A heatwave is a natural disaster in which extremely hot weather continues for several days during summer. Intense heat can cause your health to deteriorate suddenly, so it is especially important for children, older adults, pregnant women, and people who work outdoors to check weather information in advance and prepare. This guide walks you through everything step by step, from recognising a heatwave situation to indoor and outdoor preparation tips and emergency response.

How Do You Check the Heatwave Situation?

From June 2026, the Korea Meteorological Administration (KMA) will add a new “Heatwave Major Alert” level to its existing two-level system of “Heatwave Advisory” and “Heatwave Warning,” creating a three-level structure. A “Tropical Night Advisory” will also be newly introduced to address health impacts from nighttime heat. The current standards are shown below; please check the KMA Weather Alert Issuance Standards page for the latest information on changes from June 2026 onwards.

Alert typeIssuance criteria
Heatwave AdvisoryWhen the daily maximum temperature is forecast to reach 33°C or above for two or more consecutive days
Heatwave WarningWhen the daily maximum temperature is forecast to reach 35°C or above for two or more consecutive days
Heatwave Major Alert (new from June 2026)When the apparent temperature is forecast to reach 38°C or above, or the air temperature 39°C or above, for one or more days
Tropical Night Advisory (new from 2026)When health risks from nighttime heat are expected (check the KMA for the latest criteria)

In addition, when the overnight minimum temperature stays at 25°C or above, this is called a tropical night. Because the heat does not ease even at night, it becomes hard to sleep and the body cannot recover, making the situation more dangerous.

During summer, check the weather frequently through TV, radio, and the internet. You can check currently active alerts and the areas they cover in real time on the KMA Weather Nuri website (Korean). Because alert criteria can change over time, please confirm the latest information with 1345 (Immigration Contact Center) or your local Korea Immigration Service office before making any decisions.

How to Prepare for a Heatwave

Staying hydrated

Drink water regularly even if you do not feel thirsty. On hot days, your body can already be close to dehydration before you feel thirst.

Indoors

  • Block direct sunlight by fitting curtains, fabric, or insulating film on windows.
  • If you do not have air conditioning, block as much sunlight as possible, open windows and doors, and use a fan to keep air circulating.
  • When using air conditioning, keep the indoor temperature at 26 to 28°C. Setting it too low can cause “air conditioning sickness” (naengbangbyeong), a condition characterised by headaches, fatigue, and a runny nose.
  • Prepare a torch, emergency food, a hand fan, and a portable radio in case of a power outage.
  • Store bottled water in case of a water supply disruption, and fill the bathtub with water in advance for non-drinking use.

Outdoors

  • When a heatwave alert is in effect, reduce outdoor activity as much as possible. Between 2 p.m. and 5 p.m. is the hottest part of the day, so it is best to avoid outdoor work during these hours.
  • If you must work outside, taking short, frequent breaks is more effective at preventing heat fatigue than taking fewer, longer breaks.
  • When going out, wear lightweight, light-coloured clothing, a wide-brimmed hat, and use a parasol and sunscreen (sunblock). Always carry a water bottle.
  • Instead of caffeinated drinks such as coffee or energy drinks, or alcoholic beverages, drink water and sports drinks (electrolyte drinks). Caffeine and alcohol can worsen dehydration.
  • If you work in a livestock barn or a plastic greenhouse (vinyl house), ventilate frequently and spray water on the floor and walls to bring the temperature down.

Using a cooling shelter

If you are out and about or do not have cooling equipment at home, use a nearby cooling shelter (무더위 쉼터, mudeoui swimteo) during the hottest hours of the day. Cooling shelters are facilities in the local community such as community centres, libraries, and senior centres, and they are free for everyone to use.

You can find shelter locations on the National Disaster Safety Portal (Korean). After visiting the site, go to Disaster Status > Regional Situation > Cooling Shelters to find shelters near you. As the menu layout may change, try searching for “무더위쉼터” on the site or contact 1345 for assistance.

As also explained in Causes and Prevention of Sleep Disorders, Self-Check and Hospital Information, tropical nights can significantly reduce sleep quality. If you experience persistent sleep problems during a heatwave period, consulting a medical professional is a good idea.

When the Heat Makes You Unwell

During a heatwave, the following symptoms and conditions can occur. If you notice any of them, stay calm and respond carefully.

First step: Find out in advance where your nearest medical facilities are and note their contact details.

General initial response

If heat-related symptoms such as dizziness, nausea, headache, or muscle cramps appear:

  1. Move the person to a shaded or cool place and let them rest.
  2. Loosen any tight clothing, and if clothing is soaked with sweat, change it for dry clothing.

Response by symptom

Symptom or conditionHow to respond
Heat rash (prickly heat)Do not scratch, as scratching will worsen the skin. If symptoms are severe, see a doctor.
BurnsIf blisters form, cover them with gauze to protect the area. Do not burst blisters, as there is a risk of bacterial infection.
Heat crampsHave the person drink water with a small amount of salt dissolved in it.
Heat exhaustion (rising body temperature, fatigue)If the person is conscious, give them water to drink. Once body temperature returns to normal, wrap them in clothing or a blanket to remove the chill.
Heatstroke (high body temperature with loss of consciousness)Call 119 immediately. After calling, wet the body with lukewarm water to bring the temperature down. If the person is conscious, have them sip cool water slowly.

Extreme heatwaves and disaster situations can also cause mental stress and anxiety. If you are struggling emotionally or feeling anxious beyond physical symptoms, please refer to Suicide Prevention and Mental Health Information for Refugees and Migrants or Anxiety Disorder Symptoms, Treatment, and Mental Health Counselling Information for Foreigners.

If a Wildfire Breaks Out During a Heatwave

On days of severe heat, you may encounter a wildfire while hiking or camping. Keep the following tips in mind.

If you discover a wildfire

  • Report it immediately.
    • Fire service: 119
    • Police: 112
    • Korea Forest Service wildfire hotline: 042-481-4119
  • If the fire is small, you may be able to smother it with a jacket or coat, but if the flames are large, do not attempt to fight the fire. Evacuate immediately to a safe, open area such as a field, farmland, or open lot.

If you are trapped by fire

  • Evacuate to lower ground. Wildfires spread upward rapidly, so avoid higher ground.
  • Determine the wind direction and move in the opposite direction to the way the fire is spreading.
  • Areas where the fire has already passed and burned out, roads, and spots behind large rocks offer relative safety as there is little remaining fuel.

If there is no time to evacuate

  1. Turn your back to the wind and clear away any flammable material nearby, such as fallen leaves and branches.
  2. Call 119 or 112 to report your location and request rescue.
  3. Cover your face with clothing or fabric, lie as flat as possible against the ground, and wait for rescue.

Figures and criteria may change over time. Before applying or making enquiries, please confirm the latest information with 1345 (Immigration Contact Center) or your local Korea Immigration Service office.