For those of us living in the Northern Hemisphere, Saturday will mark the official astronomical start of winter, also known as the Winter Solstice.

It occurs at the moment the sun is over the Tropic of Capricorn, 8:19 pm PT when the Northern Hemisphere will be tilted farthest away from the sun.

Just how much sunlight you actually get on Saturday will depend on where you are located but generally, most will get 8-10 hours of sunlight.

Source: https://www.ktvu.com/news/winter-solstice-the-shortest-day-of-the-year-is-upon-us