Daylight hours in Saint-Denis
Saint-Denis gets 13h 23m of daylight on its longest day in December, and 10h 52m on its shortest in June — a difference of 2h 31m across the year.
How fast the days change
Around 17 March, Saint-Denis gains or loses about 1.2 minutes of daylight every day.
Barely perceptible — near the equator the length of the day hardly changes at all, and the seasons announce themselves through rain and heat instead.
Sunrise and sunset by month
On the 15th of each month, in Indian/Reunion local time, daylight saving included.
| Month | Sunrise | Sunset | Daylight | Solar noon |
|---|---|---|---|---|
| January | 05:49 | 19:05 | 13h 15m | 12:27 |
| February | 06:09 | 18:55 | 12h 47m | 12:32 |
| March | 06:20 | 18:33 | 12h 14m | 12:27 |
| April | 06:29 | 18:06 | 11h 37m | 12:18 |
| May | 06:40 | 17:48 | 11h 08m | 12:14 |
| June | 06:52 | 17:44 | 10h 52m | 12:18 |
| July | 06:54 | 17:53 | 10h 59m | 12:24 |
| August | 06:40 | 18:04 | 11h 24m | 12:22 |
| September | 06:14 | 18:12 | 11h 58m | 12:13 |
| October | 05:47 | 18:20 | 12h 34m | 12:03 |
| November | 05:29 | 18:35 | 13h 06m | 12:02 |
| December | 05:31 | 18:54 | 13h 23m | 12:13 |
Solstices and equinoxes
| Date | Sunrise | Sunset | Daylight | |
|---|---|---|---|---|
| March equinox | 20 Mar | 06:21 | 18:29 | 12h 07m |
| June solstice | 21 Jun | 06:54 | 17:45 | 10h 52m |
| September equinox | 22 Sep | 06:07 | 18:14 | 12h 06m |
| December solstice | 21 Dec | 05:34 | 18:58 | 13h 24m |
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.
Other cities in Reunion
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.