Last updated: February 24, 2025
Experience the charm of Ko Olina, United States, in September, where the weather offers a delightful blend of warmth and occasional rain. With maximum temperatures reaching 28°C (83°F) and an average of 26°C (80°F), visitors can enjoy pleasant beach days and outdoor activities. The minimum temperature dips to a comfortable 24°C (76°F) at night, perfect for unwinding after a sun-soaked day. Precipitation is light, with only 13 mm (0.5 in) expected over just 2 days, and humidity averages around a tropical 82%, adding to the lush beauty of the region. Whether you're lounging on the beach or exploring local attractions, September in Ko Olina promises a refreshing escape.
In September, Ko Olina embraces the peak of warmth, with temperatures steadily holding at a minimum of 24°C (76°F) and reaching an average of 26°C (80°F), peaking at 28°C (83°F). This month mirrors the conditions of August, suggesting a consistent, inviting climate ideal for beach activities and outdoor adventures. As summer transitions to fall, the gentle, tropical breezes continue to keep the atmosphere pleasant, while evening temperatures remain comfortably warm. Overall, September delivers an ideal setting for travelers seeking sun and relaxation in this picturesque Hawaiian paradise.
September in Ko Olina brings a slight uptick in precipitation, with 13 mm (0.5 in) of rain recorded over 2 days. This period marks a transition from the drier summer months of July and August, where rainfall was minimal—a mere 6 mm and 9 mm, respectively. As the region approaches October, known for a more significant increase in rainfall (up to 42 mm), September sets the stage for the wetter months ahead, indicating a gradual shift in weather patterns. The early fall typically offers a blend of sunny days with occasional light showers, creating a refreshing atmosphere before the more consistent rain arrives.
In September, Ko Olina experiences a humidity level of 82%, which aligns closely with the peaks observed in the summer months of July and August, both at 83%. This slight dip in humidity reflects the gradual transition towards autumn, although the coastal climate remains comfortably humid. Throughout the year, humidity fluctuates moderately, with the lowest levels recorded in January and March at 78%. Interestingly, the data shows a general upward trend from January to August, before stabilizing in the fall, indicating that while Ko Olina enjoys a tropical paradise, the humidity remains a consistent hallmark of its inviting atmosphere.
As summer transitions to fall in Ko Olina, the UV Index remains impressively high in September, holding steady at 12—an indication of extreme exposure. This consistent pattern of elevated UV levels mirrors the trends seen throughout the peak summer months, where the burn time is notably quick at just 10 minutes. With rates in September similar to those of the preceding months, it’s crucial for sun-seekers to take precautions. As you soak in the last of the summer sun, remember to stay protected! For a detailed overview of UV trends year-round, check out Ko Olina UV Index.
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September in Ko Olina shines brightly with 318 hours of sunshine, reflecting the tail end of a summer filled with light. As the year progresses, the trend shows a peak in July with 349 hours, gradually tapering off into the autumn months. The sunny disposition of September subtly bridges the vibrant summer and the slightly cooler fall, ensuring that visitors continue to bask in pleasant weather, enjoying the stunning beaches and outdoor activities. With sunshine hours significantly higher than the winter months, such as November’s 273 hours, Ko Olina remains a sunny escape that charms travelers throughout the year.
In September, Ko Olina basks in abundant sunshine, boasting a 71% chance of clear skies. This places it comfortably among the sunniest months, following a vibrant August with a 74% likelihood of sunshine. As the summer season winds down, the chances of enjoying those warm, sunny days remain high, offering travelers and locals alike the perfect backdrop for outdoor adventures. Notably, the sunny trend continues into October with a slightly lower 70%, making it an ideal time to soak up the beautiful Hawaiian climate before the year draws to a close. Overall, September's weather promises a delightful blend of sunshine and warmth, making it an alluring time to visit.
As we step into September in Ko Olina, daylight graces the island for about 12 hours each day, maintaining the steady illumination observed over the previous months. This transition marks a subtle but important shift, as daylight hours peak during May through August at 13 hours, nurturing the vibrant summer energy. However, September signals the start of a gradual decline, echoing the patterns of October and November, where daylight begins to dwindle again to 11 hours. The consistent framework of daylight in Ko Olina throughout the year offers both locals and visitors a comfortable rhythm, making it an idyllic destination for sun-soaked adventures.
As September unfolds in Ko Olina, the average wind speed hovers around 6.8 m/s (15 mph), creating a delightful atmosphere for outdoor enthusiasts. This month marks a slight increase compared to the calmer summer breezes of June and July, where winds reached 5.9 m/s and 7.8 m/s respectively. Looking at the broader picture, September's winds transition into the gentler patterns of autumn as they dip from the summer peak, but they remain robust enough to provide an invigorating backdrop against the stunning coastal scenery. With wind speeds tending to rise again in October, September strikes a harmonious balance that continues to charm residents and visitors alike.
The weather in Ko Olina changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Ko Olina and find detailed weather information for every month.
In September, the weather is typically warmer, with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 28°C (83°F). The month features greater humidity at 82% and slightly more precipitation, totaling 13 mm (0.5 in) over about 2 days. In contrast, January enjoys slightly cooler temperatures with a minimum of 20°C (69°F) and a maximum of 25°C (78°F), along with a decrease in humidity to 78% and lower precipitation at 10 mm (0.4 in) over the same number of days. For a detailed look at January's conditions, visit Ko Olina weather in January.
In September, the weather is typically warmer, with average temperatures around 26°C (80°F) and a maximum of 28°C (83°F), while February sees cooler conditions, with averages dropping to 23°C (73°F) and a maximum of 25°C (78°F). September experiences relatively low precipitation with only 13 mm (0.5 in) over just 2 days, whereas February is much wetter, recording 58 mm (2.3 in) of rain over 7 days. Despite the differences in temperature and rainfall, both months maintain high humidity levels, with September at 82% and February at 79%. For a more detailed look at February's weather, visit Ko Olina weather in February.
