September Weather in San Salvador, El Salvador

Last updated: August 21, 2025

September in San Salvador, El Salvador presents a warm and humid climate, with maximum temperatures reaching up to 34°C (93°F) and an average of 26°C (79°F). The month is characterized by frequent rainfall, averaging 301 mm (11.9 in) across 29 days, making it one of the wetter months of the year. Humidity levels soar to around 77%, contributing to a lush and vibrant landscape that highlights the region's natural beauty amidst the warm temperatures. Visitors and residents alike should prepare for both the heat and the rain, embracing the rich atmosphere of this tropical city.

September Temperature in San Salvador

In September, temperatures in San Salvador, El Salvador reflect a gentle transition as the rainy season peaks. With minimums averaging around 20°C (69°F) and a comfortable average temperature of 26°C (79°F), the days remain warm yet pleasant. The maximum temperature reaches 34°C (93°F), slightly cooler than the heights of summer, making it a comfortable time for outdoor explorations. Notably, September maintains a consistent trend from the preceding months, where evenings feel pleasantly mild. As the month progresses, the increasing cloud cover hints at the diminishing heat, paving the way for the refreshing change of October.

September Weather in San Salvador: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in San Salvador, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Salvador, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec777981818078808078787877
Data source: Temperature data for San Salvador 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 San Salvador

In September, San Salvador experiences its peak precipitation, with an impressive 301 mm (11.9 in) of rain typically falling across 29 days of the month. This significant rainfall marks a climactic shift in the wet season, showcasing how the monsoon influences the region's climate as it transitions from the summer months. Notably, September surpasses the preceding summer months—particularly August, known for its heavy rains at 252 mm (9.9 in)—highlighting a surge in precipitation that impacts both daily life and the ecosystem. As October approaches, the rains begin to taper, yet September remains a critical month for replenishing natural water sources and nurturing the lush landscapes of El Salvador.

September Precipitation Trends in San Salvador

The chart displays monthly precipitation patterns in San Salvador, 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. In San Salvador, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec34559269292157252301272587
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in San Salvador

In September, San Salvador experiences a notable humidity level of 77%, maintaining the pattern set in the previous two months of July and August, where humidity peaked at 77% and 79%, respectively. This slight dip from August highlights the city's transition into the heart of the wet season, marked by increased moisture in the air. Following the relatively consistent readings of around 59% earlier in the year from March to May, the rising humidity levels from June onward indicate a shift towards a more humid climate. As San Salvador moves into the latter part of the year, a gradual decline is anticipated, with humidity hovering around 75% and 66% in November and December, respectively, rounding out the year on a slightly drier note.

September Average Humidity in San Salvador

This chart illustrates the average monthly humidity levels in San Salvador, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in San Salvador is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec63%62%59%59%59%68%78%79%77%77%75%67%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in San Salvador

As September rolls in, San Salvador maintains its reputation for extreme sun exposure, boasting a UV Index of 13. This level of intensity has been consistent throughout the summer months, illustrating a trend where the sun's rays remain potent from March through October. With a burn time of just 10 minutes, it's crucial for residents and visitors alike to take protective measures against the sun. Although the index is slightly lower than the peak of 14 seen earlier in the year, caution is still advised. As you explore the vibrant culture and breathtaking landscapes of El Salvador, remember to stay sun-smart. For more detailed insights on UV levels, check out San Salvador UV Index.

Maximum UV Index Levels in San Salvador for September

The chart shows the monthly maximum UV Index (UVI) for San Salvador 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. In September, the maximum UV index in San Salvador typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec11121414141413131313109
Data source: San Salvador 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 San Salvador

September in San Salvador, El Salvador, offers a delightful continuation of the region's abundant sunshine, with 299 hours of bright sunlight. This month showcases a slight dip from the sunny warmth of July and March, which boast peak hours of 328. However, September maintains a strong presence in the annual sunshine trend, sitting comfortably above many months. The post-summer transition subtly invites a hint of cooler temperatures, yet with an average of nearly 10 hours of sunshine daily, it’s the perfect time to explore the city or relax on the beaches. As the year progresses towards its end, the sunlight gradually shifts, but September shines as a warm reminder of summer's lingering embrace.

