September Weather in Kahalu'u, United States

Last updated: February 24, 2025

In Kahalu'u, September offers a pleasant tropical climate, with average temperatures hovering around 26°C (79°F). Daily highs can reach a comfortable 29°C (85°F), while the mercury rarely dips below 22°C (72°F). This month experiences moderate humidity, averaging 82%, contributing to a lush environment. Rainfall is a common feature, with 37 mm (1.5 in) spread over approximately 12 days, providing refreshing showers that enhance the region's natural beauty. Whether you're soaking up the sun or enjoying the occasional rain, September in Kahalu'u is a delightful blend of warm temperatures and vibrant vegetation.

September Temperature in Kahalu'u

September in Kahalu'u, United States, offers a delightful transition into the mild fall weather, characterized by warm temperatures that linger from summer. With average lows around 22°C (72°F) and highs soaring up to 29°C (85°F), this month reflects a consistent warmth similar to August, though it slightly cools as autumn approaches. The average temperature peaks at 26°C (79°F), making it an ideal time for outdoor activities, beach outings, and enjoying the scenic coastal beauty. As the month progresses, the temperatures begin to trend downwards, hinting at the cooler months ahead, yet for now, September remains a blissful embrace of late summer warmth.

September Weather in Kahalu'u: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Kahalu'u, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec737272747577787979787674
Data source: Temperature data for Kahalu'u generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Kahalu'u

September in Kahalu'u sees a moderate precipitation level of 37 mm (1.5 in), making it one of the drier months of the year. With 12 days of rainfall, the total is lower than the preceding months of March and February, which historically experience higher precipitation. This pattern suggests a gradual transition into the drier autumn season, following the wetter summer months marked by July and August. As the year progresses, Kahalu'u typically witnesses a spike in precipitation again in October, highlighting the dynamic weather patterns that characterize this region throughout the year. The decreasing trend in rainfall during September compared to the summer months sets the stage for the upcoming shifts in weather typical of the fall.

September Precipitation Trends in Kahalu'u

The chart displays monthly precipitation patterns in Kahalu'u, with values for each month alongside September's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec348289514456394137664987
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Kahalu'u

September in Kahalu'u, United States, showcases a slight dip in humidity, settling at 82%—a figure that mirrors the higher humidity levels of the late summer months. As the year progresses from January to August, humidity steadily climbs from 78% to a peak of 83% in July and August, reflecting the tropics' warm embrace. However, as autumn approaches, September marks a subtle transition as humidity begins to ease, paving the way for a gradual decline in the subsequent months. This trend suggests that while Kahalu'u enjoys a humid summer, early fall brings a refreshing shift, hinting at the cooler, more comfortable seasons ahead.

September Average Humidity in Kahalu'u

This chart illustrates the average monthly humidity levels in Kahalu'u, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec78%79%78%81%82%82%83%83%82%81%80%79%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Kahalu'u

In September, Kahalu'u experiences a UV Index of 12, indicating an extreme level of sun exposure that demands caution. With a burn time of just 10 minutes, it’s crucial for sun lovers to be vigilant about protection during outdoor activities. This trend of high UV indexes continues from the previous months, marking summer's peak influence, characterized by extreme readings from June through August. As we transition into fall, September maintains the intensity before slowly tapering off in the following months. For more details on this sun exposure trend and safety tips, check the comprehensive guide at Kahalu'u UV Index.

Maximum UV Index Levels in Kahalu'u for September

The chart shows the monthly maximum UV Index (UVI) for Kahalu'u in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec710111212131313121187
Data source: Kahalu'u September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Kahalu'u

September in Kahalu'u, United States, serves as a glorious transition from the peak summer months, boasting an impressive 319 hours of sunshine. This delightful count reflects a gentle decline following July's record high of 349 hours, yet it remains significantly bright compared to the earlier months of the year. As the days grow shorter, the sun still shines generously, making September an ideal time for outdoor activities and basking in the warm rays. This month marks the tail end of peak sunshine, setting the stage for a cozy autumn, as average sunlight begins to taper off through October and into November. With its idyllic weather, September embodies the perfect blend of lingering summer warmth and the onset of fall's charm.

Monthly Sunshine Duration in Kahalu'u: September Highlighted

The September sunshine duration represents the total number of hours Kahalu'u experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec219h249h286h309h335h338h349h338h319h301h272h255h
Data source: Kahalu'u September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Kahalu'u During September

In Kahalu'u, September enjoys a 59% chance of sunny weather, reflecting a delightful continuation of the warmer months. As summer transitions into fall, the likelihood of sunshine remains relatively high, closely mirroring August's impressive 63%. This trend highlights the region's propensity for pleasant weather, particularly from late spring through early fall, with May peaking at 64%. While the chances slightly dip in the cooler months, September still demonstrates a favorable outlook for outdoor activities, making it an enticing time for visitors and locals alike to soak up the sun.

