Change how sunlight and shadows affect your scene during different times of the day and year. Open the Daylight tool in Daylight / Weather 
.
Sunlight slider
Drag the Sunlight slider 
left and right to adjust the sunlight and shadows in your scene at different times of the day. You can also adjust the time of day by manually entering it or by clicking specific times on the slider. To change time zones, click the current time zone to the right of the time box and choose from the drop-down list.
Note:
The Daylight tool uses UTC time and does not account for the daylight saving times in different countries and regions of the world.
Click Play 
to animate
the sunlight as it cycles through the day in your scene.
Calendar
Click the Calendar drop-down menu to change the sun's position at different times of the year.
Click Play to animate
the sunlight as it cycles through the
months in a year in your scene.
Lighting
Sometimes when viewing scenes, the amount of light based on the sun position darkens the scene, especially in polar areas. Uncheck the Sun position by date and time checkbox to add lighting that illuminates the scene, in which the light source is fixed relative to the camera and ensures the scene is always well lit.
Shadows
Check the Shadows checkbox to illustrate shadows in your
scene. You can change shadow effects by adjusting the Sunlight slider , time zone, and Calendar options.