| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
7.3 °C (+4.3) |
04:17 |
5.9 °C (+2.9) |
7.3 °C (+4.3), 2026 |
-3.9 °C (-6.9), 2012 |
| Maximum Temperature |
10.6 °C (+2.8) |
15:32 |
9.3 °C (+1.4) |
11.4 °C (+3.6), 2011 |
2.1 °C (-5.7), 2012 |
| Mean Temperature |
8.9 °C (+3.5) |
|
7.4 °C (+2.1) |
9.0 °C, 2011 |
0.0 °C, 2012 |
| Minimum Humidity |
88% |
15:37 |
84% |
90%, 2010 |
54%, 2013 |
| Maximum Humidity |
94% |
11:50 |
95% |
98%, 2010 |
84%, 2011 |
| Mean Humidity |
91% |
|
91% |
96%, 2010 |
68%, 2013 |
| Minimum Pressure |
994 hPa |
00:02 |
991 hPa |
1039 hPa, 2023 |
977 hPa, 2014 |
| Maximum Pressure |
1002 hPa |
23:57 |
996 hPa |
1043 hPa, 2012 |
994 hPa, 2016 |
| Mean Pressure |
996 hPa |
|
993 hPa |
1040 hPa, 2023 |
989 hPa, 2014 |
| Mean Wind Speed |
5.2 mph (+0.1) |
|
5.5 mph (+0.4) |
11.5 mph, 2021 |
1.2 mph, 2023 |
| Maximum Wind Speed |
13.0 mph |
16:26 |
13.5 mph |
25.9 mph, 2016 |
8.5 mph, 2017 |
| Maximum Gust |
18.4 mph |
01:06 |
21.0 mph |
39.2 mph, 2019 |
11.5 mph, 2023 |
| Mean Wind Direction |
SW |
|
|
|
|
| Rainfall |
2.2 mm |
|
34.4 mm (306%) |
13.0 mm, 2016 |
|
| Maximum Hourly Rain |
1.2 mm |
09:03 |
|
10.7 mm, 2016 |
|
| Maximum 10-min Rain |
0.4 mm |
08:41 |
|
5.5 mm, 2016 |
|
| Maximum Rain Rate |
1.4 mm/h |
08:51 |
|
162 mm/h, 2016 |
|
| Minimum Dew Point |
6.1 °C |
04:16 |
4.5 °C |
6.1 °C, 2026 |
-10.4 °C, 2012 |
| Maximum Dew Point |
9.1 °C |
13:56 |
7.6 °C |
9.3 °C, 2014 |
-0.2 °C, 2018 |
| Mean Dew Point |
7.5 °C |
|
6.0 °C |
7.5 °C, 2026 |
-4.2 °C, 2012 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
7.3 °C |
04:17 |
6.1 °C |
8.7 °C, 2011 |
-2.4 °C, 2009 |
| Day Maximum (09-21) |
10.6 °C |
15:32 |
9.0 °C |
11.4 °C, 2011 |
0.9 °C, 2021 |
| Max 10m Temp Rise |
0.3 °C |
13:26 |
0.3 °C |
0.8 °C, 2023 |
0.2 °C, 2010 |
| Max 1hr Temp Rise |
0.8 °C |
13:52 |
0.8 °C |
2.5 °C, 2023 |
0.4 °C, 2010 |
| Max 1hr Hum Rise |
2% |
07:29 |
5% |
12%, 2016 |
2%, 2024 |
| Max 10m Temp Fall |
0.3 °C |
21:25 |
0.3 °C |
1.5 °C, 2014 |
0.2 °C, 2024 |
| Max 1hr Temp Fall |
0.7 °C |
22:15 |
0.8 °C |
4.5 °C, 2014 |
0.5 °C, 2024 |
| Max 1hr Hum Fall |
3% |
14:50 |
4% |
21%, 2011 |
3%, 2026 |
| Max 10m Wind Speed |
8.9 mph |
15:30 |
9.9 mph |
18.1 mph, 2016 |
4.6 mph, 2023 |
| Minimum Feels-like |
3.6 °C |
01:06 |
2.0 °C |
3.6 °C, 2026 |
-10.7 °C, 2012 |
| Maximum Feels-like |
11.4 °C |
15:18 |
9.1 °C |
11.8 °C, 2011 |
0.5 °C, 2021 |
| Mean Feels-like |
7.4 °C |
|
5.3 °C |
7.4 °C, 2026 |
-5.1 °C, 2021 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
11 hrs, 2009 |
0 hrs, 2010 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
3.3 °C (-1.5) |
3.4 °C (-1.5) |
9.3 °C (+4.5), 2020 |
2.0 °C (-2.8), 2025 |
| Humidity Range |
6% |
11% |
40%, 2012 |
6%, 2026 |
| Pressure Range |
8 hPa |
6 hPa |
19 hPa, 2014 |
2 hPa, 2023 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
0 [0%] | 2.6 hrs (14%) [4.4%] |
8 [94%], 2023 |
0 [0%], 2021 |
| Wet Hours |
4 [Mean rain rate: 0.6 mm/h] | 44 hrs (338%) [26%] |
10, 2025 |
, 2009 |
| 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 |
7.7 °C |