| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
6.9 °C (+2.8) |
00:05 |
6.9 °C (+2.9) |
10.9 °C (+6.8), 2024 |
-2.4 °C (-6.5), 2012 |
| Maximum Temperature |
11.7 °C (+2.3) |
15:09 |
11.7 °C (+2.4) |
14.0 °C (+4.7), 2015 |
-0.1 °C (-9.4), 2010 |
| Mean Temperature |
10.2 °C (+2.6) |
|
10.2 °C (+2.7) |
12.3 °C, 2015 |
-0.7 °C, 2010 |
| Minimum Humidity |
83% |
00:04 |
83% |
91%, 2024 |
57%, 2010 |
| Maximum Humidity |
92% |
23:15 |
92% |
98%, 2012 |
80%, 2016 |
| Mean Humidity |
88% |
|
88% |
93%, 2024 |
71%, 2010 |
| Minimum Pressure |
997 hPa |
21:40 |
997 hPa |
1031 hPa, 2013 |
995 hPa, 2021 |
| Maximum Pressure |
1013 hPa |
00:00 |
1013 hPa |
1034 hPa, 2013 |
1008 hPa, 2021 |
| Mean Pressure |
1003 hPa |
|
1003 hPa |
1032 hPa, 2013 |
1000 hPa, 2021 |
| Mean Wind Speed |
11.3 mph (+6.2) |
|
11.3 mph (+6.2) |
11.3 mph, 2025 |
1.9 mph, 2013 |
| Maximum Wind Speed |
21.1 mph |
21:26 |
21.1 mph |
21.1 mph, 2025 |
6.2 mph, 2022 |
| Maximum Gust |
35.7 mph |
16:49 |
35.7 mph |
35.7 mph, 2025 |
8.7 mph, 2013 |
| Mean Wind Direction |
SW |
|
|
|
|
| Rainfall |
4.2 mm |
|
4.2 mm (228%) |
6.4 mm, 2018 |
|
| Maximum Hourly Rain |
1.2 mm |
23:47 |
|
2.6 mm, 2018 |
|
| Maximum 10-min Rain |
0.6 mm |
08:59 |
|
1.5 mm, 2021 |
|
| Maximum Rain Rate |
3.6 mm/h |
20:27 |
|
14 mm/h, 2021 |
|
| Minimum Dew Point |
4.2 °C |
00:05 |
4.2 °C |
9.7 °C, 2024 |
-8.0 °C, 2010 |
| Maximum Dew Point |
10.0 °C |
15:35 |
10.0 °C |
12.4 °C, 2024 |
-2.1 °C, 2010 |
| Mean Dew Point |
8.3 °C |
|
8.3 °C |
10.8 °C, 2024 |
-5.3 °C, 2010 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
* 6.1 °C * |
21:07 |
6.1 °C |
10.9 °C, 2024 |
-2.4 °C, 2012 |
| Day Maximum (09-21) |
11.7 °C |
15:09 |
11.7 °C |
14.0 °C, 2015 |
-0.1 °C, 2010 |
| Max 10m Temp Rise |
0.3 °C |
01:16 |
0.3 °C |
1.0 °C, 2015 |
0.1 °C, 2010 |
| Max 1hr Temp Rise |
1.0 °C |
01:23 |
1.0 °C |
2.6 °C, 2015 |
0.2 °C, 2014 |
| Max 1hr Hum Rise |
5% |
20:44 |
5% |
13%, 2021 |
2%, 2024 |
| Max 10m Temp Fall |
0.4 °C |
20:32 |
0.4 °C |
1.1 °C, 2021 |
0.1 °C, 2010 |
| Max 1hr Temp Fall |
1.1 °C |
21:04 |
1.1 °C |
2.6 °C, 2021 |
0.3 °C, 2010 |
| Max 1hr Hum Fall |
4% |
19:44 |
4% |
12%, 2012 |
3%, 2018 |
| Max 10m Wind Speed |
15.8 mph |
19:02 |
15.8 mph |
15.8 mph, 2025 |
4.7 mph, 2022 |
| Minimum Feels-like |
2.9 °C |
01:11 |
2.9 °C |
12.0 °C, 2024 |
-8.4 °C, 2010 |
| Maximum Feels-like |
12.9 °C |
15:09 |
12.9 °C |
15.8 °C, 2015 |
-3.3 °C, 2010 |
| Mean Feels-like |
9.5 °C |
|
9.5 °C |
13.5 °C, 2024 |
-6.1 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
24 hrs, 2010 |
0 hrs, 2009 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
4.8 °C (-0.5) |
4.8 °C (-0.4) |
8.2 °C (+2.9), 2021 |
0.9 °C (-4.4), 2010 |
| Humidity Range |
9% |
9% |
33%, 2010 |
5%, 2024 |
| Pressure Range |
16 hPa |
16 hPa |
16 hPa, 2025 |
2 hPa, 2022 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
0 [0%] | 0 hrs (0%) [0%] |
7 [96%], 2020 |
0 [0%], 2010 |
| Wet Hours |
7 [Mean rain rate: 0.6 mm/h] | 7 hrs (350%) [29%] |
7, 2011 |
0, 2012 |
| Cloud Cover |
unknown |
| Events |
None |
| 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 |
8.0 °C |