Sun or shade? How to plan a mountain trip around the sun

Which side of a valley is sunny?

In the northern hemisphere, the north side of an east–west valley, facing south, gets the most sun; the south side, facing north, can stay in shade all winter. In a north–south valley, east-facing slopes generally receive morning sun and west-facing slopes afternoon sun; nearby ridges change the timing.

That north/south rule describes the northern hemisphere; in the southern hemisphere, north-facing slopes generally get more sun. Near the tropics, the season also changes which side the midday sun occupies. Use the selected pin and date instead of applying one compass rule everywhere. In Yosemite Valley in 2027, El Capitan Meadow, under the high walls of the valley's south side, has no direct sun at all around the winter solstice, while the summit of El Capitan above it has sun all day. See El Capitan sun and shade.

When are mountain lakes in the sun?

Later than you think, because lakes lie at the bottom of their basin. Lago di Braies gets direct sun from 09:18 on 21 June; Lago di Sorapis from 10:35 in late September and not at all on 21 December.

For photographs of sunlit water, check when direct light reaches the actual pin. For reflections, compare a shaded lake with a lit peak and check wind separately; sunlight alone predicts neither calm water nor water temperature. Sun times for nine Dolomites spots has the details.

Where can travelers see the sunrise in the mountains?

From high ground with an open view east, such as a summit, a pass or a hut. On Seceda the sun appears at 05:15 on 21 June, even before the flat-horizon sunrise of 05:20; in a valley village the first sun may come one or two hours later.

Mountain huts and passes reachable by road (Passo Giau in the Dolomites, for example) are the easy option; summit sunrises mean starting in the dark, since lifts usually open later. In a valley you can still enjoy the sunrise colours on the peaks above you, which is often the better view.

How short is a winter day in a mountain village?

Often half of the official day or less. On 21 December Ortisei in Val Gardena has direct sun 09:50–11:50 (2 h 1 min), Cortina 08:56–15:18 (6 h 22 min), and Alpe di Siusi above them 6 h 32 min.

For a sunny winter holiday choose a wide basin or a high plateau over a narrow valley, and plan outdoor lunches for the hours the village is in the sun. In Bovec, Slovenia, the first winter sun comes at 08:52, over an hour after the official sunrise (Bovec sun times).

How do you find shade on a hot day?

Use the terrain: walls and gorges can block direct sunlight for hours; shade does not predict temperature or exposure on the whole route. In summer the lower wall of El Capitan is in shade until 11:22, and gorges are shaded early and late in the day.

Check selected stopping points along a walk individually, then make your route and timing decisions yourself. The app does not yet analyse a complete walking route. The Great Soča Gorge gets sun 07:19–19:11 in August but only 10:14–13:03 in December (visitor guide). El Capitan Meadow, below the wall, has sun 06:13–18:40 in June.

How do you check the sun for your own trip?

Look up the place and the day in an app that counts the terrain, not a sunrise table. Sunreach gives the time the sun is on any spot you pick, for any day of your trip, and states the terrain source and estimated accuracy.

Sunrise tables and weather apps assume a flat horizon; why that is wrong in the mountains.

Before you go, download the region for offline use if you will lose signal, and look through the app’s photo spots for viewpoints near you. In towns, the 3D city view shows which terraces and streets are in sun (how it works).