July 21, 2026 · Viana do Castelo, Portugal
Viana do Castelo has 14h 46m of daylight today. Sunrise is at 06:19 and sunset is at 21:05. All times are calculated astronomically for Viana do Castelo's exact coordinates.
Viana do Castelo lies at 42°N. At this latitude, day length varies moderately — from around 10 hours in midwinter to 14–15 hours in midsummer.
Day length changes fastest near the spring and autumn equinoxes and slowest near the longest day and shortest day of the year. See the year chart to visualise how daylight hours shift month by month for Viana do Castelo, or see daylight hours for every day of the year.
The longest day in Viana do Castelo is around 15h 12m (around June 21). The shortest is around 9h 9m (around December 21). Days are currently getting shorter — losing about 2 minutes per day.
| Month | Day length | Sunrise | Sunset |
|---|---|---|---|
| January | 9h 27m | 08:01 | 17:29 |
| February | 10h 34m | 07:33 | 18:07 |
| March | 11h 51m | 06:50 | 18:41 |
| April | 13h 17m | 06:58 | 20:15 |
| May | 14h 29m | 06:18 | 20:47 |
| June | 15h 11m | 06:01 | 21:12 |
| July | 14h 56m | 06:14 | 21:10 |
| August | 13h 55m | 06:43 | 20:39 |
| September | 12h 34m | 07:15 | 19:49 |
| October | 11h 11m | 07:47 | 18:57 |
| November | 9h 54m | 07:24 | 17:17 |
| December | 9h 11m | 07:55 | 17:06 |