September Weather in Unawatuna, Sri Lanka

Last updated: March 19, 2025

In September, Unawatuna, Sri Lanka experiences a tropical climate marked by warm temperatures and significant rainfall. The maximum temperature reaches a comfortable 29°C (84°F), while the average hovers around 27°C (80°F), and the minimum can dip to 25°C (77°F). This warm atmosphere is accompanied by high humidity levels at 82%, creating a sultry environment. Visitors should prepare for frequent rain, as September sees an average precipitation of 235 mm (9.3 in) spread over 27 days, making it one of the wetter months. While the lush greenery thrives, those venturing to Unawatuna should embrace the vibrant monsoon season and pack accordingly for the delightful, albeit wet, tropical experience.

September Temperature in Unawatuna

In September, Unawatuna, Sri Lanka welcomes mild temperatures that are quite consistent with earlier months, showcasing a minimum of 25°C (77°F) and an average around 27°C (80°F). The maximum temperature reaches a comfortable 29°C (84°F), making it an ideal time for beachgoers and nature lovers alike. As the month transitions, the warmth remains steady, hinting at the lingering influence of the tropical climate. This seamless blend of warmth and humidity creates a lively atmosphere for visitors without the extreme heat of summer, echoing the destination's charm throughout the year.

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

The chart illustrates September temperature patterns in Unawatuna, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec808181828281818080808080
Data source: Temperature data for Unawatuna 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 Unawatuna

In September, Unawatuna, Sri Lanka experiences a substantial amount of rainfall, with precipitation totaling approximately 235 mm (9.3 in) over 27 days. This marks a continuation of the wet season, following an already significant August. Interestingly, this drop in total precipitation compared to May and June—the peak months—suggests a slight easing of the monsoon intensity. However, the persistent rain can still transform the landscape, enriching the lush greenery that characterizes the region. As the month transitions into October, the rainfall is set to rise again, with October typically bringing around 259 mm (10.2 in), maintaining the rhythm of the tropical climate that defines this beautiful coastal area.

September Precipitation Trends in Unawatuna

The chart displays monthly precipitation patterns in Unawatuna, 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.
JanFebMarAprMayJunJulAugSepOctNovDec606289137289237207219235259223151
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Unawatuna

In September, Unawatuna experiences a humidity level of 82%, maintaining a trend of high moisture that begins in the earlier summer months. Following a slight dip in May, humidity levels rebound, reaching their peak in June before slightly tapering off through the late summer. As the year progresses, the humidity remains consistently high, with September mirroring the humid conditions of both August and the upcoming October. This pattern reflects the tropical climate of the region, making September a month characterized by warmth and a noticeable moisture that influences daily life and activities in this beautiful coastal town.

September Average Humidity in Unawatuna

This chart illustrates the average monthly humidity levels in Unawatuna, 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%77%77%77%76%83%81%83%82%83%81%82%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Unawatuna

In September, the UV Index in Unawatuna, Sri Lanka, reaches a notable 14, categorizing exposure as extreme and indicating a brisk burn time of just 10 minutes. This trend of high UV levels continues throughout the year, as seen from January's peak of 15 to October's slight decrease to 13. Remarkably consistent, the region maintains an extreme exposure level from January through September, urging residents and visitors alike to take necessary precautions when outdoors. As the sun shines brightly over this beautiful coastal town, understanding the UV patterns is crucial for safe skin exposure. For more insights on the UV Index, check out Unawatuna UV Index.

Maximum UV Index Levels in Unawatuna for September

The chart shows the monthly maximum UV Index (UVI) for Unawatuna 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.
JanFebMarAprMayJunJulAugSepOctNovDec131415151412131414131111
Data source: Unawatuna 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 Unawatuna

September in Unawatuna, Sri Lanka, offers a delightful blend of sunshine and warmth, boasting 317 hours of sunlight. While the month may see a slight dip from the sun-kissed highs of July and August, which recorded 339 and 336 hours respectively, it still provides plenty of radiant days for beach lovers and adventurers alike. This trend of plentiful sunshine continues from the earlier months of the year, with March peaking at 334 hours. As summer gently transitions into autumn, September maintains a loyal offering of golden rays, inviting visitors to bask in its serenity before the sun begins to retreat in November. Overall, the island remains a splendid choice for sun-seekers, ensuring that every moment is filled with warmth and light.

