May weather forecast
Jeju, South Korea

May in Jeju witnesses a marked advancement of spring, turning into early summer with highs around 21.6°C (70.9°F). The month signifies a warmth that permeates not just the weather but also the island's vibrant life. Sights of emerald-green tea fields and lush vegetation dominate, symbolizing the island in full bloom. May showers are scattered but add an overall pleasing appeal making the landscapes more photogenic. With daylight stretching longer and consistent sunshine, May emerges as a preferred month for picnics, sunbathing on the beach, or indulging in water sports.

Temperature

May's arrival is noted with a slight increase in the average high-temperature, moving from an enjoyable 17.5°C (63.5°F) in April to a pleasant 21.6°C (70.9°F). During May, Jeju records a consistent average nighttime temperature of 14.4°C (57.9°F).

Humidity

The average relative humidity in May is 70.4%.

Rainfall

In May, the rain falls for 10.4 days. Throughout May, 96mm (3.78") of precipitation is accumulated. Throughout the year, there are 130.2 rainfall days, and 1498mm (58.98") of precipitation is accumulated.

Sea temperature

In Jeju, the average seawater temperature in May is 16.8°C (62.2°F).
Note: When the surface water temperature is 16.8°C (62.2°F), most do not enjoy swimming. Breathing control becomes more complex as temperatures drop below 21°C (69.8°F).

Daylight

In May, the average length of the day is 13h and 53min.
On the first day of May, sunrise is at 05:45 and sunset at 19:16. On the last day of the month, sunrise is at 05:25 and sunset at 19:38 KST.

Sunshine

The month with the most sunshine in Jeju is May, with an average of 6.8h of sunshine.

UV index

In May, the average daily maximum UV index is 9. A UV Index estimate of 8 to 10 represents a very high health vulnerability from unsafe exposure to UV radiation for average individuals.
Note: The UV index of 9 during May translates into the following guidance:
Always stay safe. Unprotected skin and eyes can get damaged rapidly. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance.