| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
6.5 °C (+3.6) |
00:01 |
4.9 °C (+1.8) |
6.8 °C (+3.9), 2019 |
-1.8 °C (-4.7), 2010 |
| Maximum Temperature |
10.1 °C (+2.3) |
13:24 |
9.4 °C (+1.6) |
12.4 °C (+4.6), 2024 |
0.4 °C (-7.4), 2017 |
| Mean Temperature |
8.4 °C (+3.0) |
|
7.3 °C (+1.7) |
9.6 °C, 2016 |
-0.4 °C, 2017 |
| Minimum Humidity |
81% |
13:30 |
79% |
84%, 2021 |
58%, 2015 |
| Maximum Humidity |
93% |
02:45 |
93% |
97%, 2011 |
82%, 2017 |
| Mean Humidity |
90% |
|
87% |
92%, 2011 |
76%, 2017 |
| Minimum Pressure |
1006 hPa |
20:20 |
1018 hPa |
1038 hPa, 2010 |
978 hPa, 2025 |
| Maximum Pressure |
1015 hPa |
00:00 |
1029 hPa |
1042 hPa, 2010 |
1007 hPa, 2009 |
| Mean Pressure |
1010 hPa |
|
1024 hPa |
1040 hPa, 2010 |
996 hPa, 2025 |
| Mean Wind Speed |
6.4 mph (+1.2) |
|
5.7 mph (+0.5) |
10.8 mph, 2016 |
2.2 mph, 2018 |
| Maximum Wind Speed |
15.1 mph |
14:02 |
14.8 mph |
23.2 mph, 2016 |
7.6 mph, 2018 |
| Maximum Gust |
25.3 mph |
14:12 |
23.5 mph |
38.4 mph, 2016 |
11.0 mph, 2009 |
| Mean Wind Direction |
SSW |
|
|
|
|
| Rainfall |
2.3 mm |
|
33.1 mm (67%) |
9.2 mm, 2025 |
|
| Maximum Hourly Rain |
0.9 mm |
16:28 |
|
5.3 mm, 2019 |
|
| Maximum 10-min Rain |
0.5 mm |
15:57 |
|
2.9 mm, 2019 |
|
| Maximum Rain Rate |
18 mm/h |
17:25 |
|
53 mm/h, 2019 |
|
| Minimum Dew Point |
5.3 °C |
00:01 |
3.0 °C |
5.4 °C, 2019 |
-5.2 °C, 2017 |
| Maximum Dew Point |
8.2 °C |
19:15 |
7.3 °C |
11.4 °C, 2024 |
-2.5 °C, 2017 |
| Mean Dew Point |
6.8 °C |
|
5.2 °C |
7.3 °C, 2016 |
-4.2 °C, 2017 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
* 5.8 °C * |
21:04 |
5.5 °C |
7.7 °C, 2015 |
-0.3 °C, 2021 |
| Day Maximum (09-21) |
10.1 °C |
13:26 |
9.1 °C |
11.5 °C, 2016 |
0.4 °C, 2017 |
| Max 10m Temp Rise |
0.3 °C |
10:29 |
0.3 °C |
0.5 °C, 2018 |
0.1 °C, 2011 |
| Max 1hr Temp Rise |
0.8 °C |
11:27 |
1.0 °C |
2.1 °C, 2025 |
0.4 °C, 2017 |
| Max 1hr Hum Rise |
6% |
14:38 |
5% |
13%, 2012 |
2%, 2017 |
| Max 10m Temp Fall |
0.2 °C |
14:46 |
0.4 °C |
0.8 °C, 2012 |
0.2 °C, 2010 |
| Max 1hr Temp Fall |
0.6 °C |
15:22 |
1.1 °C |
2.6 °C, 2012 |
0.6 °C, 2015 |
| Max 1hr Hum Fall |
4% |
11:18 |
5% |
19%, 2014 |
2%, 2017 |
| Max 10m Wind Speed |
11.2 mph |
14:48 |
11.0 mph |
18.1 mph, 2016 |
5.3 mph, 2018 |
| Minimum Feels-like |
3.3 °C |
05:26 |
1.3 °C |
3.6 °C, 2016 |
-6.4 °C, 2017 |
| Maximum Feels-like |
10.2 °C |
13:07 |
9.8 °C |
14.3 °C, 2024 |
0.0 °C, 2017 |
| Mean Feels-like |
6.1 °C |
|
5.8 °C |
9.0 °C, 2016 |
-3.8 °C, 2017 |
| Air-frost Hrs |
0 hrs |
|
0.3 hrs |
12 hrs, 2017 |
0 hrs, 2011 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
3.6 °C (-1.2) |
4.5 °C (-0.3) |
9.4 °C (+4.6), 2025 |
2.1 °C (-2.7), 2017 |
| Humidity Range |
12% |
14% |
35%, 2015 |
10%, 2023 |
| Pressure Range |
9 hPa |
11 hPa |
30 hPa, 2025 |
3 hPa, 2023 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
0.1 [1%] | 54 hrs (94%) [28%] |
7.9 [100%], 2024 |
0 [0%], 2011 |
| Wet Hours |
4 [Mean rain rate: 0.6 mm/h] | 50 hrs (88%) [7.9%] |
7, 2025 |
, 2009 |
| Cloud Cover |
Overcast or Mostly Cloudy |
| Events |
None |
| Comments |
pm Rain |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
Yes - observations may be unreliable |
| Pond Temperature @ Hampstead Heath |
5.0 °C |