Why the rainy season makes skin break out

Korea's summer monsoon, called jangma (장마) , usually arrives from around late June and lasts into July, although timing varies from year to year. In Seoul it brings days of heavy rain mixed with hot, sticky spells. For skin, the combination of heat, humidity and constant dampness is a reliable recipe for breakouts, even in people whose skin is calm the rest of the year.

Heat increases sebum production, and humid air slows the evaporation of sweat, so oil and sweat sit on the skin longer and mix with sunscreen, makeup and urban grime. Friction then pushes that mixture into pores wherever something rubs: under face masks, cap bands, backpack straps and bra straps. Dermatologists call this pattern acne mechanica .

Damp, warm skin is also an ideal environment for the yeast Malassezia , which can cause fungal folliculitis, often mislabelled 'fungal acne'. It looks like small, uniform, itchy bumps on the forehead, chest or back, and it does not respond to normal acne products. Telling these patterns apart is the first step to treating them well.

What kind of breakout is it?

Not every summer bump is acne. The table summarises the patterns doctors most often see in humid weather and what tends to help each one. Getting the type right matters, because the wrong treatment can make things worse: heavy acne creams can aggravate heat rash, and antibacterial acne washes do little for fungal folliculitis.

Our acne and breakouts guide explains the main acne types in more detail. If you are unsure, a quick examination with a doctor, sometimes with a skin scraping, usually settles the question.

A daily routine for humid weeks

The American Academy of Dermatology recommends washing the face twice a day and after sweating, using a gentle, non-abrasive cleanser and lukewarm water, and avoiding scrubbing, which irritates skin and can worsen acne. In humid weather this simple routine does more than any complicated regimen.

Keep layers light. A water-based or gel moisturiser and a non-comedogenic sunscreen are usually enough; several heavy serums, essences and creams can trap sweat and clog pores. If you wear makeup, choose oil-free, non-comedogenic products and remove them thoroughly at night.

1. Morning: gentle cleanser, light moisturiser, broad-spectrum SPF 30+ sunscreen.
2. Midday: blot rather than wipe; reapply sunscreen if outdoors.
3. After sweating or getting caught in the rain: rinse or cleanse gently and pat dry.
4. Evening: remove sunscreen and makeup, use any acne treatment, then a light moisturiser.
5. Weekly: wash pillowcases, hats and reusable masks; let shoes and bags dry fully.

Small habits that prevent big flares

Many rainy-season breakouts come from what touches the skin. Change out of damp clothes and socks as soon as you can, swap face masks when they become wet, and choose breathable cotton or moisture-wicking fabrics. Wash workout gear after every use and shower soon after exercise.

Hands and phones carry oil and bacteria, so clean your phone screen regularly and avoid resting your chin on your hands. The AAD also warns against popping or squeezing spots, which pushes inflammation deeper and increases the risk of dark marks and scars, a particular concern in warm months when marks darken more easily with sun.

• Carry a spare mask and a small towel on rainy days.
• Tie long hair back and keep heavy hair products off the forehead.
• Use oil-free sunscreen and reapply rather than layering more cream.
• Do not pick or squeeze; cover a tempting spot with a hydrocolloid patch instead.

When to see a doctor

Most summer flares settle with consistent self-care within a few weeks. The checklist shows when it is time to see a doctor instead of trying yet another product. Deep, painful cysts, acne that leaves marks or scars, and bumps that do not respond to standard treatment all benefit from medical care, and early treatment prevents scarring.

A doctor can prescribe topical or oral treatments, confirm or rule out fungal folliculitis, and offer in-clinic care such as gentle extraction, calming light or laser treatment and steroid injections for individual painful cysts. Visitors with an event coming up can read about emergency acne injections before a photoshoot.

Chest, back and shoulder breakouts

Body acne often gets worse in jangma because the chest, back and shoulders sweat heavily and are covered by bags, straps and damp clothing for hours. Spots tend to cluster where straps sit or where a wet shirt clings. Showering soon after sweating, washing with a gentle body cleanser and wearing loose, breathable layers make a noticeable difference within a week or two.

Benzoyl peroxide washes are a common first step for body acne because they can be rinsed off after a minute or two, although they bleach towels and coloured fabrics. If the bumps are small, itchy and all the same size, especially on the upper back and chest, think of fungal folliculitis rather than acne and ask a doctor before buying more acne products. Antifungal shampoos used as a body wash are sometimes suggested once the diagnosis is confirmed.

Men who shave in humid weather often notice bumps along the beard line, which may be ingrown hairs or irritation rather than acne. Shaving with the grain, using a sharp blade and a fragrance-free gel, and moisturising afterwards helps. Our Myeongdong dermatology clinic guide explains how a doctor assesses mixed breakouts on the face and body.

• Shower within an hour of heavy sweating or getting soaked in the rain.
• Rotate backpacks with a cross-body bag to reduce strap friction.
• Sleep in clean, loose cotton and change sheets weekly in humid weeks.
• Rinse benzoyl peroxide washes thoroughly and use white towels.

Clinic treatments for active acne and marks

At Obliv Clinic Seoul Origin, a doctor first identifies the type of breakout using examination and Mark-Vu imaging, which shows inflammation, pores and pigment more clearly than the naked eye. With our Skin Architecture method, active inflammation is calmed first and marks and scars are treated only once breakouts are under control.

For post-acne redness and texture, regenerative treatments such as LDM skin regeneration and boosters can help calm the skin. Brown marks left after summer breakouts often respond to pigment laser with strict sun protection, and established scars may need acne scar treatment such as fractional or pico laser over several sessions.

Visiting Seoul during the rainy season

If your trip falls in jangma, pack light, breathable clothes, a compact umbrella, quick-dry shoes and your usual acne treatments in their original packaging. Hotel rooms will be air-conditioned, which helps with sweat but can leave skin dry and tight; a light gel moisturiser balances both. Our guide to dry hotel air covers that side of the problem.

If you want treatment during the visit, message us on WhatsApp (+82-10-3086-4084) with clear photos. We can tell you what is realistic in your timeframe and which treatments should wait until breakouts settle. The clinic is between Myeongdong and Jongno, about six minutes on foot from Jongno 3-ga and Euljiro 3-ga stations, so you can reach it on a rainy afternoon without a long walk.

Frequently asked questions

Related treatments and guides

Keep reading

• Summer Oil Control Treatments
• Acne Treatment Without Peeling
• Tourist Acne Treatment in Myeongdong
• Hyperpigmentation After Acne Treatment Korea
• Men's Acne Solutions in Seoul

Sources

1. American Academy of Dermatology – Acne: Tips for managing
2. American Academy of Dermatology – 10 skin care habits that can worsen acne
3. Cleveland Clinic – Why does my acne get worse in the summer?