Monthly Sunshine Duration in San Salvador: September Highlighted

The September sunshine duration represents the total number of hours San Salvador 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.
JanFebMarAprMayJunJulAugSepOctNovDec263h292h328h319h313h284h328h313h299h290h308h326h
Data source: San Salvador September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Salvador During September

As we transition into September in San Salvador, the likelihood of enjoying sunny weather takes a noticeable dip, with only 23% chance of sunshine. This is part of a broader trend as we move from the sunny months of January through March, where chances exceed 60%, down to a period of diminished light in the summer months of June and August, where it plummets to a mere 14% and 15% respectively. While September brings a significant decrease from the earlier months, it's also a precursor to the gradually improving conditions that follow in October and November, highlighting the city’s shifting climate patterns throughout the year. So, while sunny days may be fleeting in September, they herald the return of brighter skies as the year progresses.

Percentage of Sunny Days in September in San Salvador

The chart illustrates the percentage of sunny days in San Salvador 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 San Salvador experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec68%77%70%41%35%14%31%15%23%31%57%72%
Data source: San Salvador September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Salvador in September

As September arrives in San Salvador, daylight remains a generous 12 hours, maintaining the consistent trend observed throughout the summer months. Following the slight increase in daylight from March through August, this duration provides ample opportunity for outdoor adventures and cultural explorations under the vibrant sky. Interestingly, after September, daylight begins to taper off as the city transitions into the shorter days of October and November, when the sunshine dips back to 11 hours. This rhythm of daylight not only enhances the picturesque landscape but also complements the rich experiences that the city offers throughout the year.

Average Daylight Hours in San Salvador for September

The chart illustrates the variation in daylight duration in San Salvador throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 24m11h 41m12h 3m12h 26m12h 45m12h 54m12h 49m12h 32m12h 10m11h 47m11h 28m11h 19m
Data source: San Salvador daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in San Salvador

As September rolls into San Salvador, the breeze begins to soften, with average wind speeds dipping to 1.2 m/s (3 mph). This marks a continuation of the gradual decrease in wind that started in May, reflecting the calmness of the rainy season. It's interesting to note that while the winds are gentle, they have a refreshing quality that offers a welcome respite from the heat. From January to April, the city enjoys slightly brisker winds, averaging about 2.3 m/s (5 mph), which then steadily decline as the year progresses. As September's stillness embraces the city, there’s a sense of tranquility in the air, providing a perfect backdrop for the vibrant culture and beauty of San Salvador.

Average September Wind Speed in San Salvador

The chart displays monthly wind speed patterns in San Salvador, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.32.22.21.91.41.21.51.31.2 m/s1.32.42.0
Data source: San Salvador September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in San Salvador Compares to Other Months

Weather in San Salvador varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in San Salvador, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present contrasting weather conditions. In September, temperatures range from a minimum of 20°C (69°F) to a maximum of 34°C (93°F) with an average of 26°C (79°F). This month is characterized by high humidity at 77% and significant precipitation, with 301 mm (11.9 in) over 29 days. In stark contrast, January sees milder conditions, with temperatures ranging from 15°C (59°F) to a maximum of 36°C (96°F) and an average of 25°C (78°F). This month typically experiences dry weather, with only 3 mm (0.1 in) of precipitation and no rainy days, coupled with lower humidity at 63%. For more details, you can check San Salvador weather in January.

In September, the weather is characterized by warmer temperatures, with a minimum of 20°C (69°F) and a maximum reaching 34°C (93°F), while experiencing significant precipitation of 301 mm (11.9 in) over 29 days. This results in high humidity levels of 77%, creating a muggy atmosphere. In contrast, February offers a slightly cooler minimum temperature of 16°C (60°F) and higher maximum temperatures, peaking at 38°C (101°F). Notably, February is much drier, receiving only 4 mm (0.2 in) of rain over the month with no rainfall days, and lower humidity at 62%. For more details on February weather, you can visit San Salvador weather in February.

In comparing the weather between September and March, we can see some notable differences. September experiences warmer temperatures, with an average of 26°C (79°F) and maximums reaching up to 34°C (93°F), while March has a slightly higher average of 27°C (81°F) but can peak at a scorching 37°C (99°F). However, the most striking contrast lies in the precipitation levels; September is quite wet with 301 mm (11.9 in) of rain over 29 days, whereas March is significantly drier, receiving just 5 mm (0.2 in) of rain across only one day. Additionally, humidity levels are higher in September at 77%, compared to 59% in March. For more detailed insights, check out San Salvador weather in March.

September and April offer contrasting weather patterns. September typically features temperatures ranging from a minimum of 20°C (69°F) to a maximum of 34°C (93°F), with an average of 26°C (79°F). It's also a particularly wet month, receiving 301 mm (11.9 in) of rainfall over 29 days and maintaining a high humidity level of 77%. In comparison, April boasts slightly milder minimum temperatures at 19°C (67°F) and a higher maximum of 38°C (100°F), with an average of 27°C (81°F). Additionally, April is much drier, with only 59 mm (2.3 in) of precipitation over just 12 days and a lower humidity level of 59%. For more detailed information, you can check San Salvador weather in April.

