Unbelievable: 5 Forecasts Unique to Japan

― A Country Where Weather Decides Everything, From Cherry Blossoms to Laundry ―

Watching the morning news, I realize Japan is a country that truly loves talking about the weather.
And it doesn’t stop at just “sunny” or “rainy.”
The day the cherry blossoms bloom, the peak season for autumn leaves, whether laundry will dry,
and even “what clothes to wear today”—the forecast tells us everything.

The announcer delivering it with a straight face.
The weather app that accompanies daily life.
In this country, the weather designs our lives.

Cherry Blossom Forecast: A Country That Can “Predict” Spring

Spring in Japan begins with news of the cherry blossom front.
The Japan Meteorological Agency observes blooming and full bloom, while the Japan Weather Association and Weathernews Inc. release nationwide forecast maps.
News broadcasts show daily footage of a pink band moving northward.

The predicted date for cherry blossom blooming and locations currently in full bloom are marked with a 🌸 symbol. — The predicted date for cherry blossom blooming and locations currently
in full bloom are marked with a 🌸 symbol.

Across the country, designated cherry trees called “standard trees” serve as observation points.
In Tokyo, the Somei-Yoshino cherry tree at Yasukuni Shrine is the benchmark.
When 5-6 buds open, it’s “blooming”; when 80% are open, it’s “full bloom.”
Measuring the season with numbers is quintessentially Japanese precision.

People plan their hanami outings based on this information, travel sites feature special sections, and social media buzzes with cherry blossom maps.
Science moves emotions—that’s the starting line of spring in Japan.

Autumn Foliage Front: News That Paints the Season

As autumn arrives, the “autumn foliage front” emerges, mirroring the cherry blossom front.
The Japan Weather Association and Weathernews predict peak foliage dates across Japan based on temperature, sunshine hours, and precipitation. Television and apps simultaneously release “color change maps.”

The areas painted gray have already shed their leaves, while the areas painted red are currently at their peak for autumn foliage. As the colors shift closer to orange, the prime viewing period gradually shifts later. — The areas painted gray have already shed their leaves, while the areas painted red are currently at their peak for autumn foliage.
As the colors shift closer to orange, the prime viewing period gradually shifts later.

However, this isn’t a “declaration” like cherry blossom forecasts.
It’s more like a forecast to “watch nature’s pace together.”
While inns and tourist spots prepare in advance,
the phrase “Now is the peak viewing time” still holds the power to move people.

Japanese news programs essentially “program” the seasonal transitions themselves.
Weather treated like art—that is this country’s meteorological culture.

Laundry Forecast: How Weather Shapes Daily Life

In Japan, weather forecasts routinely include comments like “It’s a good day for laundry.”
This is based on a metric called the “Laundry Index,” calculated using sunlight hours, humidity, and wind speed.
It provides numerical values indicating “dries well” or “dries poorly” for each region.

Multiple icons indicate whether today is suitable for laundry (outdoor drying).

Japan has a long-standing culture of drying laundry outdoors.
There’s a sense that drying in sunlight is the cleanest method,
and “hanging laundry on a sunny day” is a fundamental household task.
In urban areas, apartment rules often prohibit outdoor drying,
and many choose indoor drying for security or privacy reasons.
Meanwhile, in rural and suburban areas, the sight of laundry against the blue sky remains a daily norm.

Additionally, Japanese weather forecasts often include not just laundry indices,
but also forecasts for yellow sand and PM2.5 dispersion.
PM2.5 is an air pollutant known as fine particulate matter,
which can irritate the respiratory system and eyes.
In early spring, yellow sand sometimes drifts in from the Chinese mainland,
and even on sunny days, forecasts might advise, “The air quality is poor today, so avoid drying laundry outside.”

PM2.5 concentrations are displayed using dots of different colors. Based on this, Japanese people decide whether to hang laundry outside or wear masks when going out.

In this environment, Japan has even seen the emergence of detergents specifically designed for indoor drying.
They are formulated to suppress odors and ensure clothes dry cleanly even in humid indoor conditions.
Unlike many countries overseas that rely heavily on dryers,
Japan is a country where even laundry converses with the weather.

Clothing Forecast: Decide by Feeling, Not Temperature

“Today calls for long sleeves plus a cardigan.”
Most Japanese have heard this phrase in news or apps.
It’s the “clothing forecast.”
It calculates the “feels-like temperature” based on temperature, humidity, and wind speed,
telling you what clothing will be comfortable.

In the news, a clothing forecaster tells us whether we need a jacket based on the temperature.

While overseas forecasts might end with “Today is 18 degrees,”
in Japan, they tell you “At 18 degrees, maybe a light coat?”—considering how it feels.
This nuance, straddling science and sensibility, is the essence of Japan’s weather culture.
A forecast that conveys sensation, not just numbers—that’s the charm of the clothing forecast.

Column: The “Other Forecast” We’d Rather Not Hear

And in Japan, there’s another “forecast” everyone knows about but would rather not hear.
That’s the Earthquake Early Warning.
When the initial seismic waves (P-waves) are detected, smartphones nationwide sound an alarm simultaneously within seconds.
Docomo, au, SoftBank, Y!mobile, Rakuten Mobile—all carriers participate,
delivering life-saving information faster than TV or radio.

Of course, breaking news alerts will be broadcast, but if an earthquake of a certain magnitude is predicted, your mobile phone will emit a loud, shrill alarm just before the earthquake strikes (3 to 10 seconds prior).

Whether it’s forecasts for cherry blossom blooms or alerts for earthquakes,
both represent the two sides of Japan’s relationship with nature.
This country’s forecasts embody both beauty and crisis management.

Pollen Forecast: The Nation Quantifying Spring’s Enemy

Come February, weather maps begin to turn yellow.
The “Pollen Forecast”—the season of cedar pollen arrives with spring.
Based on dispersal data jointly released by the Japan Meteorological Agency, the Ministry of the Environment, and Weathernews,
news reports announce things like “Pollen season begins in Kanto” or “Peak season in Tohoku.”

Japanese cedar pollen allergy affects 38.8% of the population (2019 data), meaning roughly one in three people suffer from cedar pollen.

Seeing these forecasts, people buy masks, get medicine, and turn on their air purifiers.
Both the joys and the hardships of spring exist entirely “within the forecast.”
Weather forecasts help us feel the seasons, and simultaneously prepare for them.

We always start with the weather.

Japanese people love talking about the weather.
But it’s not because they have nothing else to say.
It’s the shared awareness that “we’re experiencing the same season” that brings comfort.

“It’s perfect laundry weather today, isn’t it?”
“The autumn leaves are really starting to look beautiful.”
Such simple phrases encapsulate this country’s culture and kindness.

Weather isn’t just news; it’s the gateway to conversation connecting daily life and emotions.
Cherry blossoms, autumn leaves, laundry, clothing choices, pollen—
Japanese people live everything alongside the weather.

Source:
Japan Meteorological Agency (JMA)
Japan Weather Association (JWA)
Weathernews Inc.

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