Sun and shade map: which slopes the sun is on, hour by hour
Pick a day and an hour. The map lights the ground from where the sun stands then, so you can see which slopes are bright and which are in shade before you walk there in the dark.
What it shows
- The ground lit for a day and hour you pick. Bright slopes face the sun; dark ones are turned away from it.
- Sunrise, sunset and legal light for the spot, on the Colorado clock.
- Which way each slope faces, as its own layer, when you want the direction and not the hour.
Switch on "Sun and shade" under Terrain, then move the day and the hour.
What it is good for
- Choosing where to sit and look. Looking into the low sun across a basin is hard work. A spot with the sun behind you at first light is easier on the eyes and harder for an animal to pick out.
- Knowing when a slope warms. Air moves downhill while the ground is cold and starts uphill once the sun has been on a slope for a while. When that change comes depends on when the sun reaches the slope.
- Knowing when you will lose the light on the walk out. A north-facing drainage goes dark well before sunset.
For the legal minutes on any date and unit, use legal shooting hours by unit and date. For the hour-by-hour run of an opening day, read the opening morning timeline.
What it is not
The lighting is worked out from the height and direction of the sun and the shape of the bare ground. It shows which way slopes are turned to the sun, not the long shadow a far ridge throws, and it knows nothing about cloud, trees or snow.
The map shows the ground. A plan tells you where to go.
The map is free. A FilledTag hunt plan is the paid part: for your tag and where you drive from, one exact plan with a legal place to park, a camp, morning and evening spots and the walk between them, checked against land records.