Meteorological Fall Commences Today Amid Leaf-Color Forecasts

Washington, D.C., September 1, 2025 - Autumn officially arrives today for meteorologists across the Northern Hemisphere, marking the first day of fall’s 91-day span even though astronomical autumn doesn’t begin until the equinox on September 22.

Meteorological seasons divide the year into four equal three-month periods based on average temperatures:

This convention aids climatologists in tracking and comparing seasonal weather patterns without the shifting dates of astronomical events.

“Labor Day Fall” and Foliage Projections

Since Labor Day falls on September 1 this year, many Americans will celebrate the holiday weekend under crisp, fall-like conditions rather than summer heat. Local meteorologist Justin Weather reports that much of the country woke to cooler morning highs, with surface high pressure drawing northeasterly breezes that will keep temperatures below seasonal averages in several regions.

Additionally, two interactive mapping tools released today project the timing of peak fall colors in every U.S. state. These maps forecast that northern states such as Vermont and Wisconsin will see foliage changes by late September, while southern regions like Texas and Florida may not reach peak color until well into October.

Looking Ahead to the Autumnal Equinox

Astronomical autumn, defined by the moment the sun crosses the celestial equator, will occur on September 22 at 2:19 p.m. ET. At that instant, daylight and nighttime hours will be nearly equal worldwide, after which daylight will steadily shorten until the winter solstice on December 21.

As the leaves begin their annual transformation, meteorologists and nature-lovers alike will monitor both temperature trends and interactive foliage forecasts to celebrate the vivid hues of the season’s early days.