May weather forecast
Surabaya, Indonesia

May in Surabaya marks the real advent of the dry season with minimum rainfall recorded at 47mm. Encouragingly, sun lovers will enjoy the steadily increasing sunshine hours. The weather remains warm, but the declining humidity levels create a charmingly comfortable atmosphere. As the wet season's receding show, sea temperatures continue to drop while maintaining ideal swimming and water sport conditions. By the end of the month, residents and visitors can look forward to more sunshine and less rainfall.

Temperature

May's weather in Surabaya, Indonesia, displays an average high-temperature of a still hot 30.8°C, slightly varied from April's 30.5°C. Surabaya usually reports an average low-temperature of 25.7°C during the month of May.

Heat index

For May, the heat index is estimated at a very hot 38°C. Undertake additional precautions, heat cramps and heat exhaustion could happen. Heatstroke could occur from sustained activity.
Research indicates the heat index considers values in shaded locales and with light winds. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is what the temperature feels like to the human body when the air temperature is combined with the relative humidity. The individual's impression of temperature can be affected by numerous factors such as metabolic variations, physical exertion, and attire. Keep in mind that direct sunshine exposure can amplify the weather's effects, possibly increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Children often overlook the necessity for resting and fluid replenishment. Thirst is a late sign of dehydration - thus, it is critical to stay hydrated, especially during extended periods of physical activities.
The human body has a built-in cooling mechanism through perspiration; evaporating sweat dissipates the excess heat. Increased relative humidity interferes with body cooling by slowing the rate of evaporation, resulting in a slower body cooling rate and a heightened feeling of heat. Heat-related complications, like dehydration, can manifest if the body's heat gain exceeds its dissipation capacity.

Humidity

In Surabaya, the average relative humidity in May is 74%.

Rainfall

In Surabaya, in May, it is raining for 14.1 days, with typically 47mm of accumulated precipitation. In Surabaya, Indonesia, during the entire year, the rain falls for 187.8 days and collects up to 839mm of precipitation.

Sea temperature

In Surabaya, the average seawater temperature in May is 29.5°C.
Note: Water temperature between 25°C and 29°C is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

Daylight

In Surabaya, the average length of the day in May is 11h and 47min.
On the first day of May in Surabaya, sunrise is at 05:30 and sunset at 17:21. On the last day of the month, sunrise is at 05:34 and sunset at 17:18 WIB.

Sunshine

In May, the average sunshine in Surabaya is 9.5h.

UV index

January through December, with an average maximum UV index of 7, are months with the highest UV index in Surabaya. The months with the lowest UV index in Surabaya are January through December, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to UV radiation for ordinary individuals.
Note: The maximum UV index, 7 during May, leads to the following recommendations:
Prevent overexposure. Protection from the sun's harmful effects is needed. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Caution! The Sun's UV intensity grows with reflections off sand and water.