May is one of the warmer months of the year in Korea, with average highs near 41.6°C and lows around 26.2°C (mean 33.9°C). It is one of the drier months, averaging 38 mm of rainfall and 29% relative humidity across the period.
May is one of the warmer months of the year in Korea. Across 45 years of records, the warmest May in Korea was 1991 — when the month averaged 36.5°C — while the coldest was 2021 at 30.5°C. Typical May days reach 41.6°C with nights near 26.2°C. The long-term trend is cooling, about 0.2°C per decade.
May is one of the drier months in Korea, averaging 38 mm of rainfall. The wettest May on record was 2021 with 115 mm, while the driest was 1991 at 0 mm.
Relative humidity in Korea during May averages 29%. The most humid May was 1990 at 49%, and the least humid was 1991 at 16%.
May receives about 6.8 kWh/m²/day of solar energy in Korea. The sunniest Mays were 1985 and 1986 at 7.6 kWh/m²/day, and the cloudiest was 2025 at 5.6.
Average wind speed in Korea during May is 2.4 m/s. The windiest Mays were 1984 and 2002 at 2.8 m/s, while the calmest was 2025 at 1.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 34.0°C | 34.2°C | 34.0°C | 34.4°C | 32.2°C | -1.8°C |
| Avg High | 42.1°C | 42.0°C | 41.6°C | 42.1°C | 39.3°C | -2.8°C |
| Avg Low | 25.9°C | 26.4°C | 26.4°C | 26.7°C | 25.2°C | -0.7°C |
| Avg Rain | 30 mm | 29 mm | 40 mm | 31 mm | 70 mm | +40 mm |
May temperatures in Korea have fallen by about 1.7°C between 1981–1985 and 2021–2025.
May has ranged from a record low of 19.2°C (1992) to a record high of 47.6°C (1988).
Rainfall in May is one of the drier months, averaging 38 mm, with a wettest year of 115 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 0.4°C per decade while lows rose 0°C per decade, narrowing the gap between day and night.
A quieter season to visit Korea
If your dates are flexible, the more temperate months of February and November tend to be the most comfortable for visiting Korea. That said, May — with days averaging 41.6°C and nights around 26.2°C (mean 33.9°C) and moderate rainfall (38 mm) — can still be rewarding for travellers who don't mind the warmth, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 38.2°C | 32.0°C | 25.7°C | 42.8°C | 21.9°C | 81 mm | 45% | 1.9 m/s | 5.6 |
| 2024 | 41.2°C | 33.9°C | 26.6°C | 46.2°C | 22.3°C | 18 mm | 28% | 2.2 m/s | 6.2 |
| 2023 | 38.1°C | 30.8°C | 23.5°C | 42.5°C | 19.7°C | 92 mm | 42% | 2 m/s | 6.7 |
| 2022 | 41.6°C | 34.2°C | 26.8°C | 44.6°C | 24.0°C | 43 mm | 32% | 2.5 m/s | 6.2 |
| 2021 ❄️ 🌧️ | 36.9°C | 30.5°C | 24.2°C | 40.8°C | 21.7°C | 115 mm | 48% | 2.4 m/s | 5.7 |
| 2020 | 39.7°C | 32.0°C | 24.2°C | 44.3°C | 21.5°C | 69 mm | 39% | 2 m/s | 6.8 |
| 2019 | 42.6°C | 34.7°C | 26.9°C | 45.4°C | 23.5°C | 13 mm | 22% | 2.3 m/s | 6.9 |
| 2018 | 42.1°C | 34.4°C | 26.7°C | 44.9°C | 24.7°C | 30 mm | 30% | 2.4 m/s | 6.4 |
| 2017 | 42.9°C | 35.6°C | 28.3°C | 45.4°C | 24.3°C | 28 mm | 25% | 2.2 m/s | 6.7 |
| 2016 | 40.7°C | 33.6°C | 26.5°C | 44.3°C | 23.1°C | 102 mm | 37% | 2.1 m/s | 6.6 |
| 2015 | 42.6°C | 34.7°C | 26.7°C | 45.4°C | 23.4°C | 8 mm | 23% | 2.4 m/s | 6.8 |
| 2014 | 40.6°C | 33.2°C | 25.9°C | 46.3°C | 22.3°C | 19 mm | 32% | 2.4 m/s | 6.6 |
| 2013 | 43.5°C | 35.0°C | 26.5°C | 46.2°C | 22.4°C | 2 mm | 21% | 2.7 m/s | 7.3 |
| 2012 | 42.3°C | 34.3°C | 26.3°C | 44.9°C | 22.8°C | 10 mm | 19% | 2.4 m/s | 7.1 |
| 2011 | 41.4°C | 34.0°C | 26.7°C | 44.4°C | 23.0°C | 75 mm | 34% | 2 m/s | 6.6 |
| 2010 | 42.1°C | 34.5°C | 26.9°C | 45.4°C | 24.2°C | 22 mm | 30% | 2.4 m/s | 6.6 |
| 2009 | 42.0°C | 34.6°C | 27.1°C | 45.2°C | 24.5°C | 44 mm | 29% | 2.4 m/s | 6.6 |
