Last updated: August 28, 2025
In September, Sa Pa, Vietnam, experiences a captivating blend of warmth and humidity, with maximum temperatures reaching 31°C (88°F) and an average of 23°C (74°F). As the month unfolds, expect considerable moisture, with 208 mm (8.2 in) of rainfall spread across 25 days, contributing to the lush, verdant landscapes the region is famed for. The humidity hovers around a significant 81%, creating a rich, atmospheric environment that enchants visitors and locals alike. Whether you're trekking through rice terraces or exploring the vibrant local culture, September's weather in Sa Pa offers a unique and invigorating experience.
In September, Sa Pa experiences a delightful transition as temperatures begin to cool from the summer heat, with minimums averaging 15°C (59°F) and maximums peaking at 31°C (88°F). This month sees a balance with an average temperature of 23°C (74°F), inviting visitors to enjoy the crisp mountain air and scenic landscapes. The slight dip from the sweltering months of July and August not only enhances the region's lush greenery but also creates ideal conditions for trekking and exploring. As the rainy season approaches, September's temperatures offer a refreshing respite, making it a perfect time to immerse oneself in the vibrant culture and breathtaking views of this enchanting area.
As September unfolds in Sa Pa, Vietnam, it exhibits a significant shift in precipitation patterns. With 208 mm (8.2 in) of rainfall spread over 25 days, this month sees a notable decrease from the heavy downpours of August, which recorded 455 mm (17.9 in) across 29 days. This trend suggests a gradual transition from the peak rainy season, hinting at a slight reprieve from the relentless summer rains, yet still maintaining a substantial level of moisture. This balance makes September an intriguing time for visitors, as the landscape remains lush and vibrant, while the more moderate rainfall fosters opportunities for exploration amidst the region’s stunning natural beauty.
In September, Sa Pa experiences a notable drop in humidity compared to the oppressive levels of the preceding summer months. With an average humidity of 81%, the air remains quite moist but is significantly less stifling than the sweltering 90% recorded in both July and August. This represents a gradual transition towards the drier conditions of autumn, as humidity levels begin to decrease further in October at 75%. Interestingly, the humidity in September is higher than the earlier months of the year, like January at 57% and April at 53%; however, it marks a pivotal moment in Sa Pa's climatological journey from the peak humidity of summer into the refreshing embrace of fall.
In September, Sa Pa, Vietnam experiences a UV Index of 14, maintaining its extreme exposure category with a rapid burn time of just 10 minutes. This month continues the trend seen over the summer, where the UV Index frequently reached its highest levels, peaking at 15 in May and July. As the region transitions into autumn, the UV Index slightly tapers off but still necessitates caution. Visitors and locals alike should adopt sun protection measures to safeguard against potential skin damage. For detailed UV forecasts throughout the year, check out the Sa Pa UV Index.
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As September unfolds in Sa Pa, Vietnam, it brings 290 hours of radiant sunshine, showcasing a beautiful transition into fall. This month stands out with a notably high number of sunny days, continuing the trend from the sunnier days of May, which recorded an impressive 315 hours. Following the summer, sunshine hours gradually taper off in the coming months, but September resonates with lingering warmth and light, bridging the gap from the vibrant adventures of summer to the cooler embrace of autumn. With sunlight illuminating the terraced rice fields, September is an enchanting time to experience the natural beauty of Sa Pa.
As September arrives in Sa Pa, Vietnam, the likelihood of sunny weather hovers around 30%, showcasing a slight dip from the preceding months of June through August, which feature notoriously low sunshine chances. This month marks a transition from the heavy rains of summer, hinting at a gradual return to brighter days as the region prepares for the autumn months ahead. Compared to December’s 43% chance of sunshine, September's prospects are relatively modest, yet they reflect a hopeful trend towards clearer skies. As travelers venture into this picturesque area, they can embrace the beauty of Sa Pa with the promise of occasional sunny intervals amidst the lush landscape.
