| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
8.1 °C (+0.3) |
02:29 |
8.7 °C (-0.1) |
14.2 °C (+6.4), 2017 |
3.0 °C (-4.8), 2010 |
| Maximum Temperature |
15.7 °C (+2.1) |
17:17 |
14.2 °C (-0.9) |
18.4 °C (+4.8), 2017 |
9.8 °C (-3.8), 2010 |
| Mean Temperature |
12.4 °C (+1.2) |
|
11.4 °C (-0.5) |
16.1 °C, 2017 |
6.1 °C, 2010 |
| Minimum Humidity |
83% |
11:56 |
74% |
89%, 2019 |
57%, 2011 |
| Maximum Humidity |
92% |
22:02 |
94% |
98%, 2009 |
79%, 2016 |
| Mean Humidity |
87% |
|
86% |
95%, 2012 |
72%, 2011 |
| Minimum Pressure |
995 hPa |
21:57 |
1006 hPa |
1026 hPa, 2018 |
993 hPa, 2011 |
| Maximum Pressure |
1011 hPa |
00:00 |
1014 hPa |
1031 hPa, 2018 |
1002 hPa, 2025 |
| Mean Pressure |
1003 hPa |
|
1010 hPa |
1029 hPa, 2018 |
998 hPa, 2011 |
| Mean Wind Speed |
6.7 mph (+2.6) |
|
3.6 mph (-0.5) |
7.4 mph, 2017 |
1.9 mph, 2023 |
| Maximum Wind Speed |
22.6 mph |
17:19 |
13.3 mph |
22.6 mph, 2020 |
9.9 mph, 2019 |
| Maximum Gust |
35.7 mph |
18:17 |
21.4 mph |
35.7 mph, 2020 |
13.7 mph, 2013 |
| Mean Wind Direction |
SSW |
|
|
|
|
| Rainfall |
7.6 mm |
|
147.9 mm (294%) |
9.5 mm, 2019 |
|
| Maximum Hourly Rain |
2.8 mm |
20:15 |
|
6.2 mm, 2019 |
|
| Maximum 10-min Rain |
1.4 mm |
22:10 |
|
1.4 mm, 2020 |
|
| Maximum Rain Rate |
24 mm/h |
22:09 |
|
24 mm/h, 2020 |
|
| Minimum Dew Point |
5.7 °C |
02:29 |
6.8 °C |
12.9 °C, 2017 |
1.6 °C, 2010 |
| Maximum Dew Point |
13.6 °C |
18:17 |
11.1 °C |
16.2 °C, 2009 |
5.0 °C, 2010 |
| Mean Dew Point |
10.3 °C |
|
9.2 °C |
14.2 °C, 2017 |
3.2 °C, 2010 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
8.1 °C |
02:29 |
9.2 °C |
14.2 °C, 2017 |
3.0 °C, 2010 |
| Day Maximum (09-21) |
15.7 °C |
17:17 |
14.2 °C |
18.4 °C, 2017 |
9.8 °C, 2010 |
| Max 10m Temp Rise |
0.4 °C |
11:02 |
0.4 °C |
0.9 °C, 2013 |
0.1 °C, 2019 |
| Max 1hr Temp Rise |
1.5 °C |
11:30 |
1.5 °C |
3.4 °C, 2013 |
0.6 °C, 2019 |
| Max 1hr Hum Rise |
8% |
14:53 |
7% |
11%, 2010 |
3%, 2014 |
| Max 10m Temp Fall |
0.6 °C |
22:20 |
0.4 °C |
0.9 °C, 2009 |
0.2 °C, 2012 |
| Max 1hr Temp Fall |
1.4 °C |
23:06 |
1.2 °C |
2.7 °C, 2015 |
0.5 °C, 2021 |
| Max 1hr Hum Fall |
6% |
11:23 |
8% |
19%, 2009 |
4%, 2015 |
| Max 10m Wind Speed |
18.0 mph |
17:25 |
9.0 mph |
18.0 mph, 2020 |
6.5 mph, 2018 |
| Minimum Feels-like |
6.5 °C |
01:57 |
7.4 °C |
16.9 °C, 2017 |
0.8 °C, 2025 |
| Maximum Feels-like |
18.6 °C |
17:25 |
15.8 °C |
22.6 °C, 2017 |
9.8 °C, 2010 |
| Mean Feels-like |
13.8 °C |
|
12.1 °C |
19.7 °C, 2017 |
5.0 °C, 2010 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
7.6 °C (+1.7) |
5.5 °C (-0.8) |
11.2 °C (+5.3), 2013 |
2.5 °C (-3.4), 2019 |
| Humidity Range |
9% |
20% |
31%, 2013 |
6%, 2019 |
| Pressure Range |
16 hPa |
8 hPa |
17 hPa, 2010 |
1 hPa, 2017 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
0 [0%] | 56 hrs (60%) [24%] |
9 [100%], 2024 |
0 [0%], 2014 |
| Wet Hours |
6 [Mean rain rate: 1.3 mm/h] | 109 hrs (286%) [19%] |
6, 2020 |
0, 2012 |
| Cloud Cover |
Overcast with periods of Mostly Cloudy |
| Events |
None |
| Comments |
pm- Rain spells |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
Yes - observations may be unreliable |
| Pond Temperature @ Hampstead Heath |
10.0 °C |