Don't let "weather-related sickness" get you down before the rainy season! As the seasons of Shōman and Bōshu arrive, why not start self-care by managing your health with a planner?

🌿 24 Solar Terms & Self-Care

Don't Let Pre-Rainy Season "Weather Sickness" Get You Down.
How to Manage Your Health with a Planner During ShōmanShōman and BōshuBōshu Seasons

Barometric pressure changes, autonomic nervous system imbalances, seasonal shifts—your planner can help you anticipate these ailments.

📅 May 2026 ⏱ Approx. 4 min read ✍ Forte Diary
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"Feeling vaguely sluggish" "Heavy head"
It might be weather sickness.

Knowing the transition of the seasons can turn discomfort into "preparation."

Current
Shōman (Small Fullness)
May 21st - June 5th

Late May to June. The sun is summer-like, but rainy days are chilly, and sunny days are humid—are you experiencing such unsettled days?

"Feeling vaguely heavy," "persistent headaches and fatigue," "low mood." These ailments experienced during this period are often caused by weather sickness (tenki-tsu) and autonomic nervous system imbalances. And in fact, by understanding the 24 Solar Terms, you can anticipate and prepare for these ailments.

What exactly are the "24 Solar Terms"?

The 24 Solar Terms (Nijūshi Sekki) is an ancient Chinese calendar system that divides a year into 24 periods, each lasting approximately 15 days, and assigns a seasonal name to each. It was introduced to Japan around the Nara period and has been passed down as wisdom for agriculture and daily life.

✦ What are the 24 Solar Terms?

Based on the sun's movement, these are 24 milestones that finely express the changes of the seasons, such as "Risshun (Beginning of Spring)," "Shunbun (Vernal Equinox)," "Geshi (Summer Solstice)," and "Tōji (Winter Solstice)." They reveal the "rhythm of nature" that calendar dates alone cannot show. They can also be useful in modern life as a clue to anticipate changes in temperature, humidity, and barometric pressure.

From Shōman to Bōshu—The Period When You're Most Likely to Fall Ill

According to the 24 Solar Terms, "Shōman" (Small Fullness) is a time when all things are full of vitality and plants grow rapidly. On the other hand, this period also sees the approach of the rainy season, with barometric pressure beginning to fluctuate significantly.

In the subsequent "Bōshu" (Grain in Ear) (from June 6th), many regions enter the full-fledged rainy season, leading to a triple fluctuation of humidity, barometric pressure, and temperature. This transitional period is said to be the time when the autonomic nervous system is most prone to imbalance, and weather sickness symptoms are most likely to appear.

Common Ailments During the Rainy Season and Seasonal Changes

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Headaches/Migraines

Blood vessels expand due to decreased atmospheric pressure, compressing nerves

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Fatigue/Drowsiness

Parasympathetic nervous system dominance makes the body feel sluggish

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Low Mood

Lack of sunlight and hormonal changes have an impact

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Sleep Disturbances

Difficulty regulating body temperature due to temperature differences

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PMS/Irregular Periods

Barometric pressure fluctuations further disrupt hormonal balance, making symptoms more severe

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Hot Flashes/Swelling

Increased humidity and autonomic nervous system imbalance make body fluid regulation difficult

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Irritability/Anxiety

Women, in particular, are prone to decreased serotonin due to barometric pressure changes, leading to emotional fluctuations

Women, especially those in their 30s to 50s, are more susceptible to the effects of weather sickness due to hormonal fluctuations from menopause or menstrual cycles. Even if you've felt, "Am I the only one suffering this much?" understanding the connection between the seasons and your body can help you objectively accept your discomfort.

✦ What You Should Know

Weather sickness is not "all in your head." It's a genuine bodily reaction triggered when the inner ear detects changes in barometric pressure, leading to an imbalance in the autonomic nervous system. It's said that about 10 million people in Japan suffer from weather sickness.

Forte Diary's Monthly Planner Helps You "Prepare"

This is where the 24 Solar Terms and their explanations in Forte Diary's Monthly Planner come in handy.

When you open your planner, you'll find the names of the solar terms like "Shōman" and "Bōshu," along with subtle descriptions of the climate and natural changes during that period. Since your planner tells you, "The rainy season is approaching," you can anticipate weather changes and prepare to protect your and your loved ones' bodies.

Forte Diary 2026 Monthly Planner June 24 Solar Terms

Forte Diary Monthly Planner (June) — You can note preparations for the rainy season alongside the entry for Bōshu.

Just Write It Down in Your Planner. A "Preparation" List for Weather Sickness and Rainy Season

Try writing these "preparations" in the memo section of Forte Diary's Monthly Planner or the Note section of the Weekly Planner.

📋 Example of Monthly Planner Entry (June)
☁️ Bōshu (6/6~): Watch out for rainy season. Don't push yourself on low-pressure days
💊 Keep headache medicine/motion sickness pills handy (for weather sickness)
🌙 Turn off phone 1 hour before bed (to protect sleep quality)
🍵 Continue morning hot water ritual (to regulate autonomic nerves)
🚶 Go outside on sunny days (replenish serotonin with sunlight)
🌸 Keep track of PMS risk periods (often coincide with low pressure)
👧 Record children's health as a high-risk week (headaches, stomach aches, mood swings)
  • 📅On days with low-pressure forecasts, avoid scheduling important meetings or deadlines. Simply note "☁️ Caution" in your Weekly Planner's calendar.
  • 😴Schedule sufficient sleep as an appointment. Writing "10:30 PM Bedtime" in your planner makes it a commitment.
  • 🌿Record your physical condition in the Note section. Just a quick note like "Feeling heavy-headed today" can help you see patterns in your body.
  • 👧Recording your children's health changes in your planner can also reveal patterns in their bodies, such as "tend to get stomach aches during the rainy season" or "get grumpy on low-pressure days."
✦ For Parents

Children are also affected by weather sickness. If your child seems unusually tired or complains of sudden stomach aches more often during the rainy season, it might be due to changes in barometric pressure and humidity. If you, as a parent, understand the seasonal rhythm, you can take proactive steps in caring for your child. Simply writing "Low pressure forecast this week" in your planner can help you avoid making unreasonable plans.

A Planner Habit That Turns "Discomfort" into "Awareness"

Weather sickness and rainy season ailments are tough because they strike suddenly. But with the lens of the 24 Solar Terms, you can know in advance, "It's time for my body to be unsettled."

With preparation, you can avoid unreasonable schedules. You can rest without blaming yourself. And even amidst discomfort, you can objectively view it as "this is due to the season"—your planner becomes your partner in protecting your body.

✦ FORTE DIARY TIPS

Forte Diary's Monthly Planner includes the 24 Solar Terms and their seasonal descriptions. It's designed so that you notice "the season is here now" every time you open a page. For those sensitive to weather changes, this is a notebook you'll definitely want to make your daily partner.

✦ Forte Diary

Anticipate the seasons, and have good days.

Start a planner habit that harnesses weather changes,
with a Monthly Planner featuring the 24 Solar Terms.

Discover Forte Diary →

Just turn the pages to understand how to use it 📖

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