Daylight hours in Saint Peter Port
Saint Peter Port gets 16h 15m of daylight on its longest day in June, and 8h 11m on its shortest in December — a difference of 8h 04m across the year.
How fast the days change
Around 17 March, Saint Peter Port gains or loses about 3.7 minutes of daylight every day.
Enough to notice over a fortnight, though the seasons arrive more gently here than further from the equator.
Sunrise and sunset by month
On the 15th of each month, in Europe/Guernsey local time, daylight saving included.
| Month | Sunrise | Sunset | Daylight | Solar noon |
|---|---|---|---|---|
| January | 08:00 | 16:38 | 8h 38m | 12:19 |
| February | 07:19 | 17:29 | 10h 10m | 12:24 |
| March | 06:23 | 18:14 | 11h 51m | 12:19 |
| April | 06:17 | 20:02 | 13h 44m | 13:10 |
| May | 05:26 | 20:47 | 15h 21m | 13:06 |
| June | 05:03 | 21:18 | 16h 15m | 13:10 |
| July | 05:20 | 21:11 | 15h 52m | 13:16 |
| August | 06:01 | 20:27 | 14h 26m | 13:14 |
| September | 06:46 | 19:24 | 12h 38m | 13:05 |
| October | 07:31 | 18:20 | 10h 49m | 12:55 |
| November | 07:21 | 16:28 | 9h 07m | 11:54 |
| December | 07:59 | 16:10 | 8h 11m | 12:05 |
Solstices and equinoxes
| Date | Sunrise | Sunset | Daylight | |
|---|---|---|---|---|
| March equinox | 20 Mar | 06:12 | 18:22 | 12h 10m |
| June solstice | 21 Jun | 05:03 | 21:20 | 16h 17m |
| September equinox | 22 Sep | 06:56 | 19:09 | 12h 12m |
| December solstice | 21 Dec | 08:03 | 16:12 | 8h 09m |
The equinoxes give almost exactly twelve hours of daylight everywhere on earth — "almost" because sunrise is defined by the sun's upper edge rather than its centre, and the atmosphere bends its light over the horizon before it has really arrived. Both lengthen the day by a few minutes.
Assumptions
- Sea-level horizon. Hills, mountains and buildings all delay sunrise and bring sunset forward, sometimes by a lot in a valley.
- Standard refraction. Sunrise is taken at −0.833°, allowing for the sun's disc and average atmospheric bending. Unusual air conditions shift it by a minute or two.
- Local clock time, with daylight saving applied from the IANA timezone database.