In September, Sa Pa, Vietnam enjoys approximately 12 hours of daylight, maintaining the lush vibrancy characteristic of the region as summer transitions into autumn. This month marks the end of a season where daylight peaked in May, June, and July with 13 hours each day. Following this, the daylight duration begins a gradual decline, mirroring the shift in nature as the lush landscapes start to prepare for the cooler months ahead. While October and November see a further reduction to 11 hours, September stands out as a beautiful time when the days are still long enough to explore the breathtaking terraced rice fields and stunning mountain vistas, providing a perfect backdrop for outdoor adventures before the shorter days set in.
As the September winds sweep across Sa Pa, Vietnam, a notable calmness settles in with an average wind speed of just 1.0 m/s (2 mph). This slight dip marks a gentle shift from the summer months, reflecting a transition towards the cooler autumn air. Throughout the year, wind speeds in Sa Pa have shown a fascinating pattern—generally ranging between 1.0 to 1.3 m/s—with September experiencing one of its more tranquil moments. As nature prepares for the vibrant colors of fall, the soft breeze in September invites visitors to savor the serene beauty of this mountainous region, making it an ideal time for exploration and reflection.
Weather in Sa Pa varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Sa Pa, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present a stark contrast in weather conditions. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 31°C (88°F), with an average of 23°C (74°F). This month experiences higher humidity at 81% and significant rainfall, accumulating 208 mm (8.2 in) over 25 days. In contrast, January offers cooler temperatures, with a minimum of 2°C (35°F) and a maximum of 26°C (78°F), averaging 14°C (57°F). The precipitation in January is notably lower, totaling 101 mm (4.0 in) over just 13 days, and the humidity drops to 57%. For more detailed information on January weather in Sa Pa, check out Sa Pa weather in January.
The weather in September features significantly warmer temperatures, with a minimum of 15°C (59°F) and an average of 23°C (74°F), peaking at a maximum of 31°C (88°F). In contrast, February is much cooler, experiencing a minimum of 4°C (39°F) and an average of 14°C (58°F), with a maximum of 27°C (82°F). Additionally, September sees a higher level of precipitation, totaling 208 mm (8.2 in) over 25 days, while February has only 88 mm (3.5 in) spread across 17 days. The humidity also differs, with September at 81% and February at 67%. For more details, you can check out Sa Pa weather in February.
September and March present contrasting weather patterns. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 31°C (88°F), with an average of 23°C (74°F). This month also experiences significant rainfall, totaling 208 mm (8.2 in) over 25 days, coupled with high humidity of 81%. In contrast, March sees cooler temperatures, with a minimum of 10°C (50°F) and a maximum of 30°C (86°F), while the average temperature is a mild 18°C (65°F). Precipitation is lower at 162 mm (6.4 in) across 22 days, and humidity drops to a more comfortable 58%. For more detailed information, you can check Sa Pa weather in March.
In comparing the weather conditions between September and April, both months showcase a significant variation in temperature and humidity. September tends to be warmer, with average temperatures ranging from a minimum of 15°C (59°F) to a maximum of 31°C (88°F), while April features cooler temperatures, with averages between 8°C (47°F) and 33°C (92°F). Precipitation levels are quite similar; September receives approximately 208 mm (8.2 in) over 25 days, while April has slightly higher rainfall at 218 mm (8.6 in) across 21 days. Notably, September is characterized by higher humidity levels at 81%, in contrast to April's more comfortable 53%. For more detailed insights on the weather in April, you can visit Sa Pa weather in April.
In comparing the weather of September and May, we notice that both months share a similar average temperature of 23°C (74°F), yet their extremes differ significantly. September reaches a maximum of 31°C (88°F), while May can soar up to 34°C (93°F), making May the slightly warmer month overall. While precipitation is quite significant in both months, September has a higher total rainfall of 208 mm (8.2 in) over 25 days compared to May's 172 mm (6.8 in) over 26 days. Additionally, humidity in September is notably higher at 81%, while May enjoys a more comfortable 69%. For more detailed information, you can check Sa Pa weather in May.
