| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
12.2 °C (-1.9) |
02:02 |
13.9 °C (+0.1) |
17.5 °C (+3.4), 2010 |
9.8 °C (-4.3), 2020 |
| Maximum Temperature |
19.4 °C (-3.7) |
13:08 |
19.5 °C (-3.3) |
31.8 °C (+8.7), 2025 |
19.4 °C (-3.7), 2012 |
| Mean Temperature |
15.2 °C (-2.8) |
|
16.4 °C (-1.6) |
25.4 °C, 2025 |
15.2 °C, 2012 |
| Minimum Humidity |
44% |
14:32 |
61% |
82%, 2014 |
33%, 2015 |
| Maximum Humidity |
91% |
06:43 |
91% |
95%, 2009 |
65%, 2015 |
| Mean Humidity |
73% |
|
79% |
90%, 2014 |
48%, 2015 |
| Minimum Pressure |
1009 hPa |
16:11 |
1008 hPa |
1024 hPa, 2020 |
1005 hPa, 2016 |
| Maximum Pressure |
1011 hPa |
12:18 |
1012 hPa |
1029 hPa, 2020 |
1011 hPa, 2012 |
| Mean Pressure |
1010 hPa |
|
1010 hPa |
1027 hPa, 2020 |
1008 hPa, 2016 |
| Mean Wind Speed |
5.0 mph (+0.7) |
|
4.8 mph (+0.5) |
11.2 mph, 2016 |
2.1 mph, 2025 |
| Maximum Wind Speed |
15.4 mph |
13:56 |
12.1 mph |
23.7 mph, 2016 |
7.8 mph, 2014 |
| Maximum Gust |
20.6 mph |
13:41 |
16.5 mph |
38.7 mph, 2016 |
12.3 mph, 2011 |
| Mean Wind Direction |
W |
|
|
|
|
| Rainfall |
2.6 mm |
|
52.1 mm (319%) |
29.7 mm, 2017 |
|
| Maximum Hourly Rain |
1.4 mm |
22:47 |
|
6.6 mm, 2017 |
|
| Maximum 10-min Rain |
1.2 mm |
22:40 |
|
4.8 mm, 2017 |
|
| Maximum Rain Rate |
10 mm/h |
22:38 |
|
54 mm/h, 2016 |
|
| Minimum Dew Point |
6.4 °C |
14:32 |
10.5 °C |
14.3 °C, 2023 |
6.0 °C, 2013 |
| Maximum Dew Point |
12.5 °C |
08:41 |
14.6 °C |
16.8 °C, 2014 |
9.3 °C, 2013 |
| Mean Dew Point |
10.0 °C |
|
12.5 °C |
15.0 °C, 2023 |
7.7 °C, 2013 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
12.2 °C |
02:04 |
14.1 °C |
17.5 °C, 2010 |
9.8 °C, 2020 |
| Day Maximum (09-21) |
19.4 °C |
13:10 |
19.5 °C |
31.8 °C, 2025 |
19.4 °C, 2012 |
| Max 10m Temp Rise |
0.7 °C |
10:42 |
0.6 °C |
0.9 °C, 2013 |
0.3 °C, 2014 |
| Max 1hr Temp Rise |
2.2 °C |
08:42 |
1.9 °C |
4.0 °C, 2025 |
1.0 °C, 2014 |
| Max 1hr Hum Rise |
18% |
19:42 |
9% |
18%, 2012 |
4%, 2014 |
| Max 10m Temp Fall |
0.9 °C |
13:29 |
0.6 °C |
0.9 °C, 2009 |
0.3 °C, 2014 |
| Max 1hr Temp Fall |
3.0 °C |
19:18 |
1.6 °C |
3.0 °C, 2012 |
1.2 °C, 2009 |
| Max 1hr Hum Fall |
15% |
09:10 |
11% |
15%, 2012 |
4%, 2014 |
| Max 10m Wind Speed |
11.6 mph |
13:33 |
10.2 mph |
18.0 mph, 2016 |
5.2 mph, 2014 |
| Minimum Feels-like |
13.7 °C |
01:48 |
16.0 °C |
20.8 °C, 2023 |
8.3 °C, 2020 |
| Maximum Feels-like |
20.8 °C |
11:57 |
22.5 °C |
36.1 °C, 2025 |
20.8 °C, 2012 |
| Mean Feels-like |
16.5 °C |
|
19.0 °C |
29.4 °C, 2025 |
16.2 °C, 2020 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
7.2 °C (-1.8) |
5.7 °C (-3.4) |
15.6 °C (+6.6), 2025 |
5.0 °C (-4.0), 2017 |
| Humidity Range |
47% |
30% |
52%, 2011 |
12%, 2014 |
| Pressure Range |
2 hPa |
4 hPa |
6 hPa, 2023 |
1 hPa, 2010 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
6 [40%] | 29 hrs (40%) [17%] |
14.6 [98%], 2025 |
0 [0%], 2014 |
| Wet Hours |
2
[Mean rain rate: 1.3 mm/h] | 44 hrs (361%) [17%] |
8, 2017 |
0, 2010 |
| Cloud Cover |
Partly Cloudy with periods of Mostly Cloudy |
| Events |
None |
| Comments |
10 Light, 1530 Light, 19 Moderate, 2230 Heavy Showers |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
No |
| Pond Temperature @ Hampstead Heath |
0.0 °C |
