KMA heavy rain advisory thresholds
| Alert | 3-hour total | 12-hour total |
|---|---|---|
| Advisory | ≥ 60 mm expected | ≥ 110 mm expected |
| Warning | ≥ 90 mm expected | ≥ 180 mm expected |
Either condition triggers the alert.
Urban floods are decided in shorter windows
- National advisories use 3- and 12-hour totals, nationwide
- Underpasses and semi-basements flood first in 15–60 minutes of intense rain
- That is why Seoul runs its own flood advisory and warning criteria
Seoul flood advisory and warning criteria
| Level | Criterion |
|---|---|
| Flood advisory | ≥ 55 mm per hour or ≥ 20 mm in 15 minutes |
| Flood warning | ≥ 15 cm at road water-level gauges |
What the field needs
- 1-minute rainfall observed near risk points
- 15-minute and hourly totals compared with thresholds in real time
- Alerts to staff the moment thresholds approach
Sources
- 호우특보 발효 기준 보도 (호우주의보·경보) — 세계일보, 2024
- 폭우참사 막는 서울시… 침수 예·경보제 전국 첫 실시 — 서울신문, 2023
- 호우특보 기준의 지역 특성 반영 한계 — 한국산학기술학회 학술발표, 2022
