Last updated: August 21, 2025
September in Riobamba, Ecuador offers a unique blend of cool temperatures and occasional rainfall. With a maximum of 20°C (68°F) and an average of 9°C (49°F), the weather can vary significantly throughout the day, dropping to a chilly minimum of -1°C (31°F) at night. The month sees around 46 mm (1.8 inches) of precipitation spread over 12 days, creating a humid atmosphere with an average humidity of 63%. This combination of cool temperatures and moisture makes September an intriguing time to experience Riobamba's rich landscape and vibrant culture.
In September, Riobamba, Ecuador begins to feel a subtle shift as temperatures slightly rise compared to the preceding months. With minimums dipping to around -1°C (31°F) and average temperatures reaching 9°C (49°F), the chill of winter lingers. However, the maximum temperature creeps up to 20°C (68°F), marking the onset of a warmer spell. This gradual increase not only brightens the ambiance but also hints at the approaching transition towards more temperate conditions in October. As September unfolds, locals and visitors alike can enjoy these mild temperatures, ideal for exploring the captivating scenery and rich culture of this Andean gem.
In September, Riobamba, Ecuador, experiences a noticeable dip in precipitation compared to the preceding months, totaling 46 mm (1.8 in) over 12 days. This slight decline marks a transition from the heavier rains of previous months, particularly the peaks seen in March and April. While the monthly rainfall in September is relatively low, it represents the tail end of the rainy season, setting the stage for a gradual shift towards drier conditions as the year progresses. This trend illustrates the unique climate dynamics of Riobamba, where even in the wet season, variability in precipitation can lead to unexpected dry spells.
In Riobamba, Ecuador, September marks a notable dip in humidity, averaging at 63%, significantly lower than the preceding months. This trend reflects a gradual decline from the high humidity levels often experienced throughout the year, including peaks of 92% in May and 90% in June. Interestingly, this drop in September paves the way for the arrival of the drier season, as the city transitions from the humid embrace of winter to a refreshing atmosphere. Following this autumn-like shift, humidity levels begin to rise again in October, suggesting a dynamic interplay between the seasons in this Andean region.
In September, the UV Index in Riobamba, Ecuador remains notably high, reaching a level of 17, categorized as extreme. This trend of extreme UV exposure is consistent throughout much of the year, with the highest recordings seen from January to April, where values soar to 19. Even as the seasons shift, September's UV levels indicate a commitment to sun safety, necessitating limited exposure times of just 10 minutes to prevent burns. As autumn approaches, it’s essential for residents and visitors alike to remain vigilant with sun protection. For detailed insights on UV exposure in different months, visit Riobamba UV Index.
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In September, Riobamba basks in an impressive 297 hours of sunshine, contributing to the city's vibrant atmosphere. This month showcases a slight decrease from the peak of 326 hours in August, yet it remains a significant contributor to the region’s rich tapestry of sun-drenched days. Following a steady climb during the mid-year months, where June and July delivered 275 and 319 hours respectively, September continues the trend of abundant daylight. As the year advances into the softer golden hues of October, which enjoys 251 hours, September stands out as a sunny transitional moment, embracing the lingering warmth before the cooler months set in. Overall, the sunshine data highlights a remarkable seasonal shift, where the high-altitude charm of Riobamba thrives under the sun's generous embrace.
In Riobamba, Ecuador, September marks a notable shift towards sunnier weather, boasting a 27% chance of sunny days—the highest probability of the entire year. This increase in sunshine follows a generally wet winter season, with the months leading up to September, particularly June and August, showing moderate sun exposure at 19% and 22%, respectively. As the region transitions from the cooler, cloudier months to the warmer spring, residents and visitors can look forward to more vibrant days filled with sunshine, making September an inviting time to explore the stunning landscapes of the Ecuadorian highlands.
In Riobamba, Ecuador, September experiences a remarkable consistency in daylight duration, with 12 hours of sunlight gracing the city—just like every other month of the year. This steady daylight pattern underscores the region's equatorial location, where the sun rises and sets around the same time throughout the year. Residents and visitors alike can enjoy a harmonious balance of light and dark, allowing for a wealth of outdoor activities and a vibrant lifestyle, regardless of the month. As September rolls in, the enchanting cycle of day and night remains unchanged, inviting everyone to bask in the extended hours of brightness.
