Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
Minimum Temperature |
3.4 °C (+0.6) |
01:07 |
4.5 °C (+1.6) |
11.3 °C (+8.6), 2024 |
-1.5 °C (-4.2), 2009 |
Maximum Temperature |
11.7 °C (+3.6) |
19:15 |
9.0 °C (+1.0) |
13.3 °C (+5.2), 2024 |
4.3 °C (-3.8), 2010 |
Mean Temperature |
6.9 °C (+2.1) |
|
6.8 °C (+1.3) |
12.3 °C, 2024 |
2.2 °C, 2010 |
Minimum Humidity |
63% |
23:55 |
60% |
91%, 2024 |
48%, 2009 |
Maximum Humidity |
98% |
16:16 |
91% |
98%, 2013 |
78%, 2017 |
Mean Humidity |
81% |
|
77% |
92%, 2024 |
68%, 2021 |
Minimum Pressure |
975 hPa |
22:55 |
984 hPa |
1030 hPa, 2019 |
975 hPa, 2014 |
Maximum Pressure |
1000 hPa |
01:30 |
998 hPa |
1034 hPa, 2019 |
1000 hPa, 2014 |
Mean Pressure |
989 hPa |
|
991 hPa |
1032 hPa, 2019 |
989 hPa, 2014 |
Mean Wind Speed |
10.6 mph (+5.5) |
|
8.6 mph (+3.5) |
10.6 mph, 2014 |
1.0 mph, 2023 |
Maximum Wind Speed |
35.5 mph |
22:57 |
21.8 mph |
35.5 mph, 2014 |
6.0 mph, 2023 |
Maximum Gust |
49.7 mph |
22:56 |
33.2 mph |
49.7 mph, 2014 |
9.2 mph, 2023 |
Mean Wind Direction |
SSW |
|
|
|
|
Rainfall |
8.5 mm |
|
55.5 mm (247%) |
8.5 mm, 2014 |
|
Maximum Hourly Rain |
4.6 mm |
14:45 |
|
4.6 mm, 2014 |
|
Maximum 10-min Rain |
1.5 mm |
14:12 |
|
1.5 mm, 2014 |
|
Maximum Rain Rate |
18 mm/h |
14:07 |
|
18 mm/h, 2014 |
|
Minimum Dew Point |
-1.0 °C |
00:01 |
-0.2 °C |
10.0 °C, 2024 |
-5.9 °C, 2016 |
Maximum Dew Point |
10.5 °C |
16:57 |
6.5 °C |
11.9 °C, 2024 |
-1.1 °C, 2025 |
Mean Dew Point |
3.9 °C |
|
2.8 °C |
11.1 °C, 2024 |
-2.6 °C, 2021 |
Measure | Value | Time |
Month cumul. | Record High | Record Low |
Night Minimum (21-09) |
3.4 °C |
01:07 |
4.7 °C |
11.3 °C, 2024 |
-1.5 °C, 2009 |
Day Maximum (09-21) |
11.7 °C |
19:15 |
8.8 °C |
13.3 °C, 2024 |
4.3 °C, 2010 |
Max 10m Temp Rise |
0.6 °C |
15:52 |
0.4 °C |
0.9 °C, 2019 |
0.2 °C, 2010 |
Max 1hr Temp Rise |
2.6 °C |
16:21 |
1.3 °C |
3.2 °C, 2023 |
0.5 °C, 2024 |
Max 1hr Hum Rise |
11% |
21:10 |
8% |
14%, 2021 |
2%, 2024 |
Max 10m Temp Fall |
0.4 °C |
20:29 |
0.6 °C |
0.9 °C, 2022 |
0.1 °C, 2024 |
Max 1hr Temp Fall |
1.3 °C |
21:12 |
1.6 °C |
3.0 °C, 2023 |
0.4 °C, 2017 |
Max 1hr Hum Fall |
19% |
19:15 |
12% |
19%, 2014 |
2%, 2024 |
Max 10m Wind Speed |
26.6 mph |
23:04 |
16.1 mph |
26.6 mph, 2014 |
5.0 mph, 2023 |
Minimum Feels-like |
-1.0 °C |
00:49 |
-0.1 °C |
12.6 °C, 2024 |
-5.3 °C, 2021 |
Maximum Feels-like |
13.0 °C |
17:17 |
7.9 °C |
15.5 °C, 2024 |
2.3 °C, 2021 |
Mean Feels-like |
4.6 °C |
|
3.7 °C |
14.1 °C, 2024 |
-1.8 °C, 2021 |
Air-frost Hrs |
0 hrs |
|
0 hrs |
6 hrs, 2009 |
0 hrs, 2010 |
Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
Temperature Range |
8.3 °C (+3.0) |
4.5 °C (-0.5) |
12.7 °C (+7.4), 2019 |
2.0 °C (-3.3), 2024 |
Humidity Range |
35% |
31% |
48%, 2009 |
3%, 2024 |
Pressure Range |
25 hPa |
14 hPa |
25 hPa, 2014 |
3 hPa, 2025 |
Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
Sun Hours |
0 [0%] | 36 hrs (96%) [30%] |
8.9 [100%], 2019 |
0 [0%], 2014 |
Wet Hours |
7 [Mean rain rate: 1.2 mm/h] | 50 hrs (192%) [15%] |
8, 2018 |
, 2009 |
Cloud Cover |
Overcast |
Events |
None |
Comments |
11-15 Rain, -22 occasional Showers |
Extra Comments |
|
Issues |
None known |
Observer Absent? |
No |
Pond Temperature @ Hampstead Heath |
0.0 °C |