Busan in May
What to expect
Busan is in late spring during May, a shoulder-season stretch where conditions can nudge warmer or cooler week to week. It generally feels mild and comfortable, and a gentle drop-off once the sun goes down. Conditions tend to feel steady, which makes planning simple. Daylight stays generous for longer outdoor plans.
May in context
How it compares to the rest of the year in Busan.
Monthly climate breakdown
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 14 h
- UV index (max)
- 8
- Typical sun hours
- 05:20 - 19:20
Rain & Snow
- Total rain
-
- Rainy days
- 10 days
- Cloud cover (avg)
- 59%
Humidity & Wind
- Humidity (avg)
- 77%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Day 15 selected for May. Typical high 19.8°C and low 14.5°C.
Typical disruptions in May
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in May.
Rain disruption Measures: Likely rain disruption days. Observed about 16% of days (5.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
5.0 days / month
~16% of days
Why this matters
- Expected days 5.0 days / month
- Probability ~16% of days
- Intensity Up to ~56mm (P95)
Rain disruption risk appears on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Washout risk Measures: Washout day risk. Observed about 15% of days (4.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.6 days / month
~15% of days
Why this matters
- Expected days 4.6 days / month
- Probability ~15% of days
- Intensity Up to ~58mm (P95)
Washout conditions are possible on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 12% of days (3.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
3.8 days / month
~12% of days
Why this matters
- Expected days 3.8 days / month
- Probability ~12% of days
- Intensity Up to ~97km/h (P95)
Strong gusts are possible on ~4 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 11% of days (3.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
3.5 days / month
~11% of days
Why this matters
- Expected days 3.5 days / month
- Probability ~11% of days
- Intensity Up to ~60mm (P95)
Heavy rain is possible on ~4 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Stormy conditions Measures: Storm-impact proxy days. Observed about 8% of days (2.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
2.6 days / month
~8% of days
Why this matters
- Expected days 2.6 days / month
- Probability ~8% of days
- Intensity Up to ~99km/h (P95)
Stormy conditions are possible on ~3 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 6% of days (1.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.8 days / month
~6% of days
Why this matters
- Expected days 1.8 days / month
- Probability ~6% of days
- Intensity Up to ~98% (P95)
Fog-likely conditions are possible on ~2 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Show all disruptions (16 more)
Very heavy rain Measures: Very heavy rain days (>=25mm). Observed about 5% of days (1.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.7 days / month
~5% of days
Why this matters
- Expected days 1.7 days / month
- Probability ~5% of days
- Intensity Up to ~75mm (P95)
Very heavy rain is possible on ~2 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Washout run Measures: Multi-day washout runs. Observed about 1.0 days/month in May. Historical risk signal only, not a day-by-day forecast.
1.0 days / month
Probability unavailable
Why this matters
- Expected days 1.0 days / month
- Probability —
- Intensity Up to ~67mm (P95)
Multi-day washout runs are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Severe gusts Measures: Severe gust days (>=80 km/h). Observed about 2% of days (0.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.5 days / month
~2% of days
Why this matters
- Expected days 0.5 days / month
- Probability ~2% of days
- Intensity Up to ~116km/h (P95)
Severe gusts are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Extreme rain Measures: Extreme rain days (>=50mm). Observed about 1% of days (0.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.5 days / month
~1% of days
Why this matters
- Expected days 0.5 days / month
- Probability ~1% of days
- Intensity Up to ~99mm (P95)
Extreme rain is possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 56% of days (17.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
17.3 days / month
~56% of days
Why this matters
- Expected days 17.3 days / month
- Probability ~56% of days
- Intensity Up to ~73km/h (P95)
Gusty conditions are possible on ~17 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 53% of days (16.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
16.5 days / month
~53% of days
Why this matters
- Expected days 16.5 days / month
- Probability ~53% of days
- Intensity Up to ~100% (P95)
Cloudy skies are possible on ~16 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
High humidity Measures: High humidity days (RH >=80%). Observed about 42% of days (13.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
13.0 days / month
~42% of days
Why this matters
- Expected days 13.0 days / month
- Probability ~42% of days
- Intensity Up to ~94% (P95)
High humidity is possible on ~13 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Wet days Measures: Wet days (>=0.1mm). Observed about 37% of days (11.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
11.5 days / month
~37% of days
Why this matters
- Expected days 11.5 days / month
- Probability ~37% of days
- Intensity Up to ~46mm (P95)
Measurable rain is possible on ~12 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 35% of days (10.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.8 days / month
~35% of days
Why this matters
- Expected days 10.8 days / month
- Probability ~35% of days
- Intensity Up to ~100% (P95)
Mostly cloudy skies are possible on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 28% of days (8.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
8.6 days / month
~28% of days
Why this matters
- Expected days 8.6 days / month
- Probability ~28% of days
- Intensity Up to ~20h (P95)
Several rainy hours are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 19% of days (6.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
6.0 days / month
~19% of days
Why this matters
- Expected days 6.0 days / month
- Probability ~19% of days
- Intensity Up to ~21h (P95)
Wet-most-of-day conditions are possible on ~6 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 18% of days (5.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
5.7 days / month
~18% of days
Why this matters
- Expected days 5.7 days / month
- Probability ~18% of days
- Intensity Up to ~100% (P95)
Overcast skies are possible on ~6 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 6% of days (1.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.8 days / month
~6% of days
Why this matters
- Expected days 1.8 days / month
- Probability ~6% of days
- Intensity Up to ~98 (P95)
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~2 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Humid days Measures: Humid days (dew point >=18C). Observed about 2% of days (0.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.5 days / month
~2% of days
Why this matters
- Expected days 0.5 days / month
- Probability ~2% of days
- Intensity Up to ~20°C (P95)
Humid conditions are possible on ~0 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Convective risk Measures: Convective storm risk proxy. Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~20°C (P95)
Convective risk signal appears on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 1% of days (0.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~31km/h (P95)
Breezy conditions are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Frequently asked questions
Is May a good time to visit Busan?
Typical May days in Busan reach highs of 20°C (68°F) with nights around 14°C (57°F). It usually feels mild by day and cool after dark. Overall, May sits in the middle of the Busan climate range.
What are temperatures like in May?
Daytime temperatures in May typically peak near 20°C (68°F), while nights drop to around 14°C (57°F). Expect mild afternoons and cool evenings.
How much does it rain in May?
Rainfall in May averages 123 mm (4.8 in) across roughly 10 days. Overall it is a quite rainy time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in May?
You can expect about 14 hours of daylight in May. Sunrise is typically around 05:20 and sunset near 19:20. You get long days with comfortable amounts of daylight.
How strong is the sun in May?
UV levels frequently reach very high levels (around 8), so strong sun protection is essential, especially around midday.
Is it windy in May?
In May, average wind speeds are around 12 km/h (7 mph), with gusts on the windiest days reaching about 62 km/h (39 mph). On the ground, it is it is a notably windy place, and strong gusts are fairly common.