In September, Riobamba experiences a gentle breeze, with average wind speeds of 2.2 m/s (5 mph). This marks a continuation of the slightly elevated winds seen in the preceding months of July and August, where the strongest winds of the year peak. Notably, the wind speeds begin to trend downward after September, dropping to 1.5 m/s (3 mph) in October, suggesting a shift towards the calmer, cooler months as the year progresses. The increasing wind pattern from April through July highlights an interesting seasonal dynamic, with the winds reaching their zenith in mid-year, inviting a refreshing pause before the calmer fall settles in.
Weather in Riobamba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Riobamba, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present notable differences in weather conditions. In September, temperatures range from a minimum of -1°C (31°F) to a maximum of 20°C (68°F), with an average of 9°C (49°F). The month sees 46 mm (1.8 in) of precipitation spread over 12 days, accompanied by a humidity level of 63%. Conversely, January experiences slightly warmer temperatures, with a minimum of 1°C (34°F) and a maximum of 18°C (65°F), while the average remains at 9°C (48°F). However, it is significantly wetter, receiving 141 mm (5.5 in) of rain over 21 days, and the humidity rises to 82%. For a deeper look into January weather specifics, you can visit Riobamba weather in January.
September and February showcase distinct differences in weather conditions despite having similar average temperatures. In September, temperatures range from a chilly -1°C (31°F) at night to a pleasant max of 20°C (68°F) during the day, with relatively moderate precipitation of 46 mm (1.8 in) over about 12 days. In contrast, February experiences slightly cooler maximum temperatures, peaking at 18°C (65°F), but significantly increased precipitation, averaging 172 mm (6.8 in) over 24 days, accompanied by higher humidity levels at 79%. This makes February not only wetter but also more humid, providing a stark contrast to the drier weather of September. For more detailed information, you can check Riobamba weather in February.
September and March exhibit distinct weather patterns. In September, temperatures range from a minimum of -1°C (31°F) to a maximum of 20°C (68°F), with an average temperature of 9°C (49°F). The month experiences relatively low precipitation, totaling 46 mm (1.8 in) over about 12 days, and humidity levels average around 63%. In contrast, March sees slightly warmer conditions with a minimum temperature of 2°C (35°F) and a maximum of 18°C (65°F), while the average remains similar at 9°C (48°F). However, March is considerably wetter, receiving a notable 231 mm (9.1 in) of rain over 28 days and higher humidity levels at 86%. For more specific insights into the climate during this month, you can check out Riobamba weather in March.
When comparing the weather in September and April, both months exhibit similar average temperatures, hovering around 9°C (49°F). However, September sees milder extremes with a maximum temperature of 20°C (68°F) compared to April’s slightly cooler maximum of 18°C (65°F). Precipitation levels tell a different story, as April is significantly wetter, receiving 182 mm (7.2 in) over 27 days, compared to September’s 46 mm (1.8 in) spread over just 12 days. Additionally, April boasts higher humidity levels at 86%, compared to September’s 63%. For more detailed information about April weather, you can visit Riobamba weather in April.
In comparing the weather of September and May, we find some intriguing differences. September typically ranges from a minimum temperature of -1°C (31°F) to a maximum of 20°C (68°F), with an average of 9°C (49°F). The month receives about 46 mm (1.8 in) of precipitation over approximately 12 days, and the humidity averages around 63%.
In contrast, May experiences slightly milder temperatures, with a minimum of 0°C (33°F) and a maximum of 18°C (65°F), while maintaining the same average of 9°C (49°F). However, May is considerably wetter, with a total precipitation of 138 mm (5.4 in) over about 24 days and much higher humidity levels at 92%. For more detailed insights, you can check out Riobamba weather in May.
