EasyTicket Every year as late June approaches, the news starts warning about “localized torrential rain.” EasyTicket has put together when torrential rain tends to hit, what the official criteria are, and how to prevent damage, all in one place. Knowing this ahead of time means a sudden downpour won’t catch you off guard.
When Does Torrential Rain Happen Most Often?
In Korea, torrential rain is concentrated in monsoon season and just after it ends. According to the Korea Meteorological Administration (KMA), the 2026 monsoon is expected to begin around June 19~21 in Jeju, around June 23~25 in the southern region, and around June 25~27 in the central region.
Expected Monsoon Start and End Dates by Region
| Region | Start | End |
|---|---|---|
| Jeju | Around June 19~21 | Around July 20 |
| Southern region | Around June 23~25 | Around July 24~25 |
| Central region | Around June 25~27 | July 26 ~ late July |
Don’t Let Your Guard Down When the Monsoon Ends
Even after the monsoon officially ends, sudden, localized downpours often continue into early August. In recent years, some of the most intense localized heavy rain has actually hit in the late stages of the monsoon or right after it ends. Stay alert from late July all the way through mid-August.
Torrential Rain vs. Heavy Rain Advisories: What’s the Difference?
You hear the term “torrential rain” often, but the exact criteria can be confusing. Generally, it refers to rainfall of 30mm or more per hour, or 80mm or more in a single day.
Heavy Rain Advisory Criteria at a Glance
| Category | Trigger Criteria |
|---|---|
| Heavy Rain Advisory | 60mm+ expected in 3 hours, or 110mm+ in 12 hours |
| Heavy Rain Warning | 90mm+ expected in 3 hours, or 180mm+ in 12 hours |
| Extreme Rainfall | 50mm+ in 1 hour plus 90mm+ in 3 hours, or 72mm+ in 1 hour |
The Extreme Rainfall criteria have been in effect since June 15, 2023, and when conditions are met, an emergency disaster text alert is sent out (Source: Korea Meteorological Administration).
If you get an emergency disaster text alert, stop what you’re doing outside right away and move to safe, indoor shelter. This matters most of all for anyone living in a basement or semi-basement unit — getting out quickly is critical.
Before Torrential Rain Hits: What to Prepare in Advance
Once a heavy rain advisory is forecast, there’s a lot you can do before the rain actually starts. Preparing ahead of time can dramatically reduce flood damage.
✅ Pre-Rain Preparation Checklist
- Check nearby drains and gutters for blockages
- Prepare sandbags or flood barriers if you’re in a flood-prone area
- Clear drains on verandas and rooftops
- Share an emergency contact list and meeting point with family
- Prepare a flashlight, portable radio, bottled water, and emergency food
- Make sure emergency disaster text alerts are turned on on your phone
💰 Tips for Protecting Your Car and Property
If your car is parked in a low-lying lot or near a stream, move it to higher, safer ground before the heavy rain advisory takes effect. Even if a flooded car is covered by insurance, repairs take a long time and the car’s resale value drops sharply.
What to Do Once Heavy Rain Starts
Once the rain really starts coming down, staying indoors is the safest choice. If you absolutely have to go out, keep the following in mind.
⚠️ Avoid High-Risk Areas
- Stay away from mountains, valleys, streamsides, and breakwaters
- Stop hiking, camping, water play, or fishing immediately
- Avoid low-lying areas, flood-prone spots, and landslide-risk zones
- Don’t enter underpasses or underground parking lots
- Stay away from aging buildings or structures at risk of collapse
🔍 Check Real-Time Information
Keep checking weather conditions and local risk information regularly through TV, radio, the internet, or a disaster-safety app on your phone. The National Disaster and Safety Portal (safekorea.go.kr) has region-specific action guides and shelter information all in one place.
If the road starts flooding while you’re driving, don’t try to force your way through. Once water rises above 30cm, your car can be swept away. It’s safer to leave the car behind and get to higher ground immediately.
How to Check Your Home Safely After Flood Damage
Don’t head straight back into your home just because the rain has stopped. A flooded house carries risks of gas leaks and electric shock, so you need to check it step by step.
📋 Post-Flood Check Order
- Ventilate thoroughly before going inside
- Confirm the gas and electricity breakers are switched OFF
- Have a professional inspect before restoring power and gas
- Check tap water or stored drinking water for contamination before use
- Throw out any flooded food or ingredients (risk of food poisoning)
💡 Don’t Forget to File for Insurance or Support
If you’ve suffered damage from a natural disaster, you may be able to file a claim under storm and flood damage insurance or apply for disaster relief funds. Document the scene with photos and video right after the damage occurs, then report it to your local community service center — after an inspection, you can receive support.
Frequently Asked Questions About Torrential Rain Prep (FAQ)
Q1. Which is more dangerous, a Heavy Rain Advisory or a Heavy Rain Warning?
A Heavy Rain Warning is more dangerous. Based on 12-hour cumulative rainfall, an advisory is issued at 110mm and a warning at 180mm or more. Once a warning is in effect, you should stay indoors and take safety measures immediately.
Q2. I live in a semi-basement or basement unit. How should I prepare?
Installing flood barriers and securing a quick escape route matter most. Place sandbags in front of your windows, and if flooding starts, move to the first floor or higher immediately, before the water rises above knee height.
Q3. I’m not getting emergency disaster text alerts. Is that normal?
Your phone’s emergency alert setting may be turned off. Go to Settings → Notifications → and turn on all the emergency disaster text alert options. Note that safety guidance texts require separate sign-up to receive.
Q4. What should I do if heavy rain suddenly pours down while I’m driving?
Slow down, turn on your hazard lights, and pull over to a safe shoulder or rest area. If your wipers can’t keep up, visibility drops sharply and the risk of an accident rises a lot.
So, how was EasyTicket’s guide to preventing torrential rain and flood damage? Knowing what to expect and preparing ahead can cut your losses significantly. Starting in mid-June, try to make a habit of checking the weather every day. We’re rooting for you and your family to stay safe through this year’s monsoon season.