Daylight hours in Lahti
Lahti gets 19h 12m of daylight on its longest day in June, and 5h 36m on its shortest in December — a difference of 13h 36m across the year.
How fast the days change
Around 12 March, Lahti gains or loses about 5.7 minutes of daylight every day.
That is quick enough to notice week to week, which is why spring seems to arrive all at once this far from the equator.
Sunrise and sunset by month
On the 15th of each month, in Europe/Helsinki local time, daylight saving included.
| Month | Sunrise | Sunset | Daylight | Solar noon |
|---|---|---|---|---|
| January | 09:12 | 15:40 | 6h 28m | 12:26 |
| February | 07:58 | 17:04 | 9h 05m | 12:31 |
| March | 06:34 | 18:18 | 11h 44m | 12:26 |
| April | 05:57 | 20:37 | 14h 40m | 13:17 |
| May | 04:31 | 21:55 | 17h 24m | 13:13 |
| June | 03:41 | 22:54 | 19h 12m | 13:17 |
| July | 04:11 | 22:34 | 18h 23m | 13:23 |
| August | 05:27 | 21:16 | 15h 50m | 13:21 |
| September | 06:44 | 19:40 | 12h 57m | 13:12 |
| October | 07:59 | 18:07 | 10h 08m | 13:03 |
| November | 08:21 | 15:42 | 7h 20m | 12:01 |
| December | 09:24 | 15:00 | 5h 36m | 12:12 |
Solstices and equinoxes
| Date | Sunrise | Sunset | Daylight | |
|---|---|---|---|---|
| March equinox | 20 Mar | 06:18 | 18:31 | 12h 13m |
| June solstice | 21 Jun | 03:41 | 22:57 | 19h 16m |
| September equinox | 22 Sep | 07:01 | 19:18 | 12h 17m |
| December solstice | 21 Dec | 09:29 | 15:01 | 5h 32m |
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 Finland
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.