(NEWS CENTER) -- Our ninth month begins on Monday. Here are some interesting dates to add to your calendar this month, weather wise:
- Sunrise/sunset for 9/1 is 6:04am/7:16pm. By the 30th, the times are 6:37am/6:24pm. The length of daylight decreases 1 hour, 25 minutes this month from start to finish.
- Average temperatures in Portland on 9/1 are 75°/55° (high/low). On the 30th, average temperatures cool to 65°/44°. The average first frost in northern and northwestern Maine occur in the beginning and middle parts of the month, respectively, according to almanac.com.
- September 1 marks the beginning of "meteorological autumn." Why do meteorologists and climatologist not use the same date as the equinox (9/22)? Because, as you may have noticed, the equinoxes and solstices do not fall on the same day every year. This is because our calendar is based on a 365-day year, when in actuality, Earth completes a complete orbit around the sun every 365.25 days. That quarter of a day pushes the equinoxes back about six hours every year. Using the first of the month creates a definitive boundary between seasons; winter consists of December, January, and February, spring is March, April, and May, summer is June, July, and August, and autumn (fall) is September, October, November.
- The third and final full "super moon" occurs on the night of September 8-9. Three consecutive visible super moons occur in 2014 during the months of July, August, and September, the largest of which occurred in August. Since this month's full moon is the closest to the actual autumnal equinox, it is considered the "Harvest Moon."
- The autumnal equinox occurs on September 22 at 10:29 EDT. This is the moment when the sun is shining directly over the equator, bringing equal length of daylight to all points on Earth. Here's something you may not know: because the sun is rising and setting almost directly due east and west, this is the time of year when the speed of the sunrise and sunset is fastest. In other words, the time it takes for the sun's disk to pierce the horizon and either fully clear or fully disappear beneath the horizon is shorter than during the solstices. This is because during the period around solstice, the sun is rising and setting at an angle, versus rising and setting "directly up and down."
Of course, September is the time of year when the leaves begin to change from north to south. We always encourage you to share your photos of Maine's beautiful fall foliage on our Facebook page.