Monthly Sunshine Duration in Unawatuna: September Highlighted

The September sunshine duration represents the total number of hours Unawatuna 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.
JanFebMarAprMayJunJulAugSepOctNovDec273h311h334h332h329h333h339h336h317h315h294h309h
Data source: Unawatuna September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Unawatuna During September

In September, Unawatuna, Sri Lanka, experiences a 23% chance of sunny weather, which reflects a slight rebound from the dreary summer months. As the monsoon season starts to ease, this percentage is an improvement compared to the rain-soaked months of July and August, where the likelihood of sunshine dropped to 16% and a mere 8%, respectively. However, the sunniest period is still ahead, as October and November follow closely with chances of 19% and 18%. This trend suggests that while September may not be the sunniest month, it signifies a gradual shift towards clearer skies and better opportunities for enjoying Unawatuna's stunning beaches.

Percentage of Sunny Days in September in Unawatuna

The chart illustrates the percentage of sunny days in Unawatuna 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 Unawatuna experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec20%42%34%48%18%24%16%8%23%19%18%49%
Data source: Unawatuna September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Unawatuna in September

In September, Unawatuna, Sri Lanka basks in an average of 12 hours of daylight, maintaining the steady rhythm established over the preceding months. This consistency in daylight duration, stretching from March through September, indicates a delightful equilibrium that allows both locals and visitors to fully enjoy the vibrant coastal landscape. As the days progressively shorten leading into October, the transition stands in contrast to the preceding months, which have graced the shores with ample sunlight. This gradual shift marks the beginning of a seasonal change, inviting a refreshing anticipation for the cooler months ahead. Overall, September serves as a wonderful culmination of summer's generous daylight, providing abundant time for exploration and relaxation under the Sri Lankan sun.

Average Daylight Hours in Unawatuna for September

The chart illustrates the variation in daylight duration in Unawatuna throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 48m11h 55m12h 4m12h 14m12h 22m12h 26m12h 24m12h 17m12h 7m11h 58m11h 50m11h 46m
Data source: Unawatuna daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Unawatuna

As September unfolds in Unawatuna, Sri Lanka, the gentle caress of the sea breeze becomes a familiar companion, with an average wind speed of 5.8 m/s (13 mph). This month reflects a slight dip from the prevailing winds of July and August, which peak at around 6.8 m/s (15 mph) and 5.9 m/s (13 mph), respectively. The waning summer winds signal a transition towards the more tranquil months ahead. Notably, the wind speeds during these late summer months are significantly higher than those in the earlier part of the year, where January and February see softer breezes around 2.3 m/s (5 mph). As the year draws to a close, a gradual decrease in wind speeds emerges, hinting at the serene atmosphere that envelops Unawatuna in the cooler months. This shift not only enhances the idyllic beach setting but also invites relaxation, making September a perfect time to unwind by the shore.

Average September Wind Speed in Unawatuna

The chart displays monthly wind speed patterns in Unawatuna, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.32.12.53.14.96.26.85.95.8 m/s5.25.02.2
Data source: Unawatuna September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Unawatuna Compares to Other Months

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

In comparing the weather of September and January, both months maintain an average temperature of around 27°C (80°F), but January tends to have slightly higher maximum temperatures, reaching up to 31°C (88°F). September, on the other hand, experiences notably more precipitation, with 235 mm (9.3 in) over 27 days, while January sees significantly less rain, at 60 mm (2.4 in) over just 11 days. Humidity levels are fairly similar, hovering around 80% in January and slightly higher at 82% in September. For more detailed information about weather conditions specific to January, you can check Unawatuna weather in January.

In comparing the weather between September and February, we observe that September is characterized by slightly warmer temperatures, with a minimum of 25°C (77°F), an average of 27°C (80°F), and a maximum of 29°C (84°F). In contrast, February features a similar minimum of 24°C (76°F) but has a higher maximum temperature of 32°C (89°F).

Precipitation is a significant factor, as September experiences much heavier rainfall, totaling 235 mm (9.3 in) over 27 days, while February sees a much drier climate with only 62 mm (2.4 in) over 12 days. Humidity levels in September are higher at 82%, compared to February’s 77%, leading to a more humid ambiance in the early fall. For more detailed insights about the weather conditions in February, you can visit Unawatuna weather in February.

September and March exhibit notable differences in weather patterns. Both months have an average temperature of 27°C (80°F), but September tends to feel more humid, with a high humidity level of 82% compared to March's 77%. While September experiences a significant amount of rainfall, totaling 235 mm (9.3 in) over 27 days, March offers a milder precipitation of 89 mm (3.5 in) across just 17 days. Additionally, March can feel warmer at its maximum temperature of 32°C (89°F), making the transition from winter to spring more pronounced. For more details, you can refer to Unawatuna weather in March.

When comparing the weather in September and April, both months exhibit warm temperatures, with September having a slightly lower average of 27°C (80°F) compared to April's 28°C (82°F). However, April enjoys higher maximum temperatures, reaching up to 31°C (89°F), while September peaks at 29°C (84°F). Precipitation is notably higher in September, totaling 235 mm (9.3 in) over 27 days, making it a wetter month compared to April’s 137 mm (5.4 in) across 24 days. Additionally, humidity levels in September are higher at 82%, whereas April's humidity is slightly lower at 77%. For a more detailed look at the weather patterns, you can check Unawatuna weather in April.

