May weather forecast
Haikou, China

May reaps the benefits of April’s increased rainfall, leveraging it to display a rich luxuriance of flora across the city. Temperatures aim for a blazing high of 31.9°C (89.4°F), showcasing true summer conditions. Humidity remains high throughout May, moving in tandem with the mounting temperatures, and the city begins its long, wet trek into summer, transitioning from the comparatively dry and mild conditions of April.

Temperature

May's arrival brings an average high-temperature of a hot 31.9°C (89.4°F), demonstrating subtle variation from the preceding month. Haikou, during the month of May, experiences an average low-temperature of 24.5°C (76.1°F).

Heat index

May's average heat index is calculated to be a burning hot 46°C (114.8°F). Stay wary: Heat exhaustion and heat cramps are possible. Heatstroke can ensue from extended effort.
When considering the heat index, it's pivotal to note it is for shade and mild wind conditions. If exposed to direct sunlight, the heat index could climb by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', stands as a testimony to how temperature and humidity combine to impact our sense of warmth. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. Keep aware, the sun, when shining directly, can intensify the heat experience, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
In the face of high temperatures, the human body's reflex is to perspire, leveraging sweat evaporation for cooling. With higher relative humidity, the rate of evaporation is reduced, resulting in increased heat retention in the body compared to drier air. Potential thermal conditions emerge as the body's heat gain outpaces its cooling mechanisms.

Humidity

In Haikou, the average relative humidity in May is 84%.

Rainfall

In Haikou, in May, during 16.5 rainfall days, 181mm (7.13") of precipitation is typically accumulated. Throughout the year, there are 145 rainfall days, and 1652mm (65.04") of precipitation is accumulated.

Sea temperature

In Haikou, China, the average seawater temperature in May is 27.4°C (81.3°F).
Note: For swimming, diving, and enjoying other water activities, the range of 25°C (77°F) to 29°C (84.2°F) in water temperature is considered ideal, offering pleasure for extended periods without discomfort.

Daylight

The average length of the day in May is 13h and 5min.
On the first day of the month, sunrise is at 06:09 and sunset at 19:02. On the last day of May, sunrise is at 05:59 and sunset at 19:14 CST.

Sunshine

The average sunshine in May in Haikou, China, is 7h.

UV index

March through September, with an average maximum UV index of 12, are months with the highest UV index in Haikou. A UV Index estimate of 11, and higher, represents an extreme health hazard from exposure to the Sun's UV rays for the average person.
Note: A maximum high UV index of 12 in May translates into the following recommendations:
Adopt every precaution of necessity, unprotected skin and eyes may suffer burns instantly. Attempt to stay under shade and limit exposure to the Sun between 10 a.m. and 4 p.m., when UV radiation is at its peak. Remember, devices such as parasols or canopies might not provide complete sun protection. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Regularly apply and reapply a broad-spectrum sunscreen with a minimum SPF 30 every two hours, or straight after swimming or an outdoor activity. Be attentive! The UV exposure is heightened with reflections from sand and water.