In comparing the weather of September and June, we see notable differences in temperature and precipitation. September typically experiences a broader temperature range, with minimums of -1°C (31°F) and maximums reaching 20°C (68°F), resulting in a comfortable average of 9°C (49°F). In contrast, June sees slightly milder temperatures, with a minimum of 0°C (32°F) and a maximum of 17°C (63°F), yielding an average temperature of only 8°C (47°F).
Additionally, June is significantly wetter, receiving about 100 mm (3.9 in) of precipitation over approximately 20 days, compared to September's 46 mm (1.8 in) spread over just 12 days. The humidity is also notably higher in June at 90%, compared to 63% in September. For more detailed insights into June weather, you can visit Riobamba weather in June.
In comparing the weather between July and September, September tends to be slightly warmer with an average temperature of 9°C (49°F) compared to July's 8°C (46°F). Both months experience similar minimum temperatures of -1°C (31°F), but September reaches a higher maximum of 20°C (68°F) versus July’s 18°C (65°F). While September has less precipitation overall at 46 mm (1.8 in) and fewer rainy days (12 days) compared to July’s 67 mm (2.6 in) across 16 days, the humidity is lower in September at 63%, compared to July’s 72%. For more specific details, you can check out Riobamba weather in July.
September's weather is characterized by a slightly cooler temperature range, with a minimum of -1°C (31°F) and an average of 9°C (49°F), compared to August's minimum of 0°C (32°F) and average of 8°C (47°F). The maximum temperatures in September reach up to 20°C (68°F), which is marginally higher than August's peak of 19°C (66°F). Additionally, September sees increased precipitation, totaling 46 mm (1.8 in) over 12 days, while August has 40 mm (1.6 in) over 10 days, making it a wetter month overall. Humidity levels also rise slightly in September to 63%, up from August's 60%. For more detailed information, check Riobamba weather in August.
September and October present notable differences in weather patterns. In September, temperatures range from a minimum of -1°C (31°F) to a maximum of 20°C (68°F), with an average of 9°C (49°F). The month experiences 46 mm (1.8 in) of precipitation over 12 days and a humidity level of 63%. In contrast, October sees a slight increase in temperature with a minimum of 0°C (33°F) and a maximum of 21°C (70°F), maintaining the same average of 9°C (48°F). However, precipitation significantly rises to 116 mm (4.6 in) over 22 days, and humidity levels also increase to 76%. The transition from September to October indicates a wetter month, which can be explored further in detail here: Riobamba weather in October.
In comparing the weather between September and November, there are notable differences. September experiences cooler temperatures, with a minimum of -1°C (31°F) and a maximum of 20°C (68°F), accompanied by moderate precipitation of 46 mm (1.8 in) over 12 days and a relative humidity of 63%. In contrast, November sees slightly higher minimum temperatures starting at 0°C (33°F) and an average temperature similar to September at 9°C (48°F), but with a maximum of 19°C (67°F). However, November is much wetter, receiving 170 mm (6.7 in) of precipitation over 26 days and a much higher humidity level of 85%. For more detailed insights, you can check Riobamba weather in November.
September and December both showcase relatively mild average temperatures, hovering around 9°C (49°F). However, a closer look reveals some notable differences in their weather patterns. September experiences cooler minimum temperatures, dropping to -1°C (31°F), while December sees a slightly warmer minimum at 2°C (37°F). Precipitation also varies significantly; September has 46 mm (1.8 in) over 12 days, whereas December dramatically increases to 154 mm (6.1 in) across 27 days, reflecting a much wetter month. Additionally, humidity levels rise noticeably in December, hitting 86% compared to September's 63%. For a detailed look at December weather, check out Riobamba weather in December.
In September, Riobamba experiences a notable shift in weather patterns compared to other months. With temperatures ranging from cool to mild, it offers a refreshing contrast to the heat of the summer. This month sees a bit more rain, as 12 days of precipitation contribute to a total of 46 mm, making it one of the wetter periods of the year. The 63% humidity adds a touch of dampness in the air, creating a distinct ambiance that sets September apart. For those planning a visit, it’s an excellent time to experience the lush rejuvenation of the landscape. Learn more about the fascinating nuances of weather throughout the year by checking out Riobamba Climate.