Last updated: February 24, 2025
Experience the enchanting weather of Honolulu in September, where the tropical warmth invites you to bask in the sunshine. With maximum temperatures reaching 28°C (83°F) and a pleasant average of 26°C (79°F), it's the perfect time to explore the island's stunning landscapes. Evenings cool down to a comfortable minimum of 23°C (75°F), creating an ideal ambiance for relaxation. Expect a modest 19 mm (0.7 in) of rain spread across just four days, allowing for ample opportunities to enjoy outdoor activities. Coupled with a humidity level of 82%, September brings a refreshing mix of sun and occasional showers—making it a delightful month to experience the beauty of Honolulu.
In September, Honolulu greets visitors with mild temperatures, showcasing a transition from the summer heat into a more temperate autumn. With minimums around 23°C (75°F) and averaging at 26°C (79°F), the city maintains its tropical charm while offering a bit of relief from the hotter months. Daytime highs reach 28°C (83°F), indicating that plenty of sunshine is still on offer, perfect for beach outings and outdoor adventures. As the month progresses, temperatures remain stable, reflecting a consistent warmth that characterizes Honolulu's climate throughout the year, making it an inviting destination for those seeking both relaxation and exploration.
September in Honolulu marks a transitional phase in precipitation patterns, with 19 mm (0.7 in) of rain over 4 days. This month experiences a slight uptick in rainfall compared to the drier summer months of July and August, which recorded just 13 mm and 15 mm, respectively. As the season shifts towards fall, the moisture begins to accumulate, hinting at the wetter conditions that will prevail in the coming months. Notably, September’s precipitation amounts serve as a gentle precursor to October, which sees a more significant increase to 45 mm. Overall, while September remains relatively dry compared to the wetter winter months, its rainfall sets the stage for the refreshing changes that autumn brings to the picturesque Hawaiian landscape.
In September, Honolulu experiences a humidity level of 82%, maintaining a trend seen throughout the summer months. This slight dip from the peak of 83% in both July and August suggests a subtle transition into the fall season. Overall, the humidity in Honolulu remains relatively high year-round, with January starting at 78% and only dipping as low as 79% in December. The consistent humidity levels underscore the tropical climate of the region, making it both an inviting and sometimes sticky destination for visitors. As the months progress towards October, the humidity begins to ease, hinting at the changes autumn will bring while still embracing the warm tropical atmosphere.
In Honolulu, the UV Index in September hovers at a significant 12, indicating an extreme exposure category where just 10 minutes of unprotected sun exposure can lead to burning. This trend of high UV levels is consistent with the preceding months, where the index peaked at 13 during the summer, reflecting the region's tropical climate. As autumn approaches, the UV Index begins to taper slightly, yet it remains imperative for sun safety. Throughout the year, particularly from March to September, the UV Index frequently reaches extreme levels, urging residents and visitors alike to embrace protective measures. For further details, check out the complete insights at Honolulu UV Index.
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In September, Honolulu continues to bask in ample sunshine, enjoying 319 hours of glorious sunlight. This marks a slight decrease from the peak summer months of July and August, where the island experienced 350 and 339 hours respectively. However, September still stands out for its vibrant weather, making it the perfect transition month into autumn. As the island gradually shifts toward shorter days, the sunshine experienced in September remains significantly higher than the winter months, which average around 275 hours in November and 260 hours in December. This enduring warmth and brightness exemplify Hawaii's charm, inviting locals and tourists alike to revel in its picturesque landscape before the sun begins its softer autumn descent.
In September, Honolulu enjoys a promising likelihood of sunny weather, with a 70% chance of sun gracing the island. This follows a trend of increasing sunshine as summer transitions into fall, peaking in August at 74%. As the year progresses, the chance of sunny days slightly dips in October but remains robust compared to earlier months, providing a vibrant blend of warm temperatures and clear skies. Overall, September is an excellent time to soak up the sun in this tropical paradise, continuing the trend of generally favorable weather that characterizes late summer and early fall.
