September Weather in Ratnapura, Sri Lanka

Last updated: March 19, 2025

September in Ratnapura, Sri Lanka offers a dynamic blend of subtropical weather conditions. With average temperatures hovering around 23°C (74°F), daily highs can reach up to 29°C (84°F), providing warm and humid days. Minimum temperatures dip to a comfortable 19°C (66°F) at night, creating ideal conditions for evening activities. Expect significant precipitation, with 287 mm (11.3 in) of rain spread across 26 days, making September one of the wetter months. The humidity level remains high at 81%, which, combined with frequent rainfall, enhances the lush, vibrant landscape characteristic of this enchanting region.

September Temperature in Ratnapura

In September, Ratnapura, Sri Lanka experiences a delightful shift in temperatures, characterized by a minimum of 19°C (66°F) and an average that remains steady at 23°C (74°F). The highs tend to reach 29°C (84°F), providing a comfortable warmth ideal for exploring the lush surroundings. This month marks a subtle transition from the cooler, drier conditions of the previous months, with temperatures gradually rising but still maintaining a pleasant climate. Overall, September in Ratnapura offers a balanced warmth, making it an inviting time for both locals and visitors to enjoy the vibrant landscapes.

September Weather in Ratnapura: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Ratnapura, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec737475767675757474747474
Data source: Temperature data for Ratnapura generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Ratnapura

September in Ratnapura, Sri Lanka, sees a significant precipitation of 287 mm (11.3 in), typically spread over 26 days. This month marks a transition as rainfall slightly decreases compared to the preceding months of May through August, with May peaking at 431 mm (17.0 in). As the region shifts toward the intense rains of late fall, September's wet conditions set the stage for the even heavier downpours expected in October and November, where precipitation dramatically increases. The consistent rainfall throughout these months underscores the characteristic tropical climate of Ratnapura, offering both lush landscapes and challenges of wet weather.

September Precipitation Trends in Ratnapura

The chart displays monthly precipitation patterns in Ratnapura, 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.
JanFebMarAprMayJunJulAugSepOctNovDec241289384415431233219245287475643402
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Ratnapura

In September, Ratnapura experiences a notable humidity level of 81%, which aligns closely with the high humidity of the preceding months, particularly August's peak at 85%. This trend indicates that the region remains quite humid as it transitions from the dampness of the mid-year months, such as June and July, both hovering around 81-85%. As the year progresses towards October, humidity levels are expected to rise even further, peaking at 89%, suggesting that Ratnapura is characterized by a tropical climate marked by consistently high humidity, especially during the latter part of the year.

September Average Humidity in Ratnapura

This chart illustrates the average monthly humidity levels in Ratnapura, 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.
JanFebMarAprMayJunJulAugSepOctNovDec80%72%69%69%79%85%81%85%81%89%88%87%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Ratnapura

In September, Ratnapura, Sri Lanka, experiences a UV Index of 14, which falls into the extreme exposure category, highlighting the ongoing need for sun protection. This month showcases a slight dip compared to the peak values seen in March, April, and May, where the index reached 15. Despite this slight decrease, the recommended burn time remains at a swift 10 minutes, reinforcing the importance of vigilance under the sun. Interestingly, the UV Index maintains a relatively high standard through the year, with only minor fluctuations from January's UV index of 12 to the 11 in December. Those enjoying the outdoors in September should stay alert and take precautions to avoid skin damage. For more information on UV levels, visit Ratnapura UV Index.

Maximum UV Index Levels in Ratnapura for September

The chart shows the monthly maximum UV Index (UVI) for Ratnapura 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.
JanFebMarAprMayJunJulAugSepOctNovDec121415151513131414131211
Data source: Ratnapura 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 Ratnapura

September in Ratnapura, Sri Lanka, is graced with 311 hours of sunshine, making it a delightful transition from the vibrant summer months. Following a peak of 336 hours in July, the sun begins to soften in intensity but remains generous compared to the earlier months of the year. This slight decline is a continuation of a trend observed throughout the year, where the sunlight gradually tapers from the high summer peak, yet still delivers ample brightness. The consistent sunshine, notably from April to September, invites both locals and tourists to revel in the enchanting landscapes, lush greenery, and the warm hospitality that Ratnapura is renowned for. As the golden sunlight bathes the hills, it sets a picturesque backdrop for exploration and adventure.