Percentage of Sunny Days in September in Kahalu'u

The chart illustrates the percentage of sunny days in Kahalu'u throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Kahalu'u experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec52%59%46%54%64%61%48%64%59%62%57%36%
Data source: Kahalu'u September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Kahalu'u in September

As summer transitions into autumn, September in Kahalu'u offers a delightful balance of daylight, providing residents with approximately 12 hours of sunshine. This continuity from the previous months reflects a gradual tapering of daylight that began in August, where the hours decreased from the peak summer days. Notably, September maintains this gentle equilibrium as it aligns with April and March, both having 12 hours of daylight as well. The shift heralds the impending shorter days of fall, with October and November poised to offer just 11 hours of daylight as the year wraps up. Overall, this month serves as a bridge, allowing the community to savor the lingering warmth and brightness before the days start to dwindle more significantly.

Average Daylight Hours in Kahalu'u for September

The chart illustrates the variation in daylight duration in Kahalu'u throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 59m11h 26m12h 2m12h 38m13h 9m13h 24m13h 15m12h 48m12h 13m11h 36m11h 5m10h 50m
Data source: Kahalu'u daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Kahalu'u

In Kahalu'u, United States, the weather in September brings a refreshing wind that echoes the transitional spirit of early autumn. With an average wind speed of 6.1 m/s (14 mph), this month matches the gusty conditions of January, suggesting a return to brisk breezes as the summer heat subsides. Interestingly, September marks a shift from the lower winds typical of April and November, while also being close to the stronger July winds at 7.0 m/s (16 mph). This trend underscores a harmonious blend of summer’s lingering warmth with the invigorating touch of fall, making September a delightful time for outdoor activities, infused with nature's lively whispers.

Average September Wind Speed in Kahalu'u

The chart displays monthly wind speed patterns in Kahalu'u, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec6.15.75.95.05.75.57.05.96.1 m/s6.24.16.2
Data source: Kahalu'u September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Kahalu'u Compares to Other Months

The weather in Kahalu'u 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 Kahalu'u and find detailed weather information for every month.

In comparing the weather of September and January, September tends to be slightly warmer with average temperatures around 26°C (79°F), peaking at a maximum of 29°C (85°F), while January's averages are cooler at 23°C (73°F) with a maximum of 27°C (80°F). Both months experience a similar level of precipitation, with September averaging 37 mm (1.5 in) over 12 days and January slightly less at 34 mm (1.3 in) over 9 days. Humidity levels are also comparable, with September at 82% and January at 78%, making both months feel relatively comfortable but still on the humid side. For more detailed insights, you can check Kahalu'u weather in January.

September generally boasts warmer temperatures, with averages around 26°C (79°F) and highs reaching 29°C (85°F). In contrast, February tends to be milder, with an average temperature of 22°C (72°F) and maximums of 26°C (79°F). Precipitation levels are also noteworthy; September experiences 37 mm (1.5 in) of rain over 12 days, while February sees a significantly higher rainfall of 82 mm (3.2 in) across 14 days. Humidity levels are relatively similar, with September at 82% and February slightly lower at 79%. For more detailed insights about the weather conditions in February, you can check Kahalu'u weather in February.

In comparing the weather between September and March, September is characterized by warmer temperatures, with a minimum of 22°C (72°F) and an average of 26°C (79°F), compared to March's minimum of 19°C (66°F) and an average of 22°C (73°F). September also experiences less precipitation, accumulating 37 mm (1.5 in) over 12 days, while March sees significantly more rainfall with 89 mm (3.5 in) over 16 days. Humidity levels are slightly higher in September at 82%, compared to 78% in March. For more details on March weather conditions, you can visit Kahalu'u weather in March.

In September, the weather is typically warmer, with average temperatures ranging from a minimum of 22°C (72°F) to a maximum of 29°C (85°F), while April sees slightly cooler temperatures with a minimum of 19°C (66°F) and a maximum of 27°C (80°F). Both months experience a fair amount of rainfall, but April has higher precipitation at 51 mm (2.0 in) over 13 days compared to September's 37 mm (1.5 in) over 12 days. Interestingly, the humidity levels are relatively similar, with September sitting at 82% and April at 81%. For more detailed insights on the weather specifics, you can check Kahalu'u weather in April.

In comparing the weather between September and May, we find that September tends to be slightly warmer, with average temperatures of 26°C (79°F) compared to May's 24°C (75°F). Both months experience high humidity levels, remaining consistently around 82%. However, September has slightly less precipitation, recording 37 mm (1.5 in) over 12 days, whereas May sees 44 mm (1.7 in) across 13 days. For a more detailed look at May weather specifically, you can check out Kahalu'u weather in May.

In comparing the weather of September and June, both months exhibit warm temperatures and high humidity, with September slightly warmer on average. September's temperature ranges from a minimum of 22°C (72°F) to a maximum of 29°C (85°F), with an average of 26°C (79°F). In contrast, June's temperatures are a bit cooler, with a minimum of 22°C (72°F), an average of 25°C (77°F), and a maximum of 28°C (83°F). Additionally, June sees higher precipitation levels totaling 56 mm (2.2 in) over 11 days, compared to September’s 37 mm (1.5 in) across 12 days. Both months maintain a consistent humidity level of 82%. For a closer look at June's weather in a specific area, check out Kahalu'u weather in June.

In comparing the weather between September and July, both months exhibit similar temperature ranges, with September showcasing a minimum of 22°C (72°F), an average of 26°C (79°F), and a maximum of 29°C (85°F). July, on the other hand, has a slightly lower maximum of 28°C (83°F) while maintaining the same minimum and average temperatures. Precipitation levels are quite close, with September receiving 37 mm (1.5 in) over 12 days and July experiencing a bit more rain at 39 mm (1.5 in) spread across 16 days. Humidity remains relatively high in both months, with September at 82% and July slightly higher at 83%. For more details about the weather in July, you can visit Kahalu'u weather in July.

In comparing the weather of September and August, we see that both months exhibit similar average temperatures, with September having a minimum of 22°C (72°F) compared to August's 23°C (73°F). Both months also share an average temperature of 26°C (79°F) and a maximum of 29°C (85°F). However, September experiences slightly less precipitation, with 37 mm (1.5 in) over 12 days, while August sees a bit more with 41 mm (1.6 in) across the same number of days. Humidity levels remain comparable, with September at 82% and August slightly higher at 83%. For a more detailed look at August's weather, you can check this link: Kahalu'u weather in August.

In comparing the weather between September and October, September boasts slightly warmer temperatures, with an average of 26°C (79°F) compared to October's 25°C (78°F). Both months have a minimum of 22°C (72°F) and reach similar maximums of 29°C (84°F in October and 85°F in September). However, October experiences more precipitation, with a total of 66 mm (2.6 in) over 15 days, compared to September's 37 mm (1.5 in) over 12 days. Additionally, humidity levels remain fairly consistent, with September at 82% and October slightly lower at 81%. For more details on the weather in October, you can visit Kahalu'u weather in October.

In September, the weather features slightly warmer temperatures, with an average of 26°C (79°F), while minimum temperatures hover around 22°C (72°F) and maximums reach up to 29°C (85°F). The month sees a moderate amount of rainfall, with 37 mm (1.5 in) over approximately 12 days and humidity levels around 82%.

Contrastingly, November experiences slightly cooler conditions, averaging 25°C (76°F) with minimums of 20°C (69°F) and maximums remaining consistent at 29°C (84°F). However, it also receives more rainfall, totaling 48 mm (1.9 in) distributed over 16 days, and keeps humidity at a comparable level of 80%. For more insights, check out Kahalu'u weather in November.

In September, the weather tends to be warmer, with average temperatures reaching around 26°C (79°F) and maximums peaking at 29°C (85°F). The month experiences a fair amount of precipitation, totaling 37 mm (1.5 in) over about 12 days, combined with humidity levels at 82%. In contrast, December sees cooler temperatures, with averages dropping to 23°C (74°F) and maximums at 27°C (81°F). However, it is wetter, receiving 87 mm (3.4 in) of rain over 16 days, and slightly lower humidity at 79%. For more details about December weather, you can visit Kahalu'u weather in December.

Compare Kahalu'u's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Kahalu'u

As September settles over Kahalu'u, the weather begins to transition, marked by a notable balance between warmth and humidity. With maximum temperatures reaching a comfortable 29°C (85°F) and an average hovering around 26°C (79°F), the pleasant warmth invites outdoor activities while the humidity often lingers at 82%, creating a tropical ambiance. Although September sees increased precipitation with rain on about 12 days, the overall amount remains manageable, allowing for ample sunny intervals. This combination of warmth and moisture differentiates September from the drier summer months, paving the way for a lush landscape. For a broader understanding of this tropical haven, explore the Kahalu'u Climate.