In Honolulu, the daylight duration begins its gradual decline as September sets in, stabilizing at around 12 hours of sunshine each day. Following the summer months, which peak with a consistent 13 hours in June, July, and August, the transition into fall sees a slight reduction. This rebalance in daylight mirrors nature’s rhythm as the days slowly shorten, hinting at the approach of winter. As the year unfolds, daylight continues to dwindle, dipping to 11 hours in both October and November, before retreating to 10 hours in the heart of winter. This gentle ebb and flow in sunlight is a testament to Honolulu’s tropical charm, offering abundant daylight for both residents and visitors to enjoy throughout the year.
In September, Honolulu experiences a gentle uptick in wind speeds, averaging 7.7 m/s (17 mph), making it a refreshing month for both locals and visitors. This slight increase follows a summer peak in July at 8.7 m/s (19 mph) and hints at the upcoming autumn shift as October averages climb to 8.0 m/s (18 mph). Interestingly, while September's winds are more invigorating than those in the preceding summer months, they're slightly softer than the more turbulent July air. As the year progresses, we see a clear downward trend in wind speed leading into November, where it dips dramatically to 5.1 m/s (11 mph). This seasonal transition showcases the unique climatic dance of Honolulu, where warm breezes invite adventure before the calmer days of late fall set in.
The weather in Honolulu 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 Honolulu and find detailed weather information for every month.
In September, the weather in Honolulu is warm and humid, with average temperatures reaching around 26°C (79°F), and highs peaking at 28°C (83°F). This month experiences an average of 19 mm (0.7 in) of precipitation over four days, contributing to a humidity level of 82%. In contrast, January sees slightly cooler temperatures, with an average of 23°C (74°F) and maximums reaching 25°C (78°F). Precipitation in January is slightly lower at 16 mm (0.6 in) over the same number of days, and the humidity is a bit reduced at 78%. For a detailed look at January weather, check out Honolulu weather in January.
In comparing the weather between September and February, September tends to be warmer and relatively drier. With minimum temperatures averaging around 23°C (75°F) and maximum temperatures reaching up to 28°C (83°F), September experiences a more consistent warmth throughout the month. In contrast, February's temperatures are cooler, with an average of 23°C (73°F), peaking at 25°C (77°F). Additionally, February sees more rainfall, with 60 mm (2.4 in) over 9 days, compared to just 19 mm (0.7 in) in September across 4 days. Humidity levels remain relatively similar, with September at 82% and February slightly lower at 79%. For a more detailed look at February weather, you can explore Honolulu weather in February.
September and March exhibit notable differences in weather patterns. In September, temperatures are generally warmer, with minimums around 23°C (75°F) and maximums reaching up to 28°C (83°F). The month has relatively low precipitation at 19 mm (0.7 in), occurring over about 4 days, along with a humidity level of 82%. Conversely, March features cooler temperatures overall, with minimums of 19°C (67°F) and maximums of 25°C (77°F). It also experiences significantly higher rainfall, totaling 66 mm (2.6 in) over approximately 9 days, while humidity slightly decreases to 78%. For more detailed insights, check out Honolulu weather in March.
When comparing the weather in September and April, September tends to be slightly warmer, with average temperatures around 26°C (79°F) and maximums reaching 28°C (83°F), while April averages at 24°C (75°F) with a maximum of 25°C (78°F). In terms of precipitation, April is relatively wetter, receiving about 30 mm (1.2 in) over six days, compared to September's 19 mm (0.7 in) over four days. Humidity is quite similar in both months, with September at 82% and April at 81%. For more detailed insights, you can check the link: Honolulu weather in April.
In September, the weather in Honolulu tends to be quite warm, with minimum temperatures around 23°C (75°F) and maximums reaching up to 28°C (83°F). The average temperature hovers around 26°C (79°F), accompanied by relatively low precipitation of 19 mm (0.7 in) over just four days, while humidity remains high at 82%.
