30YearWeather
Jeju Island, April 20
Jeju Island street view during April
Historical Weather Analysis

Jeju Island Weather on April 20 — Best Time to Visit?

Based on 30 years of historical data, we have the answer.

cloudy

17.9°C

High

12.2°C

Low

27%

Rain

🌤️ Feels like 17.9°C

partly-cloudy-day
YES, GOOD CHOICE

April 20 is generally a great time to visit Jeju Island. While there is a slight chance of rain (27%), showers are usually brief. Expect comfortable 18°C weather. It's a lively time to explore Jeju Island, with most attractions operating at full capacity.

Currency

KRW

South Korean won

Language

Korean

Driving

Right side

Safety

High Safety

GPI: 1.779

Jeju Island Weather Forecast for April 20

"Mild & Comfortable. Expect average highs of 17.9°C. 27% chance of rain."

What to Wear in Jeju Island in April

Based on historical data for April 20, Jeju Island typically experiences temperatures between 12.2°C and 17.9°C. We recommend packing light jacket, long pants to stay comfortable. With a 27% chance of rain, keeping a raincoat or umbrella handy is a smart move.

Complete Packing Guide

Weekly breakdown & essential items for Jeju Island

View Guide

Smart Suitcase

  • Light Jacket
  • Long Pants

Average High

extreme-hot

17.9°C

Daytime Peak

Average Low

extreme-cold

12.2°C

Nighttime Low

Feels Like

partly-cloudy-day

17.9°C

🌤️ Feels accurate

Rain Chance

rain

27%

Avg 2.9mm if it rains

Cloud Cover

cloudy

65%

Overcast

Pressure

pressure

1014.4 hPa

Medium volatility

Jeju Island Weather Conditions & UV Index

Weather Confidence

30-year variance analysis

100%Highly Predictable

Based on 10 years of data

Temperature
±1.8°CStable
Precipitation
14-41%Predictable

🎯 This date historically delivers consistent weather 100% of the time. Safe to plan outdoor activities with confidence.

Sun Exposure

UV Index & Safety Guide

4.1Moderate
036811+

Protection Needed

SPF 30 recommended

Safe Sun Windows
Morning

05:00 - 10:00

Afternoon

16:00 - 19:00

Time to Sunburn

Type I-II

🔴 20 min to burn

Type III-IV

🟡 30 min to burn

Type V-VI

🟢 50 min to burn

UV estimate based on latitude, season & cloud cover. Actual UV may vary.

Outdoor Comfort

How pleasant is it outside?

80Excellent
TemperatureMild
HumidityMuggy
WindBreezy

Dew Point

13.6°C

Pleasant

Heat Stress

Low

No heat warning

😊 Best outdoor time:
Any time during daylight hours

Marine Conditions

Water Temp
15.9°C
🥶 Polar Plunge
Avg daily surface temperature
Surf Conditions
0.74m
🌊 Fun Waves
Max daily wave height
Advisories

Marine Life

No special warnings. Enjoy the swim!

Swim Index

❄️ Cold Water Hazard

Travel & Logistics Insights

Local Calendar

Business Day

Standard hours in South Korea

Flight Traffic

Busy

67/100 pressure index

Health Advisory

Required

2 vaccines • View Details →

Landing Slots

~165

Daily arrival options (inc. codeshare)

Sunrise, Sunset & Wind in Jeju Island

Daylight & Sun

Solar Elevation Cycle

🌅 Sunrise

05:59

☀️ Noon

12:34

🌇 Sunset

19:08

⏱️ Daylight

13h 9m

Golden Hour
Morning05:59 - 06:32
18:35 - 19:08Evening

Wind Speed

wind

16.8 km/h

Gentle breeze

Sunshine

clear-day

8.3 hrs

Direct Sun (Cloud-free)

Humidity

humidity

76%

Humid / Damp

Travel Intelligence

Exclusive flight analytics & health data for Jeju Island

Smart Flight Estimator

Airport-to-Airport Logistics

unlock smart flight estimates

Add your home location in settings to see airport details.

Travel Health & Safety in Jeju Island

Travel Comfort Index

Real-time tourism conditions

Weather Quality

⛅ Good

78/100

Tourist Crowds

🟡 Busy

70/100

Price Level

💰💰 Moderate

75/100

Health & Wellbeing

Meteo-Health Forecast

85Score
Atmospheric Pressure1014.4 hPa
Volatility:Medium
Migraine RiskMedium

Moderate fluctuations. Some sensitivity possible.

Joint Pain RiskLow

Weather unlikely to affect joint pain.

Fishing IndexFair

Moderate fish activity expected.

Air Quality Forecast
41AQI
Good
PM2.5 Concentration21.8 µg/m³

Air quality is excellent. Perfect for outdoor activities.

Regional Safety Profile

Low

Seismic Activity

Rare minor tremors. Buildings are earthquake-resistant.

Total events (30y):1
In Apr (30y):0
💡 Very rare tremors. Standard travel precautions apply.
Very High

Typhoon Risk

Year-round risk present

Travel Alert: This region has elevated natural risks. We recommend registering with your embassy and keeping emergency numbers handy.

"According to 30YearWeather's analysis of 30 years of NASA satellite data, Jeju Island on April 20 averages 17.9°C with a 27% precipitation probability. Wedding/Outdoor Event Score: 91/100."

— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology

Jeju Island Weather History (2010–2024)

Temperature History

Loading chart...

Hall of Fame

Records from last 10 years

Hottest
2018
20.9°C
Coldest
2021
8.7°C
Rainiest
2024
16.8mm

Better Alternatives Nearby

Consider these dates within ±7 days

💡 Moving your event by a few days could significantly improve weather conditions

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Same date (April 20) in other destinations

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📍 Is Jeju Island Worth Visiting on April 20?

Planning a trip to Jeju Island on April 20? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 17.9°C with a 27% historical precipitation risk.

✈️ Travel Logistics: Approximately 165 landing slots available daily during this period, indicating manageable crowd levels.

💉 Health Advisory: 10 vaccinations are recommended for South Korea, including COVID-19.

🌊 Coastal Conditions: Water temperature averages 15.9°C (polar plunge). Wave conditions are generally fun waves with heights around 0.74m.

📊 Historical Extremes: The hottest April 20 recorded in the last 30 years saw temperatures hit 20.9°C in 2018, while the coldest dropped to 8.7°C in 2021.

Jeju Island Weather FAQ