36 88 62 3.7 10.4 7.1 16 2.9 70 0.0 1016 1018 1017 6.5 15.8 Sunny all day
4 8.7 24.4 16.6 43 86 65 4.6 12.2 8.4 21 4.4 106 0.0 1015 1017 1016 8.1 7.2 Sunny am, cloudy pm
5 14.6 20.1 17.4 56 86 71 7.0 15.0 11.0 21 5.4 130 0.0 1007 1015 1011 12.3 3.0 Sunny intervals all day
6 11.3 19.2 15.3 55 89 72 8.0 11.5 9.8 26 5.5 132 4.0 1001 1007 1004 9.5 4.0 Sunny ints am, showers pm
7 11.1 20.1 15.6 55 89 72 8.6 12.2 10.4 28 6.0 145 2.9 1000 1002 1001 9.6 3.0 Sunny intervals all day
8 12.3 18.9 15.6 66 90 78 8.7 12.6 10.7 26 6.6 158 5.1 1000 1005 1002 11.6 4.0 Sunny intervals all day
9 10.8 20.1 15.5 56 89 73 7.8 11.9 9.9 19 4.1 100 0.0 1005 1015 1010 8.9 3.0 Sunny intervals all day
10 12.2 21.1 16.7 56 88 72 8.4 12.4 10.4 14 1.8 44 0.0 1015 1019 1017 9.3 13.0 Sunny intervals all day
11 8.0 23.5 15.8 51 91 71 5.0 14.2 9.6 9 1.3 32 0.0 1018 1021 1019 6.4 7.0 Sunny intervals all day
12 14.6 22.4 18.5 57 79 68 9.6 13.9 11.8 19 4.6 110 0.0 1016 1019 1018 12.7 5.0 Sunny intervals all day
13 13.1 23.0 18.1 45 78 62 8.3 11.4 9.9 13 3.3 79 0.0 1018 1020 1019 9.1 6.0 Sunny intervals all day
14 7.2 26.1 16.7 38 91 65 4.2 12.6 8.4 15 2.2 54 0.0 1018 1021 1019 5.8 13.0 Sunny all day
15 9.5 21.2 15.4 61 90 76 5.8 13.9 9.9 19 3.9 94 0.0 1012 1020 1016 7.7 6.0 Sunny am, cloudy pm
16 13.9 18.8 16.4 57 91 74 8.9 13.8 11.4 24 6.2 149 2.2 997 1013 1005 10.3 2.6 Rain am, sunny ints pm
17 12.6 18.4 15.5 66 89 78 8.4 12.2 10.3 29 8.1 194 1.8 993 998 996 10.9 0.7 Showers am, sunny ints pm
18 12.3 14.0 13.2 82 90 86 9.7 11.4 10.6 18 2.9 70 2.6 998 1000 999 11.1 0.0 Cloudy all day
19 11.3 20.1 15.7 65 92 79 9.0 13.1 11.1 0 0.0 0 0.7 1000 1009 1004 9.9 2.3 Sunny intervals all day
20 12.7 17.2 15.0 73 89 81 9.4 12.7 11.1 0 0.0 0 2.6 1008 1010 1009 12.3 0.0 Cloudy am, sunny ints pm
21 10.1 22.4 16.3 53 91 72 7.5 12.5 10.0 14 1.7 40 0.0 1009 1015 1012 7.9 6.4 Sunny intervals all day
22 12.8 19.6 16.2 59 87 73 9.9 13.1 11.5 16 2.2 54 0.7 1015 1018 1016 7.2 4.1 Sunny intervals all day
23 8.4 21.2 14.8 47 91 69 5.2 10.3 7.8 18 4.6 111 0.0 1014 1017 1015 6.5 12.8 Sunny all day
24 7.7 19.1 13.4 67 92 80 4.8 14.2 9.5 18 3.6 79 0.7 1010 1015 1013 6.4 4.3 Sunny intervals all day
25 12.6 26.3 19.5 41 91 66 9.8 14.0 11.9 17 3.7 87 0.0 1009 1011 1010 10.6 4.0 Sunny intervals all day
26 13.1 26.1 19.6 35 79 57 7.9 11.9 9.9 13 2.9 70 0.0 1011 1017 1014 10.5 4.3 Cloudy am, sunny pm
27 13.8 25.1 19.5 52 86 69 7.6 15.2 11.4 12 1.7 40 0.0 1017 1021 1019 10.5 3.8 Sunny intervals all day
28 15.4 24.9 20.2 47 85 66 11.7 14.6 13.2 13 1.7 41 0.0 1021 1022 1021 14.9 4.1 Sunny intervals all day
29 15.1 23.6 19.4 62 88 75 11.5 16.1 13.8 11 2.1 52 0.0 1021 1023 1022 13.8 0.5 Cloudy am, sunny ints pm
30 12.7 22.2 17.5 62 91 77 9.6 14.4 12.0 16 3.1 74 0.0 1019 1022 1020 11.0 5.2 Sunny intervals all day
31 13.3 23.2 18.3 65 91 78 9.6 16.1 12.9 16 3.3 64 0.0 1012 1019 1016 10.2 3.5 Sunny intervals all day
11.3 21.7 16.5 55 88 72 7.6 13.0 10.3 18 3.6 2476 23.1 1011 1015 1013 9.5 170.3  

Graphs for July 2011
Figure 1. Temperature and Rainfall for July 2011.
Figure 2. Sunshine, air pressure and mean wind speed for July 2011.
Figure 3. Wind direction for July 2011.
Figure 4. Soil & sea surface temperature (SST) for Lyme Bay for July 2011.
Figure 5. Wind run, maximum gusts and mean pressure for July 2011.