In contrast, May experiences slightly cooler temperatures, with a minimum of 19°C (66°F) and a maximum of 27°C (80°F), resulting in an average temperature of 24°C (76°F). However, May sees a bit more rainfall, with precipitation totaling 23 mm (0.9 in) over the same number of rainy days, yet maintaining the same humidity level of 82%. For more detailed information, you can check out Honolulu weather in May.
In comparing the weather of September and June, both months exhibit similar temperature ranges and high humidity levels, maintaining a minimum temperature of around 23°C (75°F) and an average of approximately 26°C (79°F). September experiences slightly warmer maximum temperatures, peaking at 28°C (83°F), compared to June's maximum of 27°C (81°F). However, June tends to have higher precipitation, averaging 27 mm (1.1 in) over 3 days, while September sees only 19 mm (0.7 in) over 4 days. This makes September generally drier despite its marginally warmer temperatures. For more details on June weather, you can check Honolulu weather in June.
In comparing the weather between September and July, we notice that the temperature patterns remain quite similar, with both months featuring a minimum of around 23°C (75°F), an average of 26°C (79°F), and a maximum reaching 28°C (83°F). However, September experiences slightly more precipitation, with 19 mm (0.7 in) spread over 4 days, compared to July's 13 mm (0.5 in) over just 2 days. Humidity levels are also comparable, with September at 82% and July at 83%. Overall, while both months are warm and pleasant, September tends to be wetter and a bit cloudier. For a more detailed overview, you can check Honolulu weather in July.
In comparing the weather between August and September, both months experience similar average temperatures, with September slightly cooler in the mornings, averaging a minimum of 23°C (75°F) compared to August's 24°C (76°F). Humidity levels are also quite comparable, although August is marginally higher at 83% versus September's 82%. Precipitation increases slightly in September, totaling 19 mm (0.7 inches) over four days, while August sees less rain at 15 mm (0.6 inches) over just two days. For more detailed information about August weather, you can explore Honolulu weather in August.
In comparing the weather between September and October, both months exhibit similar average temperatures, with minima at 23°C (75°F) and maxima reaching 28°C (83°F). However, October experiences significantly more precipitation, with 45 mm (1.8 in) over 7 days, compared to September's 19 mm (0.7 in) over just 4 days. The humidity remains relatively constant, at 82% in September and slightly lower at 81% in October. For more detailed information about the weather conditions in October, you can check out Honolulu weather in October.
In September, the weather tends to be warm and slightly more humid, with temperatures ranging from a minimum of 23°C (75°F) to a maximum of 28°C (83°F), and an average of 26°C (79°F). The month sees about 19 mm (0.7 in) of precipitation over approximately four days. In comparison, November experiences slightly cooler temperatures, with a minimum of 21°C (70°F) and a maximum of 27°C (82°F), averaging at 25°C (77°F). However, it also witnesses an increase in precipitation to 25 mm (1.0 in) over six days, while maintaining a similar humidity level of 80%. For more detailed information, you can visit Honolulu weather in November.
In September, the weather tends to be warmer, with average temperatures hovering around 26°C (79°F) and a maximum of 28°C (83°F). The month experiences relatively low precipitation with only about 19 mm (0.7 in) over roughly four days, maintaining a high humidity level of 82%. In contrast, December brings slightly cooler temperatures, with an average of 24°C (75°F) and a maximum of 26°C (79°F), but features significantly more rainfall, totaling 63 mm (2.5 in) over about eight days. Humidity also decreases slightly to 79%. For a detailed overview of the conditions in December, you can visit Honolulu weather in December.
As September rolls into Honolulu, the weather remains pleasantly warm, with a mild average temperature that invites both locals and visitors to enjoy the great outdoors. Unlike the peak summer months, this transitional period sees a slight dip in temperatures, making it an ideal time for beach activities without the intense heat. The humidity remains notable, but with only a handful of rainy days, the likelihood of soaking storms is minimal, allowing for plenty of sunshine. If you're planning a trip, you'll find that the September climate offers a perfect balance—just enough heat to bask in and refreshing breezes to keep you comfortable. For more insights into the overall weather patterns, check out Honolulu Climate.