September and May both experience warm temperatures, with September showing a slight variation in daily averages. In September, the minimum temperature is around 25°C (77°F), with an average of 27°C (80°F) and a maximum of 29°C (84°F), while May tends to be a bit warmer, with minimums also at 25°C (78°F), an average of 28°C (82°F), and highs reaching 31°C (87°F). Precipitation levels are notably high in both months, with September receiving 235 mm (9.3 in) over 27 days, slightly less than May, which experiences 289 mm (11.4 in) across 28 days. Additionally, while September has higher humidity levels at 82%, May's humidity is a touch lower at 76%. For a detailed look at May's weather patterns, check out Unawatuna weather in May.

In comparing the weather of September and June, we find that both months feature a similar temperature range, with minimums at 25°C (77°F) and averages hovering around 27°C (80°F to 82°F). However, September tends to be slightly cooler, with a maximum of 29°C (84°F), compared to June's peak of 30°C (85°F). Precipitation levels are nearly identical, with September receiving 235 mm (9.3 in) over 27 days, while June sees a marginally higher 237 mm (9.3 in) across 28 days. Humidity levels are also similar, with September at 82% and June at 83%. For a deeper insight into June weather specifics, you can refer to Unawatuna weather in June.

In both September and July, the weather remains consistently warm, with similar temperature ranges; both months feature a minimum temperature of 25°C (77°F), an average of 27°C (80°F for September and 81°F for July), and a maximum reaching 29°C (84°F in September and 85°F in July). However, September tends to be slightly wetter, receiving 235 mm (9.3 in) of precipitation over 27 days compared to July's 207 mm (8.1 in) across 28 days. Humidity levels are also quite similar, with September at 82% and July slightly lower at 81%. For more detailed information, you can view Unawatuna weather in July.

In comparing the weather between August and September, we see that both months share similar temperature patterns, with minimums around 25°C (77°F), averages at 27°C (80°F), and maximums peaking at 29°C (84°F). However, September experiences slightly higher precipitation levels, totaling 235 mm (9.3 in) over 27 days, compared to August’s 219 mm (8.6 in) over the same number of days. Humidity remains consistent in both months at 82%, maintaining the characteristic tropical environment. For more detailed information, you can visit Unawatuna weather in August.

September and October exhibit similar temperature profiles, with both months maintaining minimums of 25°C (77°F), averages of 27°C (80°F), and maximums of 29°C (84°F). However, October tends to be slightly wetter, with precipitation increasing to 259 mm (10.2 in) over 28 days, compared to September's 235 mm (9.3 in) across 27 days. Humidity also sees a slight uptick, with October averaging 83% compared to September's 82%. For those planning a visit, this trend highlights the need for rain gear in October, as reflected in the detailed forecast at Unawatuna weather in October.

September and November offer a warm and humid climate, characteristic of tropical weather. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 29°C (84°F), with an average of 27°C (80°F). The month sees significant rainfall, totaling 235 mm (9.3 in) over 27 days, and a humidity level of 82%. In contrast, November presents slightly warmer conditions with temperatures reaching a maximum of 30°C (86°F) and a minimum of 24°C (75°F), maintaining the same average of 27°C (80°F). Precipitation in November is somewhat lower at 223 mm (8.8 in) over 25 days, with humidity remaining comparable at 81%. For more specific details about the weather in November, visit Unawatuna weather in November.

In September, the weather remains quite warm, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 29°C (84°F) and an average of 27°C (80°F). However, it's also the wettest month, with substantial rainfall totaling 235 mm (9.3 in) over 27 days, saturating the air with humidity levels at 82%.

In contrast, December sees similar average temperatures, with a minimum of 25°C (77°F) and a maximum of 30°C (85°F). The precipitation decreases significantly to 151 mm (5.9 in) over just 19 days, while humidity remains steady at 82%. This change makes December a more pleasant month overall, as the combination of slightly warmer days and less rain offers improved conditions for outdoor activities. For more details, visit Unawatuna weather in December.

Compare Unawatuna's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Unawatuna

September in Unawatuna ushers in a unique blend of warmth and humidity, with temperatures typically hovering around a pleasant average of 27°C. However, this month stands out due to its significant rainfall, as it experiences one of the highest precipitation totals of the year, making it a notably wetter period with about 27 rainy days. This combination of high humidity and ample rainfall creates a lush, vibrant landscape that is distinct from the drier months that precede it. If you're curious about how this weather patterns compare throughout the year, you can explore more at Unawatuna Climate.