1st day of fall 2024: What is the autumnal equinox and when is it?

Photographer captures foggy morning, autumnal activity

A photographer captured video of the moment Friday morning’s fog lifted, revealing a New England treeline transitioning into shades of red, orange and yellow.

Even though pumpkin spice-flavored everything made a premature return to menus and store shelves everywhere, the first day of fall is actually this Sunday.

Sept. 22, marks the first day of the autumnal equinox in the Northern Hemisphere, according to the Farmer’s Almanac. It begins approximately at 8:43 a.m. ET.

Meanwhile, meteorological fall begins on Sept. 1 and makes it easier to keep seasonal weather records, according to FOX Weather.

What is the autumnal equinox?

During the autumnal equinox, the Earth’s axis and its orbit line up so that both hemispheres get an equal amount of sunlight.

The word equinox comes from two Latin words meaning equal and night. That’s because on the equinox, day and night last almost the same amount of time — though one may get a few extra minutes, depending on where you are on the planet.
Difference between meteorological and astronomical seasons
Meteorological seasons are defined by the weather. They break down the year into three-month seasons based on annual temperature cycles. By that calendar, spring starts on March 1, summer on June 1, fall on Sept. 1 and winter on Dec. 1.

Astronomical seasons depend on how the Earth moves around the sun.

Equinoxes, when the sun lands equally on both hemispheres, mark the start of spring and autumn. Solstices, when the Earth sees its strongest tilt toward or away from the sun, kick off summer and winter.

Fall 2024 weather outlook

NOAA’s Climate Prediction Center says much of the U.S. will likely experience a warm and dry autumn.

The temperature outlook for the period of September to November shows that few places will see average temperatures, according to FOX Weather. The warmest weather is expected in the Northeast, South Florida, the Four Corners and northern Alaska.

The peak of the Atlantic hurricane season is Sept. 10, just days after the start of meteorological fall. That means there’s a decent shot that a tropical system could bring heavy rain to the East Coast.

The Northwest is also expected to see above-average precipitation, as is western Alaska.
Below-average precipitation is likely in much of the central U.S., the Intermountain West, the Southwest and southern Alaska.