Monthly Sunshine Duration in Ratnapura: September Highlighted

The September sunshine duration represents the total number of hours Ratnapura 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.
JanFebMarAprMayJunJulAugSepOctNovDec268h309h333h331h319h331h336h334h311h303h277h306h
Data source: Ratnapura September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Ratnapura During September

In Ratnapura, Sri Lanka, the likelihood of sunny weather in September is relatively low, sitting at 13%. This trend fits into the broader pattern observed throughout the year, where the months preceding September—particularly July and August—experience even less sunshine, with chances plummeting to 11% and 6% respectively. As the year progresses into the dry season, the odds of sunny days begin to rise significantly, peaking in December at 40%. Thus, while September offers a modest chance for sunshine, it remains part of a wetter period characterized by more overcast days, setting the stage for the brighter months ahead.

Percentage of Sunny Days in September in Ratnapura

The chart illustrates the percentage of sunny days in Ratnapura 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 Ratnapura experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec15%36%26%37%13%18%11%6%13%12%12%41%
Data source: Ratnapura September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Ratnapura in September

In Ratnapura, Sri Lanka, the trend of daylight duration reveals a fascinating consistency throughout the year. From January through August, daylight remains relatively stable at around 11 to 12 hours, fostering a feeling of balance and predictability. As spring rolls in with March, there’s a pleasant increase to a full 12 hours of daylight, which continues unabated until September. This month maintains the generous allotment of 12 hours, offering ample opportunity for exploration and immersion in the lush landscapes surrounding the city. However, as autumn approaches in October, daylight begins to wane again, dropping back to 11 hours. This rhythm of daylight showcases the tropical climate's gentle transitions, reminding residents and visitors alike of the beauty of nature's cycles.

Average Daylight Hours in Ratnapura for September

The chart illustrates the variation in daylight duration in Ratnapura throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 46m11h 53m12h 4m12h 15m12h 24m12h 29m12h 27m12h 18m12h 8m11h 57m11h 48m11h 43m
Data source: Ratnapura daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Ratnapura

In September, Ratnapura experiences a slight dip in wind speed, averaging 2.1 m/s (5 mph), a trend observed during the wet season. This month follows the peak winds of July (2.5 m/s) and a moderate breeze in August, suggesting a gentle transition towards the calmer months ahead. The increasing winds from May to July mark a lively period, while the gradual decrease into the fall mirrors the region's seasonal rhythm. As the winds soften in September, the lush landscapes of Ratnapura remain vibrant, creating a tranquil atmosphere for both locals and visitors to savor the charm of this enchanting Sri Lankan town.

Average September Wind Speed in Ratnapura

The chart displays monthly wind speed patterns in Ratnapura, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.11.11.11.31.92.22.52.22.1 m/s1.71.71.0
Data source: Ratnapura September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Ratnapura Compares to Other Months

The weather in Ratnapura 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 Ratnapura and find detailed weather information for every month.

September and January present a fascinating contrast in weather conditions. September tends to be warmer overall, with average temperatures hovering around 23°C (74°F) and a maximum of 29°C (84°F), while January shows a slightly lower minimum temperature of 15°C (59°F) and maxing out at 30°C (86°F). Despite having fewer rainy days, January still sees significant precipitation at 241 mm (9.5 in), compared to September's 287 mm (11.3 in) over more days. Humidity levels remain relatively consistent, with September at 81% and January at 80%, making both months feel humid yet distinct. For a closer look at January conditions, visit Ratnapura weather in January.

In comparing the weather of September and February, September typically experiences warmer conditions with an average temperature of 23°C (74°F) and maximums reaching up to 29°C (84°F). This month also sees a higher humidity level at 81% and significant precipitation, with rain falling on 26 days and totaling 287 mm (11.3 in). In contrast, February tends to be slightly cooler, with temperatures averaging around 24°C (75°F) and peaks hitting 32°C (90°F). Although precipitation is slightly higher at 289 mm (11.4 in), it occurs over fewer days—just 23. Additionally, February's humidity is lower at 72%, contributing to a different overall climate experience. For more detailed insights, you can check out Ratnapura weather in February.

In comparing the weather of September and March, both months exhibit warm temperatures, but they also feature notable differences in precipitation and humidity levels. September has a minimum temperature of 19°C (66°F) and an average of 23°C (74°F), while March sees slightly cooler minimum temperatures at 17°C (62°F) and a higher average of 24°C (75°F), peaking at 31°C (88°F). Interestingly, March experiences more rainfall overall, with 384 mm (15.1 in) recorded across 29 days, compared to September's 287 mm (11.3 in) over 26 days. Humidity is another distinguishing factor; September is more humid at 81%, while March has a more comfortable level at 69%. For more specific insights, you can explore Ratnapura weather in March.

September and April each present unique weather characteristics, with September having a slightly cooler average temperature range (19°C to 29°C) compared to April's warmer range (18°C to 31°C). However, April tends to be wetter, receiving more precipitation (415 mm) over marginally fewer days (28 days) than September's 287 mm over 26 days. The humidity in September is notably higher at 81%, making the air feel more oppressive compared to the more comfortable 69% humidity in April. For more detailed insights into April weather, you can check Ratnapura weather in April.

