Here’s Why You Should Get a Portable Dehumidifier This Summer 2025

The longest day of the year is more than just a moment of solar spectacle—it’s a turning point. As the Summer Solstice draws near, sunlight lingers longer, temperatures rise steadily, and a hidden shift begins to take place indoors: the rise of oppressive humidity.

In 2025, the Summer Solstice will occur on Friday, June 20 in the Northern Hemisphere. According to Space.com, it will occur at approximately 10:42 p.m. EDT on June 20. It marks the official beginning of summer, when the sun reaches its highest point in the sky, and the days are warm, bright, and—unfortunately—often muggy.

With soaring temperatures come skyrocketing humidity levels indoors, which can lead to discomfort, mold growth, and even poor air quality. For many homeowners and facility managers, the Summer Solstice also kicks off their search for a reliable dehumidifier.

But what exactly is the Summer Solstice, and why does it matter to your indoor air quality?

In this blog, we’ll explore more about this event, its impact on your home, and how you can stay dry and healthy through the hottest months of the year.

What Is the Summer Solstice?

The Summer Solstice is the longest day of the year. During this day, the Earth receives its maximum hours of sunlight.

This happens because of Earth's 23.5-degree axial tilt. As the planet orbits the sun, this tilt causes different regions to receive varying sunlight intensity. On this day, the Northern Hemisphere experiences the most daylight hours of the entire year.

Fun Facts about the Summer Solstice:

• The word “solstice” comes from Latin, meaning “sun standing still.”
• Ancient cultures saw the solstice as a sacred time, celebrating fertility, growth, and the sun’s peak power.
• Some regions of the northern Arctic Circle can experience a phenomenon called the “midnight sun,” where the sun remains visible at midnight. Also known as a polar day, this happens because of the Earth’s tilt, causing the sun to be above the horizon for 24 hours a day at our planet’s poles. The midnight sun commonly occurs during summer months north of the Arctic Circle.

While the solstice marks the longest day, it also kicks off a steady climb in heat retention and air moisture. Today, it’s both an astronomical milestone and a seasonal signal: summer heat—and humidity—have officially arrived.

Cultural Celebrations and Observances

Aside from being an astronomical event, the Summer Solstice has been culturally and spiritually significant around the world since the Neolithic period.

Here are a few examples of how the Summer Solstice is celebrated in various countries globally:

Stonehenge, United Kingdom

The Stonehenge is a globally popular prehistoric monument located in Wiltshire, England. Built in six stages between the 3000 and 1520 BC, the name of this monument derives from the Saxon term “stan-hengen,” which means “stone hanging” or “gallows,” likely because of the Stonehengen’s resemblance to trilithons. While the original creator of Stonehenge is unknown, the site is said to have been built and used for ceremonial and religious purposes.

During the Summer Solstice, thousands of people gather at the Stonehenge to witness the sunrise’s perfect alignment with the monument’s layout. Attending at the Stonehenge at the day of the Summer Solstice is not just a mere part of a travel bucket list, it’s a full spiritual experience that encourages people into personal reflection, setting intentions, celebrating life, and connecting with the divine and their own spirituality.

Eastern Europe

In places like Ukraine and Poland, Kupala Night is celebrated around the Summer Solstice. This traditional Slavic holiday is celebrated to honor and worship the forces of nature.

Kupala Night honors both pagan and Christian traditions and is associated with the birth of John the Baptist, a prominent Jewish preacher and prophet who was also known as the forerunner of Jesus Christ.

Today, Ukraine rarely celebrates this holiday based on the known traditions. However, they still honor important rites and customs, especially those with symbolic meanings.

Scandinavia

In the Scandinavian regions, Midsummer is a popular holiday celebrating the traditional midpoint of the harvest season and the summer solstice. In Sweden and Finland, it’s a joyful celebration marked by traditional activities such as maypole dancing, flower crowns, bonfires, and having feasts.

The countries Denmark and Norway celebrate it as Sankt Hans Aften or St. John’s Eve. Similar to Eastern Europe’s Kupala Night, Sankt Hans Aften also has a mix of pagan and Christian elements, as the holiday is traditionally celebrated with bonfires to ward off evil spirits while honoring St. John the Baptist.

International Yoga Day 2025

Yes, you’re reading that right. The International Yoga Day and the Summer Solstice are interconnected.

Yoga originated in India over 5,000 years ago as a holistic discipline for the pursuit of self-mastery. In Hindi culture, it is believed that when Lord Shiva, historically considered the first yogi or Adiyogi (the originator of yoga), began sharing his knowledge of yoga with the world during the Summer Solstice.

Today, we know yoga as a wellness activity that promotes all physical, mental, and emotional wellness—and it is celebrated annually by the world, especially by yogis, with the Summer Solstice.

Why Humidity Peaks After the Solstice

The Summer Solstice marks the start of a domino effect in the atmosphere. While it signals the longest day of the year, it also begins a powerful chain reaction: prolonged sun exposure, warmer surfaces, and intensified evaporation from soil, lakes, and plants. This combination leads to a gradual but undeniable rise in air moisture.

Even though temperatures may not hit their peak until mid-July or early August, humidity levels often start climbing immediately after the solstice. The Earth's surface continues to absorb solar energy long after the solstice passes, and this heat retention drives evaporation across urban, rural, and coastal areas.

The result: Stuffy indoor spaces, windows dripping with condensation, and air that feels heavy, even when your thermostat says it shouldn’t be.

Summer Humidity and Its Effects

Humidity might be invisible, but its effects are clear. When indoor relative humidity exceeds 60%, it opens the door to a host of problems:

Health Issues

High humidity acts like a breeding ground for mold spores, dust mites, bacteria, and mildew. These allergens flourish in moist conditions, triggering asthma, sinus infections, and respiratory issues in both adults and children. Prolonged exposure can also weaken the immune system, intensify eczema, and cause frequent headaches because of poor oxygen exchange in the lungs.

And while the health risks are especially pronounced for those with sensitivities, even healthy individuals may experience sleep disruption, fatigue, and brain fog in a persistently humid home. This is because your body’s ability to cool itself through sweat becomes inefficient when the air moisture is high.

Structural and Property Damage

Humidity affects your home’s structure and contents. Wood expands and warps, causing issues with floors, doors, and cabinetry. Paint may peel or bubble due to underlying moisture, and electronics are especially vulnerable to corrosion when exposed to long-term damp conditions.

Musty Smells

Persistent humidity in dark, unventilated spaces creates a distinct, musty smell that clings to clothing, linens, furniture, and anything porous. Even if mold isn’t yet visible, the odor is an early warning sign of air stagnation and microbial buildup. This is most common in closets, under-stair storage, attics, crawl spaces, and garages.

Mold Growth

Mold tends to form in bathrooms, closets, basements, or even corners of bedrooms—anywhere that’s prone to trapping moisture. Once it starts growing, mold can spread quickly and require professional remediation to fully eliminate, often at great expense.

Here’s how it happens: Mold starts forming when moisture lingers too long, especially in temperatures around 70-90°F. Initially, it may appear as black spots or fuzzy discoloration near baseboards or behind furniture. But behind walls and inside HVAC systems, colonies can grow out of sight.

Mold exposure is highly dangerous, and has been linked to respiratory illness, neurological symptoms, and chronic inflammation. And once it takes hold, it often requires expensive professional mold remediation, especially if it spreads through your home’s ductwork or insulation.