| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
18.1 °C (+3.8) |
06:23 |
15.0 °C (+0.6) |
18.1 °C (+3.8), 2022 |
10.6 °C (-3.7), 2017 |
| Maximum Temperature |
34.9 °C (+12.3) |
17:03 |
29.2 °C (+6.2) |
34.9 °C (+12.3), 2026 |
17.0 °C (-5.6), 2019 |
| Mean Temperature |
27.5 °C (+8.0) |
|
22.4 °C (+3.4) |
27.5 °C, 2026 |
14.8 °C, 2010 |
| Minimum Humidity |
33% |
15:09 |
32% |
85%, 2020 |
29%, 2022 |
| Maximum Humidity |
69% |
06:43 |
77% |
95%, 2009 |
67%, 2016 |
| Mean Humidity |
47% |
|
53% |
91%, 2020 |
47%, 2026 |
| Minimum Pressure |
1016 hPa |
19:12 |
1017 hPa |
1023 hPa, 2016 |
1005 hPa, 2011 |
| Maximum Pressure |
1020 hPa |
00:02 |
1022 hPa |
1026 hPa, 2016 |
1009 hPa, 2015 |
| Mean Pressure |
1018 hPa |
|
1019 hPa |
1024 hPa, 2016 |
1006 hPa, 2015 |
| Mean Wind Speed |
2.3 mph (-1.7) |
|
3.9 mph (-0.1) |
5.9 mph, 2023 |
0.7 mph, 2024 |
| Maximum Wind Speed |
8.8 mph |
21:32 |
12.5 mph |
17.2 mph, 2023 |
7.1 mph, 2024 |
| Maximum Gust |
11.5 mph |
13:01 |
18.5 mph |
23.0 mph, 2019 |
10.4 mph, 2024 |
| Mean Wind Direction |
N |
|
|
|
|
| Rainfall |
0.0 mm |
|
0.0 mm (0%) |
13.4 mm, 2019 |
|
| Maximum Hourly Rain |
n/a |
|
|
4.8, 2019 |
|
| Maximum 10-min Rain |
n/a |
|
|
2.5, 2010 |
|
| Maximum Rain Rate |
n/a |
|
|
42, 2014 |
|
| Minimum Dew Point |
10.5 °C |
00:34 |
8.9 °C |
15.6 °C, 2020 |
5.7 °C, 2017 |
| Maximum Dew Point |
17.5 °C |
10:25 |
14.4 °C |
19.0 °C, 2024 |
9.8 °C, 2016 |
| Mean Dew Point |
14.7 °C |
|
11.6 °C |
17.0 °C, 2024 |
8.7 °C, 2016 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
18.1 °C |
06:24 |
15.1 °C |
18.1 °C, 2022 |
10.6 °C, 2017 |
| Day Maximum (09-21) |
34.9 °C |
17:04 |
29.2 °C |
34.9 °C, 2026 |
16.9 °C, 2019 |
| Max 10m Temp Rise |
1.0 °C |
07:17 |
0.9 °C |
1.1 °C, 2009 |
0.3 °C, 2020 |
| Max 1hr Temp Rise |
4.7 °C |
07:44 |
3.6 °C |
4.7 °C, 2026 |
0.9 °C, 2020 |
| Max 1hr Hum Rise |
12% |
21:51 |
11% |
16%, 2014 |
2%, 2020 |
| Max 10m Temp Fall |
0.8 °C |
21:45 |
0.8 °C |
1.3 °C, 2009 |
0.2 °C, 2020 |
| Max 1hr Temp Fall |
3.3 °C |
22:21 |
2.8 °C |
3.3 °C, 2022 |
0.6 °C, 2020 |
| Max 1hr Hum Fall |
9% |
07:40 |
13% |
19%, 2013 |
4%, 2020 |
| Max 10m Wind Speed |
7.0 mph |
22:08 |
9.0 mph |
11.4 mph, 2023 |
4.2 mph, 2020 |
| Minimum Feels-like |
20.3 °C |
06:21 |
16.5 °C |
22.1 °C, 2024 |
10.6 °C, 2017 |
| Maximum Feels-like |
40.0 °C |
16:14 |
31.7 °C |
40.0 °C, 2026 |
21.4 °C, 2010 |
| Mean Feels-like |
31.3 °C |
|
24.6 °C |
31.3 °C, 2026 |
17.5 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
| Minimum PM2.5 |
4 |
21:35 |
3 |
4, 2026 |
0, 2021 |
| Maximum PM2.5 |
25 |
12:55 |
13 |
25, 2026 |
25, 2026 |
| Mean PM2.5 |
12 |
|
6 |
12, 2026 |
12, 2026 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
16.8 °C (+8.5) |
14.2 °C (+5.6) |
16.8 °C (+8.5), 2026 |
2.5 °C (-5.8), 2020 |
| Humidity Range |
36% |
46% |
47%, 2022 |
9%, 2020 |
| Pressure Range |
5 hPa |
5 hPa |
10 hPa, 2019 |
2 hPa, 2012 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
13 [97%] | 168 hrs (194%) [88%] |
13 [97%], 2026 |
0 [0%], 2020 |
| Wet Hours |
0 | 0 hrs (0%) [0%] |
10, 2019 |
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 |
22.5 °C |