When comparing the weather in September and May, both months exhibit warm temperatures, but September tends to be slightly cooler with an average of 23°C (74°F) compared to May's 24°C (76°F). The maximum temperatures also reflect this trend, with September peaking at 29°C (84°F) while May reaches up to 30°C (86°F). However, May experiences more precipitation than September, with 431 mm (17.0 in) falling over 29 days, compared to September's 287 mm (11.3 in) over 26 days. Humidity levels are quite similar, with September at 81% and May at 79%. For a more detailed look at May's weather, you can visit Ratnapura weather in May.

When comparing the weather in September and June, it’s clear that both months bring warm temperatures with average highs around 29°C (84°F). However, September tends to be slightly warmer in the overnight hours with a minimum temperature of 19°C (66°F), compared to June’s minimum of 20°C (68°F). In terms of precipitation, September is more humid with a total of 287 mm (11.3 in) over 26 days, while June has a lower total of 233 mm (9.2 in) across 28 days. Additionally, the humidity is somewhat higher in June at 85%, compared to 81% in September. For a more detailed look at the weather conditions specific to Ratnapura, you can visit Ratnapura weather in June.

When comparing the weather in September and July, we observe that both months experience high humidity levels at 81%. However, July tends to have slightly lower temperatures, with an average of 24°C (75°F) compared to September's 23°C (74°F). Interestingly, September sees more extreme weather with higher precipitation of 287 mm (11.3 in) over 26 days, while July receives 219 mm (8.6 in) over 29 days. This indicates that although September has slightly less rain days, it generally experiences heavier rainfall. For a closer look at July's climate specifics, you can visit Ratnapura weather in July.

In comparing the weather between August and September, we see some subtle changes. September maintains a similar average temperature to August, hovering around 23°C (74°F), but it has slightly cooler minimum and maximum temperatures of 19°C (66°F) and 29°C (84°F), respectively, compared to August’s 20°C (68°F) low and 28°C (83°F) high. Precipitation is more pronounced in September, with 287 mm (11.3 in) over 26 days, compared to August's 245 mm (9.6 in) over 27 days. The humidity is also slightly lower in September at 81%, compared to 85% in August, indicating that while both months are humid, September may feel a touch more comfortable. For more specific details about August weather in this region, check out Ratnapura weather in August.

In comparing the weather between September and October, both months share similar temperature ranges, with minimums around 19°C (66°F) and averages of 23°C (74°F). However, October experiences slightly lower maximum temperatures, peaking at 28°C (84°F), compared to September’s 29°C (84°F). Rainfall significantly increases in October, accumulating to 475 mm (18.7 in) over 29 days, while September sees 287 mm (11.3 in) over 26 days. Additionally, October's humidity is higher at 89%, compared to September's 81%. For more specific details, you can check Ratnapura weather in October.

September and November exhibit similar average temperatures, with both months hovering around 23°C (74°F), while daily highs can reach up to 29°C (84°F). However, November sees a significant increase in precipitation, totaling 643 mm (25.3 in) compared to September's 287 mm (11.3 in), both occurring over 26 days. This results in November being notably more humid, with levels at 88% versus September's 81%. The dramatic increase in rainfall can make November feel wetter and less comfortable overall. For more detailed information, you can refer to Ratnapura weather in November.

In September, the weather presents warm temperatures with a minimum of 19°C (66°F) and a maximum of 29°C (84°F), averaging around 23°C (74°F). However, it is also a relatively wet month, with a significant precipitation of 287 mm (11.3 in) spread over 26 days and humidity levels at 81%.

In contrast, December maintains a similar average temperature of 23°C (74°F) but features slightly cooler minimum temperatures at 17°C (63°F) and a slightly higher maximum of 30°C (85°F). The month is wetter, with precipitation reaching 402 mm (15.8 in) across 27 days and humidity increasing to 86%. For more specific details about the climatic conditions, visit Ratnapura weather in December.

Compare Ratnapura's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Ratnapura

September in Ratnapura stands out with its unique blend of warmth and moisture, as the region experiences a notable increase in rainfall compared to other months. The combination of high humidity, averaging around 81%, and frequent precipitation—occurring on nearly every day—creates a lush, vibrant landscape typical of this period. While temperatures remain relatively mild, ranging from comfortable to warm, the relentless rain can dominate the weather narrative, transforming the region into a picturesque wonderland. Those interested in exploring Ratnapura during this time will find a climate that's both inviting and dramatic. To learn more about what to expect throughout the year, check out Ratnapura Climate.