Winter Solstice 2019
Winter officially begins with the winter solstice on December 21 2019 at 11:19 pm. For the northern hemisphere this is the fewest hours of sunlight for the year. The word solstice is Latin, “Sol” means Sun, “Sistere” means to stand still. During the winter solstice, the sun has reached it most southern point for the northern hemisphere. For the southern hemisphere, this is the summer solstice. The next day, the path of the sun will advance northward. Few days before and after the winter solstice, the sun’s path seems to stay the same or stand still. The sun is directly overhead at high-noon on winter solstice at the latitude called the Tropic of Capricorn. After the winter solstice occurs, the next day the earth will start slightly titling in the other direction. As the days lengthens, the cold weather (know as seasonal lag) starts really setting in. Most areas coldest temperatures are during January. The reason for the seasonal lag, because the amount of solar energy that will arrive at the ground is less than the amount leaving the earth surface. Oceans and other bodies of water keep temperatures from rising fast. Oceans and water take longer to heat up and cool down. So, this is the reason that the seasonal lag happens.
The winter solstice actually marks the shortest daylight of the year, not the latest sunset of the year. The picture below actually shows which dates the earliest sunsets actually occur in the US. I know this is a little confusing, but during the solstice, the sunset will be a few minutes later than the actual earlier sunset that occurred early in the month of November and December.
Here are a few more really cool facts about the different seasons through out the year. The solstice is the beginning of astronomical winter. Astronomical seasons are based on the position of the Earth to the Sun. Meteorological seasons are based on the annual temperatures. For winter, the meteorologic calendar season is from December 1st to March 1st. The astronomical calendar is December 21st to March 21st.
I am no fan of the winter months at all. The best part, for me, about the winter solstice is that I know the earth will start titling in the opposite direction and the days will start getting longer.