When Does Fall Start? — the First Day of Autumn

Every year, as the summer heat begins to fade, people around the world start asking: When does autumn actually begin?
It might seem like a simple question, but the answer depends on how you define it. For some, fall arrives with the first yellow leaves or the start of the school year. For others, it begins the moment the Sun crosses the celestial equator — the autumn equinox.

Autumn is not just a bridge between summer and winter; it’s a season of change, reflection, and preparation. It influences agricultural cycles, cultural traditions, daily routines, and even people’s moods. In the Northern Hemisphere, fall is associated with cooler weather, harvests, and family celebrations; in the Southern Hemisphere, it marks the easing of summer heat and the gradual approach of winter.

The beginning of fall can be defined in two main ways:

• Astronomically, based on Earth’s position in its orbit around the Sun, and

• Meteorologically, based on fixed calendar months and observed weather patterns.

In the United States, Canada, the United Kingdom, Australia, and New Zealand, both systems coexist, reflecting differences in climate, culture, and even language — since some countries say fall while others prefer autumn.

Comparative Table: The Start and End of Autumn by Country

The contrast between the seasons in the Northern and Southern Hemispheres is caused by the tilt of Earth’s rotational axis — about 23.5 degrees relative to the plane of its orbit around the Sun.
When the Northern Hemisphere tilts toward the Sun, it experiences summer while the Southern Hemisphere experiences winter, and vice versa.

This is why the autumn equinox in the Northern Hemisphere (in September) corresponds to the spring equinox in the Southern Hemisphere (in March).
This consistent axial tilt creates a reliable rhythm of the seasons — a global balance that feels opposite depending on which side of the planet you live on.

Two Ways to Define the Start of Fall

A. Astronomical Autumn

The astronomical definition of fall is based on Earth’s position relative to the Sun.
The season begins at the autumnal equinox — the moment when Earth’s axis is tilted so that the Sun crosses the celestial equator and day and night are roughly equal in length.

In the Northern Hemisphere, this occurs around September 22–23, though the exact date can shift slightly each year due to the calendar cycle.
That day marks the start of astronomical autumn, which continues until the winter solstice — around December 21–22, when the day is shortest and the night is longest.

For skywatchers, the equinox is one of the most harmonious times of the year. Light is distributed almost evenly across the planet, and the Sun rises precisely in the east and sets precisely in the west.
This moment holds not only scientific significance but also deep symbolism — a balance between light and darkness, warmth and coolness, activity and rest.

In the Southern Hemisphere, the autumn equinox occurs around March 20–21. At this moment, for people in Australia, New Zealand, and nearby regions, fall begins and lasts until the June solstice.
While the Northern Hemisphere prepares for spring, the Southern Hemisphere enters a quieter, cooler season — a time of harvest and reflection.

Across many cultures in both hemispheres, the equinox has long been celebrated with festivals. It has symbolized transition, gratitude for the harvest, and preparation for shorter days — a natural reminder of life’s cycles and the harmony between opposites.

B. Meteorological Autumn

Meteorologists define autumn differently — for practical reasons.
To simplify weather observation and climate recordkeeping, they divide the year into equal, three-month meteorological seasons:

• In the Northern Hemisphere, fall runs from September 1 to November 30.

• In the Southern Hemisphere, it runs from March 1 to May 31.

This method provides consistency for comparing weather trends year after year. Meteorological seasons are based on average temperatures and long-term climate patterns, so they often better reflect the real changes people experience.

For instance, across much of North America, early September already brings cooler nights and the first hints of color in the trees.
By the time the equinox arrives, fall is already in full swing — at least from the perspective of weather, culture, and daily life.

When Autumn Begins in the US, the UK, Canada, Australia, and New Zealand

A. The United States and Canada

In both the United States and Canada, autumn is recognized through two main systems — astronomical and meteorological.
In official and scientific contexts, such as calendars or observatory reports, the astronomical autumn begins with the autumnal equinox, which usually falls on September 22 or 23.

However, in everyday life, most people go by the meteorological definition, which starts on September 1. This aligns neatly with the start of the school year, the return of cooler evenings, and the shift in routines — from summer leisure to a busier, more structured pace.

In North America, autumn symbolizes vibrant foliage, pumpkin-flavored everything, harvest celebrations, and cozy family gatherings. Farmers’ markets, fall fairs, and harvest festivals are common across both countries.

The seasonal change is also reflected in media and culture — TV shows return after summer breaks, stores switch to fall décor, and people start talking about the upcoming winter.
So even though the official start of autumn comes with the equinox, for most North Americans, autumn truly begins with September.

