| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
2.4 °C (-1.0) |
08:46 |
6.1 °C (+2.5) |
10.2 °C (+6.8), 2023 |
-2.8 °C (-6.2), 2010 |
| Maximum Temperature |
5.3 °C (-2.5) |
13:19 |
10.8 °C (+2.6) |
14.5 °C (+6.8), 2015 |
-0.2 °C (-8.0), 2010 |
| Mean Temperature |
3.6 °C (-1.7) |
|
8.7 °C (+2.5) |
12.1 °C, 2023 |
-1.5 °C, 2010 |
| Minimum Humidity |
54% |
13:13 |
79% |
93%, 2009 |
54%, 2025 |
| Maximum Humidity |
80% |
03:03 |
92% |
98%, 2009 |
80%, 2025 |
| Mean Humidity |
71% |
|
86% |
97%, 2009 |
71%, 2025 |
| Minimum Pressure |
1027 hPa |
19:11 |
1007 hPa |
1033 hPa, 2018 |
980 hPa, 2013 |
| Maximum Pressure |
1032 hPa |
00:22 |
1016 hPa |
1036 hPa, 2018 |
988 hPa, 2013 |
| Mean Pressure |
1029 hPa |
|
1012 hPa |
1035 hPa, 2018 |
984 hPa, 2013 |
| Mean Wind Speed |
10.0 mph (+4.9) |
|
6.3 mph (+1.2) |
10.9 mph, 2017 |
0.6 mph, 2018 |
| Maximum Wind Speed |
21.4 mph |
05:23 |
16.1 mph |
25.2 mph, 2017 |
5.4 mph, 2018 |
| Maximum Gust |
33.4 mph |
05:08 |
24.9 mph |
43.8 mph, 2017 |
8.1 mph, 2018 |
| Mean Wind Direction |
E |
|
|
|
|
| Rainfall |
0.0 mm |
|
60.6 mm (132%) |
12.6 mm, 2012 |
|
| Maximum Hourly Rain |
n/a |
|
|
4, 2017 |
|
| Maximum 10-min Rain |
n/a |
|
|
1.7, 2012 |
|
| Maximum Rain Rate |
n/a |
|
|
26, 2017 |
|
| Minimum Dew Point |
-3.3 °C |
13:13 |
4.1 °C |
8.5 °C, 2023 |
-4.8 °C, 2010 |
| Maximum Dew Point |
0.5 °C |
21:46 |
8.5 °C |
12.4 °C, 2015 |
-1.7 °C, 2010 |
| Mean Dew Point |
-1.2 °C |
|
6.5 °C |
10.7 °C, 2023 |
-2.9 °C, 2010 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
2.4 °C |
08:29 |
6.8 °C |
11.8 °C, 2023 |
-2.4 °C, 2010 |
| Day Maximum (09-21) |
5.3 °C |
13:16 |
10.7 °C |
14.3 °C, 2015 |
-0.7 °C, 2010 |
| Max 10m Temp Rise |
0.3 °C |
10:36 |
0.3 °C |
0.8 °C, 2013 |
0.1 °C, 2011 |
| Max 1hr Temp Rise |
1.0 °C |
11:24 |
1.1 °C |
1.8 °C, 2013 |
0.1 °C, 2021 |
| Max 1hr Hum Rise |
12% |
15:54 |
4% |
12%, 2025 |
1%, 2021 |
| Max 10m Temp Fall |
0.2 °C |
08:04 |
0.4 °C |
0.9 °C, 2017 |
0.2 °C, 2009 |
| Max 1hr Temp Fall |
0.7 °C |
15:40 |
1.0 °C |
3.4 °C, 2017 |
0.4 °C, 2015 |
| Max 1hr Hum Fall |
7% |
11:45 |
6% |
10%, 2014 |
1%, 2024 |
| Max 10m Wind Speed |
16.9 mph |
14:28 |
12.1 mph |
19.3 mph, 2017 |
3.6 mph, 2018 |
| Minimum Feels-like |
-4.4 °C |
05:08 |
3.7 °C |
10.8 °C, 2023 |
-6.6 °C, 2010 |
| Maximum Feels-like |
2.0 °C |
16:20 |
11.2 °C |
17.0 °C, 2015 |
-0.4 °C, 2010 |
| Mean Feels-like |
-1.3 °C |
|
7.7 °C |
13.7 °C, 2023 |
-3.3 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0.1 hrs |
24 hrs, 2010 |
0 hrs, 2009 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
2.9 °C (-1.5) |
4.7 °C (+0.1) |
8.6 °C (+4.2), 2015 |
1.7 °C (-2.7), 2024 |
| Humidity Range |
26% |
13% |
26%, 2025 |
3%, 2024 |
| Pressure Range |
4 hPa |
9 hPa |
24 hPa, 2017 |
3 hPa, 2016 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
6.9 [99%] | 55 hrs (104%) [31%] |
7 [100%], 2019 |
0 [0%], 2010 |
| Wet Hours |
0 | 62 hrs (124%) [10%] |
6, 2012 |
0, 2010 |
| 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 |
5.5 °C |