| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
7.5 °C (+0.6) |
01:47 |
6.4 °C (+0.4) |
11.4 °C (+4.5), 2010 |
2.9 °C (-4.0), 2009 |
| Maximum Temperature |
17.2 °C (+1.3) |
13:50 |
17.0 °C (+2.6) |
22.2 °C (+6.3), 2025 |
7.6 °C (-8.3), 2018 |
| Mean Temperature |
12.5 °C (+1.0) |
|
11.7 °C (+1.5) |
16.0 °C, 2025 |
6.7 °C, 2018 |
| Minimum Humidity |
37% |
13:18 |
42% |
81%, 2018 |
36%, 2013 |
| Maximum Humidity |
80% |
03:25 |
86% |
98%, 2012 |
78%, 2017 |
| Mean Humidity |
56% |
|
65% |
88%, 2012 |
52%, 2013 |
| Minimum Pressure |
1024 hPa |
19:02 |
1019 hPa |
1032 hPa, 2022 |
998 hPa, 2020 |
| Maximum Pressure |
1026 hPa |
11:54 |
1024 hPa |
1034 hPa, 2022 |
1006 hPa, 2020 |
| Mean Pressure |
1025 hPa |
|
1022 hPa |
1033 hPa, 2022 |
1003 hPa, 2020 |
| Mean Wind Speed |
9.8 mph (+4.9) |
|
5.6 mph (+0.7) |
9.8 mph, 2012 |
2.1 mph, 2014 |
| Maximum Wind Speed |
20.7 mph |
11:24 |
15.1 mph |
20.7 mph, 2026 |
7.8 mph, 2019 |
| Maximum Gust |
33.4 mph |
13:17 |
23.6 mph |
34.6 mph, 2012 |
11.5 mph, 2019 |
| Mean Wind Direction |
E |
|
|
|
|
| Rainfall |
0.0 mm |
|
2.3 mm (6%) |
16.9 mm, 2012 |
|
| Maximum Hourly Rain |
n/a |
|
|
2.7, 2010 |
|
| Maximum 10-min Rain |
n/a |
|
|
1.4, 2010 |
|
| Maximum Rain Rate |
n/a |
|
|
18, 2015 |
|
| Minimum Dew Point |
1.4 °C |
17:48 |
1.5 °C |
6.7 °C, 2014 |
-3.5 °C, 2015 |
| Maximum Dew Point |
6.0 °C |
08:08 |
7.9 °C |
13.1 °C, 2012 |
3.9 °C, 2021 |
| Mean Dew Point |
3.4 °C |
|
4.9 °C |
8.9 °C, 2010 |
0.2 °C, 2016 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
7.5 °C |
01:47 |
6.8 °C |
11.4 °C, 2010 |
2.9 °C, 2009 |
| Day Maximum (09-21) |
17.2 °C |
13:50 |
17.0 °C |
22.2 °C, 2025 |
7.6 °C, 2018 |
| Max 10m Temp Rise |
0.6 °C |
06:44 |
0.8 °C |
1.0 °C, 2017 |
0.2 °C, 2018 |
| Max 1hr Temp Rise |
2.3 °C |
08:31 |
2.7 °C |
4.1 °C, 2017 |
0.4 °C, 2018 |
| Max 1hr Hum Rise |
7% |
22:48 |
12% |
16%, 2016 |
3%, 2018 |
| Max 10m Temp Fall |
0.4 °C |
14:25 |
0.7 °C |
2.0 °C, 2016 |
0.3 °C, 2012 |
| Max 1hr Temp Fall |
1.2 °C |
21:18 |
2.1 °C |
3.0 °C, 2016 |
0.6 °C, 2018 |
| Max 1hr Hum Fall |
15% |
09:36 |
14% |
25%, 2012 |
4%, 2018 |
| Max 10m Wind Speed |
16.9 mph |
13:24 |
11.2 mph |
16.9 mph, 2026 |
5.7 mph, 2019 |
| Minimum Feels-like |
3.5 °C |
02:33 |
4.1 °C |
11.4 °C, 2010 |
-0.7 °C, 2021 |
| Maximum Feels-like |
17.2 °C |
13:50 |
17.4 °C |
22.9 °C, 2025 |
6.7 °C, 2018 |
| Mean Feels-like |
11.7 °C |
|
11.3 °C |
16.3 °C, 2025 |
3.8 °C, 2018 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
9.7 °C (+0.7) |
10.6 °C (+2.2) |
15.2 °C (+6.2), 2009 |
1.7 °C (-7.3), 2018 |
| Humidity Range |
43% |
44% |
55%, 2009 |
11%, 2018 |
| Pressure Range |
2 hPa |
5 hPa |
10 hPa, 2012 |
2 hPa, 2022 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
13.7 [103%] | 220 hrs (142%) [61%] |
13.7 [103%], 2026 |
0 [0%], 2018 |
| Wet Hours |
0 | 4 hrs (9%) [0.6%] |
13, 2012 |
0, 2009 |
| Cloud Cover |
unknown |
| Events |
Maximum possible sunshine |
| Comments |
data is awaiting quality control from site operator |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
Yes - observations may be unreliable |
| Pond Temperature @ Hampstead Heath |
12.4 °C |