In comparing the weather in September and June, we see that both months share similar maximum temperatures, peaking at around 31°C (88°F) to 89°F. However, September tends to be slightly cooler, with an average temperature of 23°C (74°F), compared to June's average of 24°C (75°F). Rainfall is significantly more prominent in June, with 303 mm (11.9 in) of precipitation over 29 days, contrasting with September's 208 mm (8.2 in) over 25 days. Humidity levels are also comparable, with September at 81% and June slightly higher at 83%. For more detailed insights on June weather, you can visit Sa Pa weather in June.
In comparing the weather of September and July, we observe notable differences in temperature and precipitation patterns. September tends to be slightly cooler, with an average temperature of 23°C (74°F) and maximum highs reaching 31°C (88°F), while July averages a bit warmer at 24°C (75°F) with similar maximums of 32°C (90°F). However, July experiences significantly higher precipitation, totaling 350 mm (13.8 in) over 30 days compared to September's 208 mm (8.2 in) across 25 days, leading to a more humid environment in July, with humidity levels hitting 90% compared to September's 81%. For more detailed information about July weather, you can check Sa Pa weather in July.
In comparing the weather of September to that of August, September exhibits a noticeable drop in minimum temperatures, with a low of 15°C (59°F) compared to August's minimum of 20°C (68°F). Despite the average temperature being slightly higher in August at 24°C (75°F) versus 23°C (74°F) in September, both months share similar maximum temperatures of 31°C (88°F). One of the most significant differences is in precipitation; September experiences 208 mm (8.2 in) over 25 days, while August sees a much higher total of 455 mm (17.9 in) over 29 days. Additionally, humidity levels remain elevated in both months, although September is marginally lower at 81% compared to August's 90%. For more detailed insights into the weather patterns, you can explore Sa Pa weather in August.
September typically invites warmer weather with average temperatures around 23°C (74°F) and highs reaching up to 31°C (88°F), while also experiencing significant rainfall of 208 mm (8.2 in) over 25 days. The humidity during this month is relatively high at 81%, making it feel quite muggy. In contrast, October marks a transition to cooler conditions, with average temperatures dropping to 20°C (69°F) and maximums of 29°C (84°F). Although it still sees notable precipitation, with 178 mm (7.0 in) over 21 days, the humidity decreases to 75%, creating a more comfortable atmosphere. For a detailed look at October weather, check out Sa Pa weather in October.
September and November showcase a distinct contrast in weather patterns. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 31°C (88°F), with an average of 23°C (74°F). The month experiences considerable precipitation, totaling 208 mm (8.2 in) over 25 days, resulting in high humidity levels at 81%. In stark contrast, November brings cooler temperatures, with a minimum of 8°C (47°F) and a maximum of 27°C (80°F), averaging at 17°C (64°F). Precipitation drops significantly to 66 mm (2.6 in) over just 14 days, and humidity levels decrease to 74%. For more specific details on the weather in Sa Pa during this month, check out Sa Pa weather in November.
September and December exhibit contrasting weather patterns. September, characterized by warmer temperatures, features a minimum of 15°C (59°F) and can rise to a maximum of 31°C (88°F), with an average of 23°C (74°F). The month is also quite humid, with humidity levels at 81% and significant precipitation totaling 208 mm (8.2 in) over 25 days. In contrast, December experiences cooler temperatures, with a minimum of 2°C (36°F) and a maximum of 26°C (78°F), averaging only 14°C (57°F). Precipitation is notably lower at 65 mm (2.6 in) over just 10 days, and humidity decreases to 69%. For more specific information on the weather in Sa Pa during December, you can visit Sa Pa weather in December.
As September unfolds in Sa Pa, the weather showcases a unique blend of warmth and moisture, marking a transition into the autumn season. With moderately high temperatures and elevated humidity levels, this month is characterized by an increased likelihood of rainfall, often manifesting as drizzles rather than heavy downpours. Unlike the drier months that precede it, September's 81% humidity and 208 mm of precipitation over about 25 days create a lush and vibrant landscape, enhancing the region's natural beauty. This mix of temperature and rain provides a refreshing atmosphere, setting Sa Pa apart from the typically drier months earlier in the year. To explore more about how this region's climate evolves throughout the year, check out Sa Pa Climate.