| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
6.6 °C (+3.4) |
22:37 |
5.8 °C (+2.7) |
9.6 °C (+6.4), 2023 |
-4.2 °C (-7.3), 2010 |
| Maximum Temperature |
11.3 °C (+3.5) |
05:45 |
10.7 °C (+2.8) |
13.2 °C (+5.4), 2023 |
1.0 °C (-6.8), 2010 |
| Mean Temperature |
8.9 °C (+3.5) |
|
8.2 °C (+2.8) |
11.3 °C, 2023 |
-1.5 °C, 2010 |
| Minimum Humidity |
56% |
14:01 |
66% |
94%, 2025 |
46%, 2009 |
| Maximum Humidity |
85% |
06:36 |
91% |
99%, 2025 |
81%, 2017 |
| Mean Humidity |
70% |
|
80% |
97%, 2025 |
66%, 2009 |
| Minimum Pressure |
997 hPa |
05:33 |
999 hPa |
1038 hPa, 2019 |
980 hPa, 2025 |
| Maximum Pressure |
1018 hPa |
23:32 |
1014 hPa |
1041 hPa, 2019 |
989 hPa, 2016 |
| Mean Pressure |
1008 hPa |
|
1006 hPa |
1039 hPa, 2019 |
984 hPa, 2016 |
| Mean Wind Speed |
11.1 mph (+5.9) |
|
8.9 mph (+3.7) |
11.1 mph, 2012 |
0.8 mph, 2017 |
| Maximum Wind Speed |
25.5 mph |
|
21.7 mph |
25.5 mph, 2012 |
5.1 mph, 2017 |
| Maximum Gust |
44.0 mph |
05:25 |
31.6 mph |
44.0 mph, 2012 |
7.3 mph, 2017 |
| Mean Wind Direction |
WNW |
|
|
|
|
| Rainfall |
4.6 mm |
|
26.4 mm (277%) |
31.0 mm, 2025 |
|
| Maximum Hourly Rain |
2.2 mm |
06:25 |
|
4.2 mm, 2025 |
|
| Maximum 10-min Rain |
1.4 mm |
06:25 |
|
1.6 mm, 2025 |
|
| Maximum Rain Rate |
20 mm/h |
06:26 |
|
24 mm/h, 2025 |
|
| Minimum Dew Point |
0.3 °C |
15:53 |
1.4 °C |
7.7 °C, 2023 |
-5.2 °C, 2010 |
| Maximum Dew Point |
7.9 °C |
06:30 |
8.6 °C |
11.8 °C, 2025 |
-1.0 °C, 2010 |
| Mean Dew Point |
3.6 °C |
|
4.8 °C |
9.1 °C, 2023 |
-3.3 °C, 2010 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
* 8.3 °C * |
21:00 |
6.8 °C |
9.6 °C, 2023 |
-4.2 °C, 2010 |
| Day Maximum (09-21) |
* 9.6 °C * |
12:15 |
9.9 °C |
13.2 °C, 2023 |
1.0 °C, 2010 |
| Max 10m Temp Rise |
0.3 °C |
09:22 |
0.3 °C |
2.6 °C, 2025 |
0.2 °C, 2013 |
| Max 1hr Temp Rise |
1.0 °C |
10:59 |
0.9 °C |
7.6 °C, 2025 |
0.5 °C, 2019 |
| Max 1hr Hum Rise |
11% |
06:37 |
8% |
11%, 2012 |
1%, 2015 |
| Max 10m Temp Fall |
0.9 °C |
08:08 |
0.7 °C |
0.9 °C, 2012 |
0.1 °C, 2014 |
| Max 1hr Temp Fall |
2.1 °C |
08:43 |
1.9 °C |
2.1 °C, 2012 |
0.3 °C, 2015 |
| Max 1hr Hum Fall |
16% |
09:38 |
11% |
16%, 2012 |
1%, 2025 |
| Max 10m Wind Speed |
17.1 mph |
14:02 |
13.7 mph |
17.1 mph, 2012 |
3.4 mph, 2017 |
| Minimum Feels-like |
2.3 °C |
21:11 |
1.6 °C |
7.0 °C, 2023 |
-8.9 °C, 2010 |
| Maximum Feels-like |
11.3 °C |
05:50 |
10.6 °C |
14.7 °C, 2023 |
1.0 °C, 2010 |
| Mean Feels-like |
6.8 °C |
|
6.4 °C |
11.9 °C, 2023 |
-3.6 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
13 hrs, 2010 |
0 hrs, 2011 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
4.7 °C (+0.0) |
4.8 °C (+0.2) |
11.9 °C (+7.2), 2025 |
2.0 °C (-2.7), 2020 |
| Humidity Range |
29% |
25% |
40%, 2009 |
5%, 2016 |
| Pressure Range |
21 hPa |
15 hPa |
22 hPa, 2025 |
2 hPa, 2021 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
4 [56%] | 12 hrs (115%) [34%] |
7.2 [101%], 2017 |
0 [0%], 2013 |
| Wet Hours |
2
[Mean rain rate: 2.3 mm/h] | 18 hrs (167%) [15%] |
19, 2025 |
, 2009 |
| Cloud Cover |
Sunny with periods of Mostly Cloudy |
| Events |
None |
| Comments |
06, 08, 10 Heavy; 12, 13 Light Showers |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
No |
| Pond Temperature @ Hampstead Heath |
0.0 °C |
