See how the autumnal equinox will change daylight in your area using this tool
The autumnal equinox begins Tuesday night, officially marking the start of fall in the Northern Hemisphere. Autumn brings cooler temperatures, falling leaves and – shorter days, meaning less sunlight. But how much less?
From the autumnal equinox through the winter solstice, states across the U.S. can lose a total of 3 to 3.5 hours of daylight, according to data from NOAA.
But how much shorter will your days get? The Get the Facts Data Team calculated the average amount of daylight each zip code receives using data from NOAA’s solar calculations, to help determine how much shorter your days get.
Use the tool below to see how the average amount of daylight changes throughout the year in your zip code.
Why do days get shorter?
Earth’s axis is titled about 23.5 degrees. As Earth orbits the Sun, the amount of daylight changes throughout the year.
Shorter days occur as the Northern Hemisphere gradually tilt away from the Sun. In plain terms, less sunlight reaches the Earth’s surface, making the days shorter. The winter solstice marks the shortest day of the year, when Earth’s tilt is farthest from the Sun.
Even though fall and winter bring less daylight, some cities receive more total daylight over the course of a year. This year, downtown Boston will get nearly 4,460 hours of daylight, compared to downtown Orlando which will get about 4,440 hours.
Cities that are closer to the equator, meaning lower in latitude, tend to experience less seasonal changes in daylight. But cities farther from the equator have much longer summer days, which increases their total annual daylight.