Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
Minimum Temperature |
6.8 °C (+3.8) |
05:00 |
7.0 °C (+4.0) |
10.3 °C (+7.3), 2017 |
-3.1 °C (-6.1), 2009 |
Maximum Temperature |
13.0 °C (+5.1) |
13:03 |
12.2 °C (+4.3) |
13.0 °C (+5.1), 2020 |
0.2 °C (-7.7), 2009 |
Mean Temperature |
10.2 °C (+4.5) |
|
10.0 °C (+4.2) |
10.9 °C, 2017 |
-1.4 °C, 2009 |
Minimum Humidity |
73% |
14:20 |
66% |
87%, 2009 |
41%, 2012 |
Maximum Humidity |
97% |
08:23 |
94% |
98%, 2011 |
65%, 2012 |
Mean Humidity |
84% |
|
81% |
93%, 2010 |
54%, 2012 |
Minimum Pressure |
1003 hPa |
06:43 |
1002 hPa |
1035 hPa, 2012 |
991 hPa, 2009 |
Maximum Pressure |
1011 hPa |
00:05 |
1011 hPa |
1038 hPa, 2012 |
1001 hPa, 2021 |
Mean Pressure |
1008 hPa |
|
1007 hPa |
1036 hPa, 2012 |
996 hPa, 2021 |
Mean Wind Speed |
7.2 mph (+2.1) |
|
8.2 mph (+3.2) |
10.1 mph, 2024 |
2.5 mph, 2025 |
Maximum Wind Speed |
20.7 mph |
11:22 |
21.9 mph |
21.5 mph, 2016 |
8.7 mph, 2015 |
Maximum Gust |
33.4 mph |
11:14 |
35.7 mph |
33.4 mph, 2020 |
10.9 mph, 2015 |
Mean Wind Direction |
SW |
|
|
|
|
Rainfall |
7.1 mm |
|
7.1 mm (229%) |
10.0 mm, 2009 |
|
Maximum Hourly Rain |
2.4 mm |
05:40 |
|
2.9 mm, 2021 |
|
Maximum 10-min Rain |
0.7 mm |
05:05 |
|
0.8 mm, 2021 |
|
Maximum Rain Rate |
18 mm/h |
03:46 |
|
18 mm/h, 2020 |
|
Minimum Dew Point |
4.1 °C |
01:01 |
3.6 °C |
6.9 °C, 2017 |
-11.5 °C, 2012 |
Maximum Dew Point |
10.3 °C |
09:00 |
10.1 °C |
10.3 °C, 2020 |
-7.9 °C, 2012 |
Mean Dew Point |
7.6 °C |
|
6.8 °C |
7.8 °C, 2017 |
-9.7 °C, 2012 |
Measure | Value | Time |
Month cumul. | Record High | Record Low |
Night Minimum (21-09) |
6.8 °C |
05:00 |
8.3 °C |
10.3 °C, 2017 |
-3.1 °C, 2009 |
Day Maximum (09-21) |
13.0 °C |
13:08 |
12.2 °C |
13.0 °C, 2020 |
0.2 °C, 2009 |
Max 10m Temp Rise |
0.4 °C |
07:25 |
0.3 °C |
0.9 °C, 2025 |
0.2 °C, 2016 |
Max 1hr Temp Rise |
2.0 °C |
08:13 |
1.4 °C |
3.0 °C, 2025 |
0.7 °C, 2016 |
Max 1hr Hum Rise |
5% |
02:50 |
5% |
8%, 2012 |
3%, 2019 |
Max 10m Temp Fall |
0.2 °C |
02:57 |
0.2 °C |
0.5 °C, 2010 |
0.2 °C, 2011 |
Max 1hr Temp Fall |
0.6 °C |
03:41 |
0.8 °C |
1.8 °C, 2010 |
0.6 °C, 2015 |
Max 1hr Hum Fall |
8% |
09:59 |
8% |
13%, 2016 |
3%, 2017 |
Max 10m Wind Speed |
15.1 mph |
11:29 |
16.8 mph |
16.0 mph, 2016 |
6.1 mph, 2015 |
Minimum Feels-like |
3.5 °C |
05:11 |
3.5 °C |
10.3 °C, 2017 |
-8.7 °C, 2012 |
Maximum Feels-like |
13.8 °C |
12:34 |
13.2 °C |
14.0 °C, 2024 |
-1.8 °C, 2012 |
Mean Feels-like |
10.1 °C |
|
9.5 °C |
11.3 °C, 2017 |
-5.6 °C, 2012 |
Air-frost Hrs |
0 hrs |
|
0 hrs |
18 hrs, 2012 |
0 hrs, 2010 |
Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
Temperature Range |
6.2 °C (+1.3) |
5.2 °C (+0.3) |
9.1 °C (+4.2), 2025 |
1.3 °C (-3.6), 2017 |
Humidity Range |
24% |
28% |
33%, 2013 |
7%, 2017 |
Pressure Range |
8 hPa |
9 hPa |
22 hPa, 2013 |
2 hPa, 2015 |
Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
Sun Hours |
0.4 [5%] | 4.9 hrs (95%) [30%] |
8.3 [101%], 2025 |
0 [0%], 2009 |
Wet Hours |
6 [Mean rain rate: 1.2 mm/h] | 6 hrs (167%) [13%] |
6, 2020 |
, 2009 |
Cloud Cover |
Overcast with periods of Mostly Cloudy |
Events |
None |
Comments |
02-08 Rain |
Extra Comments |
|
Issues |
None known |
Observer Absent? |
Yes - observations may be unreliable |
Pond Temperature @ Hampstead Heath |
5.0 °C |