In comparing the weather between September and March, September is generally warmer and drier, with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 28°C (83°F) and only 13 mm of precipitation over about 2 days. In contrast, March experiences cooler temperatures, with a minimum of 19°C (67°F) and a maximum of 25°C (78°F), while also being wetter, receiving 59 mm of rain over 6 days. Additionally, September has higher humidity levels at 82%, compared to March's 78%. For a more detailed look at the weather patterns, check out Ko Olina weather in March.
In comparing the weather between September and April, September tends to be slightly warmer, with average temperatures around 26°C (80°F) and maximums reaching up to 28°C (83°F). In contrast, April's temperatures are a bit cooler, averaging 24°C (75°F) with maximums only hitting 25°C (78°F). Additionally, September experiences less precipitation, at about 13 mm (0.5 in) over approximately 2 days, compared to April's 21 mm (0.8 in) spread over 3 days. Humidity levels are fairly comparable, with September at 82% and April at 81%. For a more detailed look at April's climate, you can check out Ko Olina weather in April.
In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 28°C (83°F), with an average of 26°C (80°F). The month sees about 13 mm (0.5 in) of precipitation over two days, maintaining a consistent humidity level of 82%. In comparison, May offers slightly cooler temperatures, with a minimum of 20°C (68°F), an average of 24°C (76°F), and a maximum of 27°C (80°F). Precipitation in May is slightly higher at 16 mm (0.6 in), but it only occurs on one day, also with 82% humidity. Overall, September tends to be a bit warmer while May brings slightly more rain. For more detailed insights, check out Ko Olina weather in May.
In comparison, September generally showcases slightly warmer temperatures than June, with daily averages of 26°C (80°F) in September versus 25°C (78°F) in June. The maximum temperatures in September reach up to 28°C (83°F), while June peaks at 27°C (81°F). Interestingly, although September has a lower total precipitation at 13 mm (0.5 in) across 2 days, June experiences more rain with 33 mm (1.3 in) but only on 1 day. Both months maintain a consistent humidity level of 82%, contributing to the tropical feel typical of the region. For a more detailed look, you can check the Ko Olina weather in June.
When comparing the weather in September to that of July, we see quite a few similarities. Both months have a minimum temperature of around 24°C (76°F), with average temperatures hovering close to 26°C (80°F) and maximum temperatures reaching up to 28°C (83°F). However, September experiences slightly higher precipitation, with 13 mm (0.5 in) over 2 days, compared to July's 6 mm (0.3 in) over just 1 day. Humidity levels are also comparable, with September at 82% and July at 83%. For more specific insights on July weather, you can refer to Ko Olina weather in July.
In comparing the weather of September and August, we see that both months exhibit similar temperature ranges, with minimums of 24°C (76°F), averages of 26°C (80°F), and maximums of 28°C (83°F). However, September experiences slightly more precipitation, totaling 13 mm (0.5 in) over 2 days, compared to August's 9 mm (0.4 in) during the same number of days. Humidity levels are quite comparable as well, with September at 82% and August marginally higher at 83%. For a closer look at the weather specifics for August, you can check the details here: Ko Olina weather in August.
September typically features warm temperatures with a minimum of 24°C (76°F) and an average of 26°C (80°F), peaking at 28°C (83°F). The month sees limited rainfall, with only 13 mm (0.5 in) of precipitation over just 2 days and an average humidity of 82%. In contrast, October maintains similar temperature ranges, with a minimum of 23°C (73°F), an average of 26°C (79°F), and a maximum of 28°C (83°F). However, October experiences a notable increase in precipitation, totaling 42 mm (1.7 in) over 5 days, while humidity remains slightly lower at 81%. Overall, while the temperatures are consistent, October brings more rain and slightly lower humidity. For more details, you can check Ko Olina weather in October.
In September, the weather tends to be warmer with average temperatures around 26°C (80°F) and maxing out at 28°C (83°F). The month receives relatively little rainfall, with only 13 mm (0.5 in) of precipitation over just 2 days, coupled with a humidity level of 82%. In contrast, November experiences slightly cooler temperatures with an average of 25°C (78°F), a minimum of 21°C (71°F), and a maximum of 27°C (81°F). However, it sees increased precipitation at 18 mm (0.7 in) across 5 days, while maintaining a similar humidity level of 80%. For a detailed look at the conditions during this time, check out Ko Olina weather in November.
In September, the weather is characterized by warmer temperatures, with daily averages around 26°C (80°F) and maximums reaching 28°C (83°F). The month sees minimal precipitation, with only 13 mm (0.5 in) over 2 days, and humidity levels remain high at 82%. In contrast, December features cooler temperatures, with a minimum of 19°C (67°F) and an average of 24°C (76°F), peaking at 26°C (79°F). However, December experiences significantly higher rainfall, totaling 70 mm (2.8 in) over 5 days, and slightly lower humidity at 79%. For those interested in more detailed statistics, visit Ko Olina weather in December.
As September rolls in, Ko Olina experiences a delightful transition in weather that invites visitors to soak up the sun. With temperatures averaging a comfortable 26°C (80°F), it strikes a perfect balance between warmth and mildness. Unlike the hotter summer months, September sees a slight dip in humidity and a welcome reduction in precipitation, typically experiencing just 2 rainy days throughout the month. This makes it an ideal time for outdoor adventures and beach activities. For those interested in understanding the full scope of Ko Olina's climate, be sure to explore Ko Olina Climate for more insights.