| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
6.0 °C (+2.6) |
23:58 |
6.5 °C (+2.8) |
13.2 °C (+9.8), 2015 |
-5.3 °C (-8.7), 2010 |
| Maximum Temperature |
10.9 °C (+3.2) |
00:01 |
11.6 °C (+3.2) |
16.0 °C (+8.3), 2015 |
0.1 °C (-7.6), 2010 |
| Mean Temperature |
8.4 °C (+2.9) |
|
9.3 °C (+3.0) |
14.8 °C, 2015 |
-2.6 °C, 2010 |
| Minimum Humidity |
74% |
14:27 |
79% |
93%, 2021 |
57%, 2014 |
| Maximum Humidity |
91% |
23:35 |
92% |
98%, 2012 |
82%, 2016 |
| Mean Humidity |
84% |
|
87% |
96%, 2021 |
76%, 2014 |
| Minimum Pressure |
1007 hPa |
00:01 |
1005 hPa |
1034 hPa, 2017 |
988 hPa, 2019 |
| Maximum Pressure |
1019 hPa |
19:43 |
1015 hPa |
1039 hPa, 2021 |
1000 hPa, 2010 |
| Mean Pressure |
1016 hPa |
|
1010 hPa |
1035 hPa, 2021 |
996 hPa, 2010 |
| Mean Wind Speed |
5.0 mph (-0.1) |
|
6.2 mph (+1.1) |
11.9 mph, 2022 |
0.5 mph, 2016 |
| Maximum Wind Speed |
12.7 mph |
13:55 |
16.4 mph |
21.7 mph, 2022 |
4.7 mph, 2016 |
| Maximum Gust |
19.6 mph |
13:56 |
25.4 mph |
34.6 mph, 2022 |
6.3 mph, 2016 |
| Mean Wind Direction |
W |
|
|
|
|
| Rainfall |
1.0 mm |
|
55.6 mm (159%) |
11.0 mm, 2023 |
|
| Maximum Hourly Rain |
1.0 mm |
01:01 |
|
3.7 mm, 2013 |
|
| Maximum 10-min Rain |
1.0 mm |
00:11 |
|
2.0 mm, 2014 |
|
| Maximum Rain Rate |
7 mm/h |
00:11 |
|
30 mm/h, 2014 |
|
| Minimum Dew Point |
4.6 °C |
23:58 |
4.7 °C |
9.4 °C, 2015 |
-8.0 °C, 2010 |
| Maximum Dew Point |
9.3 °C |
00:22 |
9.3 °C |
13.5 °C, 2015 |
-1.6 °C, 2010 |
| Mean Dew Point |
5.8 °C |
|
7.3 °C |
11.2 °C, 2015 |
-4.4 °C, 2010 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
* 7.0 °C * |
08:28 |
7.3 °C |
12.6 °C, 2015 |
-4.3 °C, 2010 |
| Day Maximum (09-21) |
* 10.4 °C * |
13:57 |
11.5 °C |
16.0 °C, 2015 |
0.1 °C, 2010 |
| Max 10m Temp Rise |
0.4 °C |
11:35 |
0.4 °C |
0.4 °C, 2025 |
0.1 °C, 2023 |
| Max 1hr Temp Rise |
1.3 °C |
11:43 |
1.2 °C |
1.4 °C, 2017 |
0.1 °C, 2023 |
| Max 1hr Hum Rise |
4% |
04:22 |
4% |
9%, 2013 |
1%, 2021 |
| Max 10m Temp Fall |
0.3 °C |
19:24 |
0.4 °C |
1.7 °C, 2024 |
0.2 °C, 2015 |
| Max 1hr Temp Fall |
0.9 °C |
01:37 |
1.1 °C |
5.3 °C, 2024 |
0.4 °C, 2016 |
| Max 1hr Hum Fall |
8% |
01:28 |
6% |
17%, 2014 |
2%, 2016 |
| Max 10m Wind Speed |
8.9 mph |
11:39 |
12.1 mph |
16.6 mph, 2022 |
2.5 mph, 2016 |
| Minimum Feels-like |
3.0 °C |
08:31 |
4.6 °C |
14.9 °C, 2015 |
-9.8 °C, 2010 |
| Maximum Feels-like |
11.9 °C |
00:05 |
12.3 °C |
18.6 °C, 2015 |
0.0 °C, 2010 |
| Mean Feels-like |
6.7 °C |
|
8.8 °C |
16.7 °C, 2015 |
-5.9 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0.1 hrs |
23 hrs, 2010 |
0 hrs, 2012 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
4.9 °C (+0.7) |
5.1 °C (+0.5) |
8.9 °C (+4.7), 2024 |
1.9 °C (-2.3), 2016 |
| Humidity Range |
17% |
13% |
34%, 2014 |
3%, 2016 |
| Pressure Range |
12 hPa |
10 hPa |
26 hPa, 2024 |
2 hPa, 2017 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
5.8 [83%] | 38 hrs (96%) [28%] |
6.5 [93%], 2009 |
0 [0%], 2010 |
| Wet Hours |
1 [Mean rain rate: 1.0 mm/h] | 54 hrs (142%) [12%] |
11, 2023 |
0, 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 |
7.2 °C |