The color of the sunlight in the evening or late afternoon is different than the light during the day. It has a very warm, orange look to it that saturates everything. The shadows are longer and more of a blue and reddish violet. The morning light is a little cooler, midday light is muted and flat, but evening light is warm and orange. If I'm painting outside in the late afternoon I will pre-mix an orange with alizarin crimson and cadmium yellow light and use it in all the sunlit areas along with the local color. For example, a green tree in evening light will have orange added to it. The shadow areas will be affected with ultramarine blue and alizarin crimson along with the local color.