London averages about 1,675 hours of sunshine a year and just 55 in December, under two hours a day. On the shortest day the sun is up for 7 hours and 50 minutes, sets before 4 pm and climbs only 15 degrees above the horizon at noon. Here is the London year in numbers, month by month, from Met Office data for Heathrow.
How grey is London in winter?
From November to January London gets between 55 and 71 hours of sunshine a month, and it rains on about 11 days in each of those months. The Met Office counts a rain day as 1 mm or more, so light drizzle days are not even in that total.
| London at a glance | Figure |
|---|---|
| Latitude (Heathrow) | 51.5°N |
| Sunshine hours a year | 1,675 |
| December sunshine hours | 55 |
| Days with 1 mm of rain or more | 112 |
| Rainfall a year | 615 mm |
| Shortest day (21 Dec 2026) | 7 h 50 min, sunrise 8:03 am, sunset 3:53 pm |
| Sun height at noon on the shortest day | 15° |
What does a London year look like month by month?
| Month | Sunshine hours | Days with 1 mm of rain or more | Rainfall (mm) |
|---|---|---|---|
| January | 61 | 11.5 | 59 |
| February | 79 | 9.5 | 45 |
| March | 124 | 8.5 | 39 |
| April | 177 | 8.8 | 42 |
| May | 207 | 8.0 | 46 |
| June | 208 | 8.3 | 47 |
| July | 218 | 7.9 | 46 |
| August | 202 | 8.4 | 53 |
| September | 157 | 7.9 | 50 |
| October | 115 | 10.8 | 65 |
| November | 71 | 11.2 | 67 |
| December | 55 | 10.8 | 57 |
How does London compare with Seattle?
London is further north than Seattle (51.5°N against 47.4°N), so its winter days are shorter. On 21 December the sun sets at 3:53 pm in London and 4:20 pm in Seattle. December sunshine is almost the same, about 55 hours in London and 53 in Seattle. Over a full year Seattle gets more sun, about 2,170 hours to London's 1,675, thanks to its dry summers.
Do you need vitamin D in a London winter?
The NHS advises everyone in the UK to consider taking 10 micrograms of vitamin D a day from October to March, because the sun is not strong enough for the skin to make it (NHS). Research at 52°N, almost exactly London's latitude, found no vitamin D was made from sunlight from October through March (Webb, Kline and Holick, 1988).
FAQ
What is the darkest month in London?
December, with about 55 hours of sunshine and the shortest days of the year.
How many days does it rain in London?
About 112 days a year have 1 mm of rain or more, according to Met Office averages for Heathrow.
What time does it get dark in London in winter?
Around the shortest day the sun sets just before 4 pm.
Ray™'s take: Dark by four is a lot. Bring your own weather. See how London compares in The Grey Index.
Sources and method
Sunshine, rain days and rainfall: Met Office averages for Heathrow, 1991 to 2020. The Met Office counts rain days at 1 mm or more, while NOAA counts US rain days at 0.01 in (about 0.25 mm), so rain days are not directly comparable between London and US cities. Sunrise, sunset and sun height for 21 December 2026: timeanddate.com. This page is for education and is not medical advice.