Historical Ranked Periods - Night Minimum (21-09) / °C · 5-day mean
Top 5-day mean
#
Value
Date
1
20.5
24–28 Jun 2026
2
19.5
6–10 Jul 2026
3
19.5
8–12 Aug 2020
4
19.0
28 Jun – 2 Jul 2025
5
18.4
23–27 Jul 2018
6
18.2
22–26 Jul 2019
7
18.1
31 Jul – 4 Aug 2022
8
18.1
18–22 Jun 2017
9
18.0
8–12 Sep 2023
10
18.0
19–23 Jul 2022
11
18.0
14–18 Aug 2012
12
17.9
6–10 Jul 2017
13
17.9
16–20 Jul 2016
14
17.8
12–16 Aug 2022
15
17.7
17–21 Jul 2014
16
17.7
19–23 Aug 2018
17
17.6
6–10 Sep 2016
18
17.6
30 Jul – 3 Aug 2024
19
17.5
17–21 Jul 2025
20
17.5
13–17 Aug 2020
21
17.2
19–23 Jun 2026
22
17.2
9–13 Jul 2022
23
17.2
8–12 Jul 2010
24
17.2
24–28 Aug 2016
25
17.2
21–25 Jul 2013
Bottom 5-day mean
#
Value
Date
1
-4.2
17–21 Dec 2010
2
-4.0
8–12 Feb 2012
3
-3.5
3–7 Jan 2009
4
-3.5
26 Feb – 2 Mar 2018
5
-3.4
13–17 Dec 2022
6
-3.4
4–8 Jan 2010
7
-3.1
31 Jan – 4 Feb 2012
8
-2.8
19–23 Dec 2009
9
-2.7
15–19 Jan 2024
10
-2.6
16–20 Jan 2013
11
-2.5
3–7 Dec 2010
12
-2.5
8–12 Jan 2025
13
-2.4
9–13 Feb 2021
14
-2.3
8–12 Dec 2022
15
-2.2
25–29 Nov 2010
16
-2.2
19–23 Jan 2023
17
-2.1
2–6 Jan 2026
18
-2.0
18–22 Jan 2017
19
-1.9
23–27 Dec 2010
20
-1.7
1–5 Feb 2009
21
-1.5
29 Nov – 3 Dec 2023
22
-1.4
30 Jan – 3 Feb 2019
23
-1.3
21–25 Jan 2013
24
-1.2
19–23 Jan 2015
25
-1.1
27–31 Mar 2013
Night Minimum (21-09) 5-day extremes: highest and lowest period means.
There are 6419 valid 5-day periods from 2009 to present in London, NW3 (complete windows only, hiding overlapping windows). Data for Night Minimum (21-09) begins in 1881.
Lowest air temperature overnight, from 21:00 to 09:00 local time.