Summer Solstice London

 Friday, June 20, 2025

Tomorrow is the summer solstice (3:42am BST).
Today and tomorrow are the longest days.
But tonight is the shortest night.

Date	Sunrise	Day length	Sunset	Night length
Jun 15	04:42:13	16h37m54s	21:20:07	7h22m03s
Jun 16	04:42:10	16h38m24s	21:20:34	7h21m35s
Jun 17	04:42:09	16h38m50s	21:20:59	7h21m13s
Jun 18	04:42:12	16h39m08s	21:21:20	7h20m57s
Jun 19	04:42:17	16h39m21s	21:21:38	7h20m48s
Jun 20	04:42:26	16h39m28s	21:21:54	7h20m42s
Jun 21	04:42:38	16h39m28s	21:22:06	7h20m47s
Jun 22	04:42:53	16h39m22s	21:22:15	7h20m55s
Jun 23	04:43:10	16h39m11s	21:22:21	7h21m10s
Jun 24	04:43:31	16h38m53s	21:22:24	7h21m30s
Jun 25	04:43:54	16h38m30s	21:22:24	7h21m57s
Jun 26	04:44:21	16h38m00s	21:22:21	7h22m29s

data is for London, specifically the Houses of Parliament (51.5°N, 0.125W°)

Days are longer than 16h39m from June 18th to June 23rd.
Nights are shorter than 7h21m from June 18th to June 22nd.

We've already had the earliest sunrise (4:42am and 9 seconds) three days ago.
But the latest sunset (9.22pm and 24 seconds) isn't until next week.
Sunsets are still getting fractionally later for the next four days.
This is for previously-explained reasons.

All this balances out, marginally, to give a longest day of 16h39m28s.
This year June 20th and June 21st both have the same maximum day length.
This is because the solstice occurs overnight, inbetween.

It also means the night of the solstice is the shortest night.
Which is tonight.
But it's only 5 seconds shorter than tomorrow night, so nobody will notice.