The September Equinox

posted in: Michigan Weather Forecast, Slim | 10

This year the September equinox will arrive on Monday September 23, 2019 at 3:50 AM. For us in the Northern Hemisphere, it marks the calendar start of autumn (I use September 1st as the start of the fall season). At the equinox, days and nights just about equal in length. For us in the Northern Hemisphere, the sun is rising later now, and nightfall comes sooner. Meanwhile, south of the equator, spring is about to begin.
Over the years men have observed the changing of the days length and sun’s angle. The earliest of Our ancestors spent more time outside than we do. They used the sky as both a clock and a calendar. They could easily see that the sun’s path across the sky, the length of daylight, and the location of the sunrise and sunset all shift in a regular way throughout the year. Today, we know each equinox and solstice is an astronomical event, caused by Earth’s tilt on its axis and ceaseless orbit around the sun.
Because Earth doesn’t orbit upright, but is instead tilted on its axis by 23.5 degrees, Earth’s Northern and Southern Hemispheres trade places throughout the year in receiving the sun’s light and warmth most directly. We have an equinox twice a year – spring and fall – when the tilt of the Earth’s axis and Earth’s orbit around the sun combine in such a way that the axis is inclined neither away from nor toward the sun.
Earth’s two hemispheres are receiving the sun’s rays about equally around equinox-time. The sun is overhead at noon as seen from the equator. Night and day are approximately equal in length.
At Grand Rapids the sun rise on September 23rd this year is at 7:30 AM and the sun set is at 7:38 PM

For anyone who uses analog years for a winter’s guess well there is some bad news for any cold and snowy winter lovers. I just seen one of the better analog years for the upcoming winter is 2005/06. Yes that winter had tons of snow at Grand Rapids 69.2” but most of that snow fell in November (17.3”) and December (28.9”) note Christmas was still green. Then came January with just 9.6” of snow and a departure of +8.8° The coldest temperature that month was just 17° February was near average -0.4° but just 10.1” of snow fell. Also on Thursday the  CPC issued their long range guess and that guess is pointing toward a warm fall season thru December and then equal chances of above, average or below average for the winter season. And do not forget the “Old Farmers Almanac” guess for a warm winter in our area. Of course Joe Bastardi will tell us as he does every year how cold and snowy the winter will be. But just remember we will have to wait and see how this all plays out.

Slim


 


 

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Sandy (Hudsonville)
Sandy (Hudsonville)

GREAT POST SLIM! It has been a cloudy, drizzly day. It sure is humid so the a/c is running. I think I would rather that than the furnace. Not ready for that.

Jeff(Portland)
Jeff(Portland)

86 dew point 73 .. What happen to no 80s predicted by some last week. 😉 More above normal temps on the way.. Average high around 70 now . Which means anything higher is above normal .. Facts .. 😉

MichaelV

85* with a 72dp – rain is moving into the area – will put up the radar.

Mr. Negative
Mr. Negative

Hmmmm…looks like “time will tell” wether we receive any much needed rain at all.

Barry in Zeeland
Barry in Zeeland

Pretty odd looking at the beach web cams with so many boats and people out being this late in September. Just a ton of kite boards out at Grand Haven beach. How do they not smash into each other and get their lines all tangled up??

Mark (East Lansing)
Mark (East Lansing)

We’re hosting a baby shower in our backyard today. Forecasted to be 85° and muggy. Summer is going out with a bang.

Mr. Negative
Mr. Negative

Enjoy the shower. Never hurts to make a few passes over the yard with Mosquito/Insect spray :/

MichaelV

On a side note – Bill Steffen is in Madison Wisconsin his alma mater – Michigan plays the Badgers today. I give the Badgers the edge seeing they are at home. In the past Bill and I have bet on the game with a pound of coffee on the line – I lost when the Badgers played on their home field… you can see his post (link in the sidebar)…

Barry in Zeeland
Barry in Zeeland

Good read Slim. Always love astronomical events, proves the flat earthers are out of their minds! Crazy warm this morning went I came to work. 69 degrees! Wow, feels like mid July out. Keep the AC cranked right into October!