Winter Solstice does not also mean Latest Sunrise

Last blog we focused on our earliest sunsets and how it approached that mark before the winter solstice. The 1st factor affecting sunrises and sunsets was explored through the solar day and solar noon. This blog will focus on the latest sunrise of the year and another factor that plays a roll on the timing of when the sunshine is received throughout the year.

The next factor that keeps the sunrises and sunsets from their extreme on the solstices is the earth’s proximity to the sun. The aphelion (earth’s farthest point from the sun) takes place in early July while the perihelion (earth’s closest point from the sun) takes place in early January. These two points play a role on the time difference of when the extreme sunrise or sunset take place compared to its solstices.

The speed of movement in the orbit is fastest in the perihelion and slowest in the aphelion.  The speed of the orbit’s movement is shown on the earliest sunset and latest sunrise to be happening a bit farther apart from the winter solstice by almost 2 weeks. You would believe the same would hold for the earliest sunrise and latest sunset of the year but it actually happens about a week from the summer solstice.

In Salisbury, it was previously mentioned that our earliest sunsets took place a few weeks ago but our latest sunrise will take place in a few days from now. During the winter solstice on December 21st, the sunrise is at 7:15 AM and it will be until this upcoming Sunday on December 30th, when our sunrise is at its latest at 7:19 AM.  This late sunrises will continue for 2 weeks as it enters January before receiving an extra minute of morning light on January 13th at 7:18 AM.  A month after the winter solstice on January 21st, we are back to where it stood on December 21st with a sunrise at 7:15 AM. You have to wait a little longer for the first sunrise before 7 AM which will take place on February 9th. The last sunset before 7 AM in 2018 occurred on November 30th.

If you are an early bird, you are in luck once the New Year begins, the mornings gradually become longer, which will benefit you as the coldest days are upon us. The earlier sunrise will allow for our lows to arrive earlier in the morning thus starting our daily warming early as well.  We will revisit another factor to the sunrise and sunsets at a later time and focus on how these times alter somewhat during the summer solstice.

For information on the earliest sunset, check out that blog here, https://www.wmdt.com/2018/12/winter-solstice-does-not-mean-earliest-sunset/.

Categories: Weather Blog