May weather forecast
Heraklion, Greece

May brings a pronounced increase in both daylight hours and heat, demonstrating a true spring atmosphere. Sunshine duration extends to 9.7 hours, and combined with a sea temperature of 19.5°C (67.1°F), it makes for an ideal climate for outdoor activities. Compared to April, rainfall reduces drastically, making cloudy days an anomaly. As Heraklion shifts closer to its peak summer conditions, anticipate a significant rise in temperatures by June. Despite these changes, sun protection remains imperative, as May showcases a higher UV index.

Temperature

The onset of May marks a slight increase in the average high-temperature, moving from an agreeable 20.2°C (68.4°F) in April to a warm 23.5°C (74.3°F). Heraklion, during the month of May, experiences an average low-temperature of 15.9°C (60.6°F).

Rainfall

In Heraklion, in May, during 1.9 rainfall days, 15mm (0.59") of precipitation is typically accumulated. In Heraklion, during the entire year, the rain falls for 53.2 days and collects up to 501mm (19.72") of precipitation.

Sea temperature

In Heraklion, in May, the average water temperature is 19.5°C (67.1°F).
Note: Most people find it challenging to enjoy swimming in water that is 19.5°C (67.1°F). As water temperature falls below 21°C (69.8°F), controlling breathing grows increasingly difficult.

Daylight

In May, the average length of the day is 14h and 2min.
On the first day of the month, sunrise is at 06:27 and sunset at 20:05. On the last day of May, sunrise is at 06:05 and sunset at 20:28 EEST.

Sunshine

In Heraklion, the average sunshine in May is 9.7h.

UV index

In Heraklion, the average daily maximum UV index in May is 9. A UV Index reading of 8 to 10 represents a very high health vulnerability from unsafe exposure to UV radiation for the average person.
Note: An average UV index of 9 in May transforms into this advice:
Don't neglect protection; skin and eyes can be burned swiftly if left exposed. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.