B. The United Kingdom

The situation in the UK is similar, though the terminology differs. Here, the term “autumn” is standard, while “fall” is recognized as an Americanism.

The UK Met Office defines meteorological autumn as running from September 1 to November 30. This consistent approach simplifies weather forecasting and climate tracking.

Culturally, however, many people still view the autumnal equinox as the symbolic start of the season.

British autumns are often associated with misty mornings, rainy days, and gradually shortening daylight hours. Nature changes at a gentler pace — green gardens take on amber hues, and cities prepare for winter holidays with cozy lights and early evenings.

C. Australia (Southern Hemisphere)

In Australia, the pattern is reversed. Because the country lies in the Southern Hemisphere, its seasons are opposite to those of the north.

Here, autumn runs from March 1 to May 31, based on the meteorological calendar. This is the most common way Australians define their seasons.

While the astronomical equinox occurs around March 20–21, most Australians recognize the season’s start with the beginning of March.

Autumn in Australia often brings relief from summer heat, grape harvests, and local festivals celebrating seasonal change.
In the southern regions, temperatures cool noticeably and leaves begin to turn, while in the northern tropics, the wet season gradually fades.

D. New Zealand (Southern Hemisphere)

Just like Australia, New Zealand’s autumn begins on March 1 and ends on May 31, following the meteorological calendar. This system is used consistently across weather forecasts, agriculture, and public life.

Astronomical autumn begins slightly later — around March 20–21, when the autumnal equinox occurs, and continues until June 21–22, the winter solstice.

New Zealand’s autumn is known for its mild climate and striking natural beauty. In regions like Central Otago, Queenstown, and Wānaka, trees turn vivid shades of red, orange, and gold — attracting travelers, photographers, and locals alike.

The season also coincides with the grape harvest, an important time for New Zealand’s thriving wine industry.
Days grow shorter but remain comfortably warm, creating a sense of tranquil transition before winter arrives.

Meteorological Autumn Months by Country

When we talk about “autumn months,” we usually refer to the meteorological definition, which divides the year by full calendar months for consistency in weather and climate data.

• United States and Canada (Northern Hemisphere)
  Meteorological autumn runs from September through November — three months that mark cooler temperatures, changing leaves, and harvest time.

• United Kingdom (Northern Hemisphere)
  Similarly, in the UK, autumn also spans September, October, and November.
  When people say “autumn arrives in September,” they’re referring to this period.

• Australia (Southern Hemisphere)
  In Australia, autumn falls in March, April, and May.
  So when November ends in the Northern Hemisphere, Australia is already deep into its own autumn season.

• New Zealand (Southern Hemisphere)
  As in Australia, New Zealand’s autumn covers March, April, and May.
  During this time, temperatures gently cool after summer, days shorten, and landscapes glow with rich, autumnal hues.
  The regions of Central Otago, Queenstown, and Wānaka are especially scenic, known for their golden and crimson trees that draw visitors and photographers.
  Autumn also marks the wine harvest season, celebrated through local food and wine festivals across the country.

Summary Table: Meteorological Autumn by Country

Why the Confusion?

At first glance, the differences between the astronomical and meteorological definitions of autumn might seem minor — yet they are the very reason confusion arises, especially in today’s global information space.

1. Scientific vs. Practical Calendars

The astronomical approach is based on Earth’s position and movement around the Sun, while the meteorological one relies on climate observations and average temperatures.
When scientists refer to the equinox, they’re describing an astronomical event, not the weather itself.
But for most people, weather is what defines a season — cooler air, falling leaves, shorter days — so they tend to follow the meteorological calendar instead.

2. Cultural Influence

Movies, media, and cultural events often bring the feeling of autumn long before it officially begins astronomically.
For example, in the United States, autumn themes — pumpkins, golden leaves, cozy sweaters — start appearing as early as late August.
People respond not to astronomical data, but to symbolic signs of the changing season.

3. Global Differences

Geography adds another layer of confusion.
When autumn arrives in the Northern Hemisphere, it’s spring in the Southern Hemisphere.
So for people in Australia, New Zealand, or Argentina, the word “fall” in September makes little sense.
It’s a reminder that seasonality is relative, shaped by where you live on the planet.

Fascinating Autumn Traditions Around the World

Autumn doesn’t just change the climate — it shapes cultural identity.
Across different countries, this season comes with unique customs, symbols, and festivals that reflect history, gratitude, and the natural rhythm of life.

United States

In the US, autumn is often considered one of the most beloved seasons.
It’s the time of harvest festivals, Halloween, and Thanksgiving — a season filled with family gatherings, comfort food, and warm, earthy décor.

Many towns host parades and county fairs, while tourists travel to the northeastern states to admire the famous fall foliage, where forests explode in shades of red, orange, and gold.

Autumn in America is as much a feeling as a season — a blend of nostalgia, gratitude, and cozy tradition.

Canada

Autumn in Canada shares many similarities with that of the US, yet carries its own charm.
It’s closely tied to Canadian Thanksgiving, celebrated in October, a day devoted to gratitude for the harvest and community.

The season also marks the beginning of hunting, maple syrup collection, and trips to national parks.
The fiery reds, bright oranges, and deep golds of Canadian autumn have become almost a national symbol.

United Kingdom

In the UK, autumn has a quieter, more reflective mood.
Traditional harvest festivals are still observed, offering thanks for the season’s bounty.
In November, Bonfire Night (Guy Fawkes Night) combines historical remembrance with the spirit of autumn through fireworks and gatherings.

British autumns are known for their softness — more mist and drizzle than bold color — yet they have their own charm: a cup of hot tea, woolen scarves, and candlelit evenings are the hallmarks of the season.

Australia

Autumn in Australia is quite unlike that of the north.
It brings a break from summer heat and the end of the grape harvest.
Across the country, people celebrate with wine festivals that blend gastronomy, art, and the outdoors.

April also marks ANZAC Day, a major national day of remembrance for Australian and New Zealand soldiers.
Though not specifically an “autumn holiday,” it falls during this season and adds a tone of reflection and remembrance to the cooler months.

New Zealand

Autumn in New Zealand is a time of tranquility, color, and balance.
Running from March through May, it follows the warmth of summer with gentle cooling and mild, comfortable weather.

The most famous autumn region is Central Otago, home to Queenstown, Wānaka, and Arrowtown.
Arrowtown hosts the Arrowtown Autumn Festival, which attracts both locals and visitors to celebrate the beauty of the season — with leaf-decorated streets, parades, art exhibitions, wine tastings, and farmers’ markets.

Autumn also coincides with the wine harvest season in regions like Marlborough and Gisborne, where vineyards open for tours and tastings.

It’s also the time for agricultural fairs and school holidays, when families travel across the country to enjoy nature’s calm before winter sets in.

This season is often considered one of the most picturesque times of the year — with clear skies, golden landscapes, and a feeling of harmony between people and the land.

Conclusion

Autumn isn’t just a change in the weather — it’s a season of transition when nature, culture, and even our emotions find balance between light and darkness.

In astronomical terms, autumn begins at the moment of the equinox — around September 22–23 in the Northern Hemisphere and March 20–21 in the Southern Hemisphere. Meteorologically, it starts on September 1 or March 1, respectively.

Neither definition is “more correct.” The astronomical one is scientifically precise, while the meteorological one is more practical. Both help us organize the year and understand the natural rhythm of the Earth.

Ultimately, autumn begins differently for everyone — with the scent of rain, the first chilly morning, or the sight of leaves changing color. It doesn’t matter whether it happens in September in North America or March in Australia. What matters is that moment when summer truly fades and the world begins to prepare for winter.

FAQ:

1. When does autumn officially begin?
Autumn begins either on September 1 (meteorologically) or around the autumnal equinox — September 22–23 in the Northern Hemisphere and March 20–21 in the Southern Hemisphere.

2. What’s the difference between astronomical and meteorological autumn?
The astronomical definition is based on the Earth’s position relative to the Sun, while the meteorological definition follows the calendar months and average seasonal temperatures.

3. Why does autumn start in March in Australia and New Zealand?
Because these countries are located in the Southern Hemisphere, where the seasons are opposite to those in the north.

4. Why do Americans say “fall” while the British say “autumn”?
“Autumn” comes from a Latin root and remains traditional in British English, while “fall” — short for “fall of the leaf” — became more common in American English.

5. Why do many people think autumn starts before the equinox?
Because weather changes and cultural cues — like the start of school, fairs, and cooler mornings — appear in early September, well before the astronomical date.

6. Which countries experience autumn first each year?
Australia and New Zealand, where autumn begins on March 1, while spring is still unfolding in the Northern Hemisphere.

In summary:

Autumn is the season of balance.
It begins at different times depending on where you live, yet everywhere it brings the same sense of calm, closure, and renewal. Regardless of what the calendar says, autumn always arrives when light and shadow meet in harmony — a quiet reminder of the connection between humanity and nature.