| 2008 | 41.8°C | 34.3°C | 26.8°C | 43.9°C | 24.3°C | 11 mm | 24% | 2.7 m/s | 6.8 |
| 2007 | 41.1°C | 33.8°C | 26.6°C | 43.7°C | 24.4°C | 32 mm | 32% | 2.4 m/s | 6.4 |
| 2006 | 40.5°C | 33.5°C | 26.5°C | 44.1°C | 24.2°C | 72 mm | 40% | 2.2 m/s | 6.3 |
| 2005 | 41.4°C | 33.4°C | 25.4°C | 45.3°C | 21.5°C | 34 mm | 25% | 2.2 m/s | 7 |
| 2004 | 41.0°C | 33.4°C | 25.8°C | 43.7°C | 20.2°C | 50 mm | 35% | 2.3 m/s | 6.8 |
| 2003 | 42.4°C | 34.3°C | 26.1°C | 44.6°C | 21.5°C | 1 mm | 18% | 2.5 m/s | 6.9 |
| 2002 | 43.5°C | 35.2°C | 26.9°C | 45.9°C | 24.1°C | 35 mm | 23% | 2.8 m/s | 6.9 |
| 2001 | 42.0°C | 34.3°C | 26.7°C | 44.9°C | 24.1°C | 44 mm | 31% | 2.7 m/s | 6.8 |
| 2000 | 40.1°C | 32.9°C | 25.7°C | 44.5°C | 23.2°C | 79 mm | 39% | 2.5 m/s | 6.5 |
| 1999 | 42.1°C | 34.3°C | 26.6°C | 46.1°C | 22.7°C | 27 mm | 27% | 2.5 m/s | 7.1 |
| 1998 | 43.6°C | 35.2°C | 26.9°C | 47.2°C | 22.7°C | 11 mm | 22% | 2.5 m/s | 7.2 |
| 1997 | 40.5°C | 32.7°C | 24.9°C | 44.7°C | 20.5°C | 42 mm | 27% | 2.3 m/s | 6.9 |
| 1996 | 42.8°C | 35.1°C | 27.3°C | 45.1°C | 22.9°C | 6 mm | 20% | 2.4 m/s | 7 |
| 1995 | 40.6°C | 33.5°C | 26.3°C | 45.9°C | 23.4°C | 24 mm | 30% | 2.4 m/s | 6.8 |
| 1994 | 42.9°C | 34.8°C | 26.7°C | 46.4°C | 23.2°C | 12 mm | 24% | 2.3 m/s | 7.4 |
| 1993 | 43.3°C | 35.0°C | 26.7°C | 45.9°C | 24.0°C | 22 mm | 20% | 2.5 m/s | 7.4 |
| 1992 | 41.5°C | 33.3°C | 25.1°C | 44.1°C | 19.2°C | 44 mm | 26% | 2.2 m/s | 7.2 |
| 1991 🔥 | 44.6°C | 36.5°C | 28.3°C | 46.5°C | 25.5°C | 0 mm | 16% | 2.5 m/s | 7.3 |
| 1990 | 38.0°C | 31.5°C | 24.9°C | 42.7°C | 22.2°C | 107 mm | 49% | 2.4 m/s | 6.6 |
| 1989 | 43.2°C | 34.7°C | 26.3°C | 45.5°C | 21.6°C | 5 mm | 21% | 2.7 m/s | 7.2 |
| 1988 | 44.3°C | 35.5°C | 26.7°C | 47.6°C | 22.3°C | 14 mm | 20% | 2.4 m/s | 7 |
| 1987 | 39.7°C | 32.4°C | 25.1°C | 44.1°C | 19.5°C | 55 mm | 32% | 2.1 m/s | 6.8 |
| 1986 | 41.5°C | 33.1°C | 24.8°C | 43.7°C | 21.1°C | 25 mm | 26% | 2.2 m/s | 7.6 |
| 1985 | 43.0°C | 34.9°C | 26.8°C | 45.1°C | 23.9°C | 13 mm | 22% | 2.4 m/s | 7.6 |
| 1984 | 44.6°C | 35.6°C | 26.7°C | 46.6°C | 20.7°C | 18 mm | 17% | 2.8 m/s | 7.5 |
| 1983 | 41.3°C | 33.4°C | 25.6°C | 43.8°C | 22.9°C | 54 mm | 30% | 2.4 m/s | — |
| 1982 | 39.6°C | 32.5°C | 25.5°C | 43.3°C | 21.4°C | 59 mm | 35% | 2 m/s | — |
| 1981 | 41.8°C | 33.7°C | 25.6°C | 45.3°C | 22.9°C | 27 mm | 30% | 2.2 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 41.6°C with lows near 26.2°C (mean 33.9°C), based on 45 years of NASA POWER data.
May averages 38 mm of rainfall in Korea, one of the drier months. The wettest on record was 115 mm in 2021.
The hottest May reached 47.6°C in 1988. The coldest dipped to 19.2°C in 1992.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have fallen by about 1.7°C. Daytime highs moved from 42.1°C to 39.2°C and overnight lows from 26°C to 25.4°C over the same span.
May is one of the warmer months of the year in Korea and one of the drier months, so plan for around 41.6°C daytime highs and 26.2°C at night.
Not quite — May is the 12th coolest month in Korea, averaging 33.9°C.
For May in Korea, pack light, breathable clothing and sun protection, with typical highs of 41.6°C and lows of 26.2°C.
Relative humidity in May averages 29% — relatively dry.
Average wind speed in May is 2.4 m/s. The windiest May on record averaged 2.8 m/s (1984).
The wettest May on record was 2021 with 115 mm. On average, May sees 38 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Korea behaves each May, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for May specifically, along with year-by-year records and how the month has changed over the decades.
