Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
Minimum Temperature |
15.0 °C (+0.3) |
23:59 |
13.4 °C (-0.8) |
19.4 °C (+4.7), 2019 |
10.4 °C (-4.3), 2011 |
Maximum Temperature |
21.4 °C (-1.9) |
13:21 |
22.0 °C (-1.1) |
36.8 °C (+13.5), 2019 |
20.2 °C (-3.1), 2023 |
Mean Temperature |
18.0 °C (-0.8) |
|
17.7 °C (-0.9) |
28.4 °C, 2019 |
15.5 °C, 2015 |
Minimum Humidity |
74% |
14:14 |
54% |
83%, 2024 |
32%, 2012 |
Maximum Humidity |
92% |
23:17 |
87% |
95%, 2009 |
70%, 2011 |
Mean Humidity |
85% |
|
71% |
90%, 2021 |
50%, 2012 |
Minimum Pressure |
1006 hPa |
18:12 |
1016 hPa |
1019 hPa, 2025 |
1004 hPa, 2015 |
Maximum Pressure |
1012 hPa |
00:03 |
1021 hPa |
1023 hPa, 2009 |
1011 hPa, 2021 |
Mean Pressure |
1009 hPa |
|
1018 hPa |
1020 hPa, 2025 |
1009 hPa, 2020 |
Mean Wind Speed |
6.3 mph (+2.0) |
|
4.9 mph (+0.6) |
6.8 mph, 2022 |
2.3 mph, 2018 |
Maximum Wind Speed |
18.7 mph |
13:42 |
13.3 mph |
18.7 mph, 2020 |
8.1 mph, 2021 |
Maximum Gust |
26.5 mph |
14:35 |
20.8 mph |
27.4 mph, 2016 |
10.7 mph, 2011 |
Mean Wind Direction |
SW |
|
|
|
|
Rainfall |
4.3 mm |
|
31.7 mm (85%) |
38.4 mm, 2021 |
|
Maximum Hourly Rain |
1.4 mm |
16:17 |
|
25.5 mm, 2021 |
|
Maximum 10-min Rain |
0.5 mm |
15:27 |
|
10.4 mm, 2021 |
|
Maximum Rain Rate |
18 mm/h |
16:17 |
|
102 mm/h, 2014 |
|
Minimum Dew Point |
13.4 °C |
22:16 |
9.9 °C |
15.1 °C, 2021 |
4.3 °C, 2011 |
Maximum Dew Point |
17.1 °C |
11:08 |
14.1 °C |
21.1 °C, 2019 |
11.0 °C, 2011 |
Mean Dew Point |
15.5 °C |
|
12.1 °C |
17.4 °C, 2019 |
7.5 °C, 2011 |
Measure | Value | Time |
Month cumul. | Record High | Record Low |
Night Minimum (21-09) |
* 17.4 °C * |
05:39 |
13.7 °C |
19.4 °C, 2019 |
10.4 °C, 2011 |
Day Maximum (09-21) |
21.4 °C |
13:21 |
22.0 °C |
36.8 °C, 2019 |
20.2 °C, 2023 |
Max 10m Temp Rise |
0.4 °C |
11:47 |
0.6 °C |
1.1 °C, 2012 |
0.3 °C, 2024 |
Max 1hr Temp Rise |
1.7 °C |
12:26 |
2.2 °C |
4.7 °C, 2012 |
1.3 °C, 2024 |
Max 1hr Hum Rise |
12% |
15:34 |
10% |
28%, 2014 |
4%, 2025 |
Max 10m Temp Fall |
0.5 °C |
21:09 |
0.6 °C |
2.6 °C, 2014 |
0.4 °C, 2010 |
Max 1hr Temp Fall |
1.8 °C |
15:39 |
2.1 °C |
5.6 °C, 2014 |
1.2 °C, 2010 |
Max 1hr Hum Fall |
9% |
12:08 |
10% |
20%, 2015 |
5%, 2021 |
Max 10m Wind Speed |
12.5 mph |
14:47 |
9.7 mph |
12.7 mph, 2016 |
3.5 mph, 2009 |
Minimum Feels-like |
18.2 °C |
22:23 |
14.8 °C |
23.1 °C, 2019 |
10.4 °C, 2011 |
Maximum Feels-like |
26.7 °C |
13:19 |
24.7 °C |
44.6 °C, 2019 |
21.8 °C, 2023 |
Mean Feels-like |
22.3 °C |
|
20.1 °C |
34.1 °C, 2019 |
16.1 °C, 2015 |
Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
Temperature Range |
6.4 °C (-2.2) |
8.5 °C (-0.3) |
17.4 °C (+8.8), 2019 |
4.4 °C (-4.2), 2024 |
Humidity Range |
18% |
33% |
52%, 2009 |
12%, 2024 |
Pressure Range |
6 hPa |
5 hPa |
13 hPa, 2015 |
2 hPa, 2013 |
Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
Sun Hours |
0.1 [1%] | 130 hrs (82%) [35%] |
13 [91%], 2012 |
0 [0%], 2021 |
Wet Hours |
5 [Mean rain rate: 0.9 mm/h] | 41 hrs (150%) [6.8%] |
7, 2021 |
0, 2009 |
Cloud Cover |
Overcast |
Events |
None |
Comments |
Showers |
Extra Comments |
|
Issues |
no pond temp due to covid |
Observer Absent? |
Yes - observations may be unreliable |
Pond Temperature @ Hampstead Heath |
5.0 °C |