September and May present contrasting yet warm weather patterns. In September, temperatures typically range from a minimum of 20°C (69°F) to a maximum of 34°C (93°F), with an average of 26°C (79°F). This month experiences substantial precipitation, totaling 301 mm (11.9 in) over 29 rainy days, contributing to a high humidity level of 77%. In contrast, May witnesses slightly higher average temperatures, peaking at 36°C (97°F) and maintaining a comfortable minimum of 20°C (69°F), with an average of 27°C (80°F). This month sees lower rainfall at 269 mm (10.6 in) across 26 days and a significantly reduced humidity level of 59%. For more detailed information, you can explore the San Salvador weather in May.

In September, the weather features a minimum temperature of 20°C (69°F) and an average high of 34°C (93°F), coupled with a significant amount of precipitation totaling 301 mm (11.9 in) over 29 days, resulting in a higher humidity level of 77%. In contrast, June presents slightly warmer conditions, with a minimum temperature of 21°C (69°F) and a maximum of 35°C (96°F), along with less rainfall at 292 mm (11.5 in) over 27 days, and lower humidity at 68%. Overall, while both months share similar average temperatures, September is notably wetter and more humid than June. For more detailed information, check San Salvador weather in June.

In comparing the weather of September and July, both months experience high temperatures and humidity levels. September sees a minimum temperature of 20°C (69°F) and an average of 26°C (79°F), with a maximum temperature of 34°C (93°F). In contrast, July has a slightly higher minimum of 21°C (69°F), an average of 27°C (80°F), and peaks at 35°C (96°F). One notable difference is in precipitation; September receives significantly more rain, totaling 301 mm (11.9 in) over 29 days, compared to July's 157 mm (6.2 in) over just 21 days. Remarkably, both months share the same humidity level of 77%. For more detailed climatic information, you can visit San Salvador weather in July.

September experiences slightly cooler average temperatures compared to August, with a minimum of 20°C (69°F) and a maximum of 34°C (93°F), while August reaches a maximum of 35°C (95°F) but has the same minimum temperature. Additionally, September sees increased precipitation, totaling 301 mm (11.9 in) across 29 days, whereas August has 252 mm (9.9 in) over 25 days. Humidity is also slightly lower in September at 77%, compared to 79% in August. For more detailed information about the weather in August, you can check San Salvador weather in August.

September and October exhibit similar temperature patterns, with minimum temperatures remaining steady at around 20°C (69°F). In September, the average temperature is slightly higher at 26°C (79°F) compared to October's 25°C (78°F). Both months share a maximum temperature peak of 34°C (93°F). However, September experiences more rainfall, with a total of 301 mm (11.9 in) across 29 days, whereas October sees a reduction in precipitation to 272 mm (10.7 in) over 28 days, maintaining the same humidity level of 77% in both months. For a detailed look at the weather conditions in October, visit San Salvador weather in October.

September and November exhibit notable differences in weather patterns, particularly in terms of precipitation and temperature. September experiences a higher average temperature of 26°C (79°F) with maximums reaching up to 34°C (93°F), coupled with significant rainfall of 301 mm (11.9 in) over 29 days, contributing to high humidity levels of 77%. In contrast, November offers slightly cooler temperatures with an average of 25°C (78°F) and a similar maximum of 34°C (94°F), but with drastically reduced precipitation at 58 mm (2.3 in) over just 9 days, resulting in a more comfortable humidity level of 75%. For more details on weather in November, you can visit San Salvador weather in November.

In comparing the weather between September and December, September tends to be much wetter and more humid. With an average temperature of 26°C (79°F) and maximums reaching 34°C (93°F), the month experiences considerable rainfall, totaling 301 mm (11.9 in) over 29 days, and a humidity level of 77%. In contrast, December enjoys milder conditions, with average temperatures of 25°C (78°F) and maximums that can reach up to 35°C (95°F). Rainfall decreases significantly, with only 7 mm (0.3 in) recorded over just one day, and humidity drops to 66%. For more detailed information, check out San Salvador weather in December.

Compare San Salvador's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in San Salvador

As September rolls in, San Salvador experiences a noticeable shift in weather, characterized by higher humidity and significant rainfall. This month stands out with its abundant precipitation, impacting daily activities and the landscape alike. The temperatures remain warm, but the frequent showers and overcast skies contrast sharply with the sunnier, drier months preceding it. If you’re planning your visit or looking to learn more about what to expect, check out the comprehensive details presented in San Salvador Climate.