Hilo
Hawaii, USA
Long-term weather forecast
Long-term weather forecast

April weather forecast and climate
Hilo, HI

April, the same as March, is another warm spring month in Hilo, Hawaii, with average temperature ranging between max 79°F (26.1°C) and min 65.5°F (18.6°C).

Temperature

In Hilo, Hawaii, the average high-temperature in April remains equal as in March - a still warm 79°F (26.1°C). In April, the average low-temperature is 65.5°F (18.6°C).

Humidity

The average relative humidity in April is 80.2%.

Rainfall

In Hilo, Hawaii, in April, during 24.9 rainfall days, 10" (255mm) of precipitation is typically accumulated. Throughout the year, there are 272.1 rainfall days, and 84.4" (2144mm) of precipitation is accumulated.

Ocean temperature

In Hilo, in April, the average water temperature is 76.3°F (24.6°C). Depending on a person's sensitivity to cold, with regards to sunshine, wind, and air temperature, a quick swim in 76.3°F (24.6°C) water may be enjoyable. (FYI: The official water temperature required for the Olympic swimming competition is 77°F (25°C) to 82.4°F (28°C).)

Daylight

In Hilo, Hawaii, the average length of the day is 12.6h.

Sunshine

In April, the average sunshine is 4.5h.

UV index

March through September, with an average maximum UV index of 12, are months with the highest UV index in Hilo, Hawaii. A UV Index reading of 11, and higher, represents an extreme threat to health from the exposure to the Sun's UV radiation for the ordinary person.
In April, the average maximum UV index of 12 translate into the following recommendations:
Practice all-important precautions. Light skin people may get burned in less than 5 minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. A broad-spectrum sunscreen of SPF 30+ should be liberally applied and re-applied every two hours, and immediately after an outdoor workout or a swim. Caution! The reflection of sand and water significantly increases the intensity of the Sun's UV radiation.

What is the temperature in April in Hilo?

In Hilo, Hawaii, in April, the average high-temperature is 79°F (26.1°C), and the average low-temperature is 65.5°F (18.6°C).

What is the average humidity in April in Hilo?

The average relative humidity in April is 80.2%.

How much does it rain in Hilo in April?

In Hilo, in April, it is raining for 24.9 days, with typically 10" (255mm) of accumulated precipitation.

What is the water temperature in April in Hilo?

In April, the average ocean temperature in Hilo, Hawaii, is 76.3°F (24.6°C). A person's cold intolerance, with sunshine, wind, and air temperature, are essential factors for enjoying swimming in 76.3°F (24.6°C) water.

What is the average length of the day in April in Hilo?

In Hilo, the average length of the day in April is 12.6h.

How long on average sun shines in April in Hilo?

In Hilo, Hawaii, the average sunshine in April is 4.5h.

What is the month with the highest UV index in Hilo?

March through September, with an average maximum UV index of 12, are months with the highest UV index.

How high is the UV index in April in Hilo?

In Hilo, the average daily maximum UV index in April is 12. A UV Index value of 11, and more, symbolizes an ultimate hazard to health from the exposure to the Sun's UV rays.
Average temperature in April - Hilo, HI
  • Average high temperature in April: 78.9°F

The warmest month (with the highest average high temperature) is September (83.3°F).
The month with the lowest average high temperature is February (78.8°F).

  • Average low temperature in April: 65.5°F

The month with the highest average low temperature is September (69.7°F).
The coldest month (with the lowest average low temperature) is February (63.5°F).

Average humidity in April - Hilo, HI
  • Average humidity in April: 80.2%

The month with the highest relative humidity is November (80.3%).
The month with the lowest relative humidity is February (76%).

Average rainfall in April - Hilo, HI
  • Average rainfall in April: 10"

The wettest month (with the highest rainfall) is March (10.6").
The driest month (with the lowest rainfall) is June (4.3").

Average rainfall days in April - Hilo, HI
  • Average rainfall days in April: 24.9 days

Months with the highest number of rainy days are July and August (26.8 days).
The month with the lowest number of rainy days is February (15.8 days).

Average sea temperature in April - Hilo, HI
  • Average sea temperature in April: 76.3°F

The best month for swimming (with the highest average sea temperature) is September (79.3°F).
The coldest month (with the lowest average sea temperature) is March (75.7°F).

Average daylight in April / Average sunshine in April - Hilo, HI
  • Average daylight in April: 12.6h

The month with the longest days is June (Average daylight: 13.3h).
The month with shortest days is December (Average daylight: 11h).

  • Average sunshine in April: 4.5h

The month with most sunshine is June (Average sunshine: 5.9h).
The month with least sunshine is November (Average sunshine: 3.8h).

Average UV index in April - Hilo, HI
  • Average UV index in April: 12

Months with the highest UV index are March, April, May, June, July, August and September (UV index 12).
The month with the lowest UV index is December (UV index 7).