If you were outside at 8:03 p.m. Thursday preparing a seasonal welcome, you undoubtedly greeted what happened with as much autumnal equinox enthusiasm as you could muster on an unseasonably warm Oklahoma evening in September.

That‚s right, today‚s the first full day of fall, it‚s no longer summer, despite what the thermometer might indicate.

It‚s that time of the year when some people buy all the pumpkin spice lattes they can drink, while others grip onto the last days of warm summer sunshine.

The passage from summer to fall means — eventually — sweater weather and cooler temperatures, and a growing number of dark hours as each day passes.

Autumn is a season of various emotions — sadness that summer is passed, and joy for the changing colors of leaves; dread of shorter days, and excitement for upcoming holidays; and grief for those no longer here, and anticipation of new memories still to be made.

No matter if you view it with dread or delight, the autumnal equinox occurred and we‚re in the home stretch for Halloween, Thanksgiving and Christmas.

Autumnal is the easy one, but what is an equinox, and why use it?

Equinox comes from a couple of Latin words, and means “equal night.” It‚s when the noon sun is directly overhead at the equator … well, for at least a moment anyway. When the sun is directly overhead at the equator, the expectation is that the whole earth experiences 12 hours of daylight and 12 hours of darkness.

But that‚s not what really happens. Equal nights didn‚t happen last night, and equal days probably won‚t happen today. The reality is that the actual occurrence of equal day and equal night happens in the next few days.

In Oklahoma, as well as with our neighbors in Arkansas, Texas and across the map, the summer that ended Thursday didn‚t just seem hotter than usual, data shows it really was as the climate crisis pushed temperatures into record territory.

Since June 1, almost 400 all-time heat records were registered from California to Maine, according to an analysis of National Oceanic and Atmospheric Administration data from the past 30 years. In Sequoyah County, summer temperatures flirted with the century mark on several occasions, the most recent occurring this week.

But cooler temperatures reminiscent of mid-September — when it was 80.6 degrees on Sept. 11 and 82.4 degrees on Sept. 12 — are forecast to return next week.

And it will get better. Highs a month from now are expected to be in the upper 70s, and by the first week of November, temperatures will top out in the upper 60s. Before autumn becomes winter in the waning days before Christmas, highs will be in the 50s, with 40s on tap for the new year.