September weather forecast
Kaneohe, HI

As summer trails off, September in Kaneohe witnesses a subtle dip in average high temperatures to 80.8°F (27.1°C). Aligned with this, the sea temperature reaches a pleasant 80.4°F (26.9°C), the highest recorded all year. Consequently, September triggers the perfect time for beach enthusiasts and water adventurers to plunge into the various oceanic activities. The climate remains appealing for sightseeing, despite a slight increase in rainfall. The harmonious blend of September's weather elements continues to add depth to Kaneohe's enrapturing tropical appeal.

Temperature

Kaneohe's peak temperatures tend to occur in August and September, with an average high-temperature of 81°F (27.2°C).

Heat index

September's mean heat index is calculated to be a tropical 86°F (30°C). If one continues to be active during exposure, it might cause tiredness and subsequent heat cramps.
It is important to note that the heat index values are for shaded areas and light wind scenarios. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', marries air temperature and humidity to produce a value illustrating perceived warmth. Metabolic differences, pregnancy status, and the level of physical activity are additional factors influencing an individual's weather perception. One's exposure to direct sunlight has the potential to intensify the heat sensation, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.

Humidity

January, May, June, September and November, with an average relative humidity of 75%, are the least humid months in Kaneohe.

Rainfall

In Kaneohe, during September, the rain falls for 14.5 days and regularly aggregates up to 1.1" (28mm) of precipitation. In Kaneohe, during the entire year, the rain falls for 187.1 days and collects up to 15.83" (402mm) of precipitation.

Ocean temperature

With an average ocean temperature of 80.4°F (26.9°C), September is the month with the warmest seawater.
Note: Between 77°F (25°C) and 84.2°F (29°C), water temperature is typically considered very warm and pleasurable by everyone. Water activities at these temperatures are enjoyable for extended periods without discomfort.

Daylight

In Kaneohe, the average length of the day in September is 12h and 15min.
On the first day of the month, sunrise is at 6:14 am and sunset at 6:46 pm. On the last day of September, sunrise is at 6:22 am and sunset at 6:19 pm HST.

Sunshine

In September, the average sunshine is 9h.

UV index

July through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to UV radiation for the average person.
Note: The maximum UV index of 7 during September leads to these instructions:
Adhere to precautions and respect sun safety doctrines. Avoiding sunburn is vital. 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. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Warning! Sand and water reflections boost the intensity of UV exposure.