Seasonal shadows
How sun shadows change throughout the year
The same wall, tree or building casts a short shadow in summer and a long one in winter because the sun travels at a different height.
By SunCast team Last updated: October 14, 2026
Short answer
Sun shadows change throughout the year because the sun path changes with the seasons. When the sun is higher in the sky, shadows are shorter. When the sun is lower in the sky, shadows are longer and can reach farther across rooms, gardens, streets, roofs, and neighbouring properties.
Shadow pattern by season
| Term | Meaning |
|---|---|
| High sun | Shorter shadows, common around summer midday. |
| Low sun | Longer shadows, common in winter and near sunrise or sunset. |
| Morning and evening | Long shadows because the sun is low. |
| Midday | Shortest daily shadows because the sun is usually highest. |
Why shadow length changes
Shadow length depends on sun elevation: shadow length equals object height divided by the tangent of the elevation. A low sun stretches shadows and a high sun shortens them.
Because the sun path changes through the year, a shadow check on one date can miss the pattern in another season.
A 10 m building in Amsterdam through the year
Take a 10 m, roughly three-storey building in Amsterdam. On 21 June the sun reaches 61.1° at 13:43 CEST and the noon shadow is 5.5 m long. At the March and September equinoxes the noon sun is about 37.5° high and the shadow is about 13 m. On 21 December the sun only reaches 14.2° at 12:39 CET, and the noon shadow is 39.5 m. At 10:00 that morning, with the sun at 6.7°, it is about 85 m (calculated with SunCast’s sun calculator).
So a garden 20 m north of that building is in sun at midday from spring to autumn and in its shadow at noon in midwinter.
Why direction changes too
Shadows point directly away from the sun. As sunrise and sunset directions shift through the year, shadow directions shift with them.
At 10:00 on 21 June the Amsterdam building’s shadow points almost due west (282°); at 10:00 on 21 December it points north-west (324°). At 16:00 in June it points north-east (55°). A garden, window or solar roof can therefore behave differently in March, June, September and December.
Where seasonal shadows matter
Homes
A neighbouring building may miss a window in summer but shade it in winter when the sun is lower.
Gardens
A fence shadow can cross a bed in spring or autumn even if the bed gets strong summer sun.
Solar planning
A roof can look clear on one date and still need a winter shade check before design work begins.
Construction
A planned structure can have a very different shadow impact in winter than in summer.
Limits
Shadow calculations depend on solar position and the geometry available. Trees, small objects, local terrain and detailed building shapes may still need an in-person check.
Check it in SunCast
Need to see seasonal shadows for a real place? SunCast’s 3D map casts shadows from mapped buildings and terrain for any date and time.
Frequently asked questions
When are shadows longest?
Each day, shadows are longest near sunrise and sunset. Over the year, they are longest in winter because the sun stays lower in the sky.
Why are summer shadows shorter?
In summer the sun travels higher, especially around midday. In Amsterdam a 10 m building casts a 5.5 m noon shadow in June and a 39.5 m one in December.
Should I check shadows in winter or summer?
Check both if the decision matters. Winter shows the longest shadows, while summer shows heat, glare and high-sun conditions.
