Last updated: April 22, 2025
In Monterrey, Mexico, September ushers in a blend of warm temperatures and notable humidity. With maximum highs reaching 37°C (99°F) and an average of 26°C (78°F), the month presents a sultry atmosphere, particularly with humidity levels hovering around 72%. Temperatures can dip to a refreshing 16°C (61°F) during cooler nights. However, this month is also characterized by an average precipitation of 104 mm (4.1 in) over 10 days, marking it as a time of significant rainfall amidst the heat. Overall, September in Monterrey is a season of vibrant contrasts, balancing warmth and wetness.
In September, Monterrey, Mexico, experiences a delightful shift in temperatures, marking a transitional phase as summer begins to wane. With a minimum temperature of 16°C (61°F) and an average of 26°C (78°F), the city embraces a warm and comfortable climate, perfect for outdoor activities. As the month progresses, the maximum temperatures peak at 37°C (99°F), providing a taste of lingering summer heat. This gradual cooling trend sets the stage for the upcoming autumn months, making September an inviting time to explore Monterrey's vibrant culture and scenic landscapes. Whether enjoying a late summer adventure or savoring the mild evenings, visitors are sure to appreciate the pleasant weather that characterizes this dynamic month.
In September, Monterrey experiences a significant uptick in rainfall, with precipitation soaring to 104 mm (4.1 in) across approximately 10 days. This marks a dramatic contrast to the preceding months, especially after the notably dry August, which received only 9 mm (0.3 in). As the city transitions into fall, the rainfall not only replenishes the parched landscape but also highlights September as the wettest month of the year. This trend suggests a shift towards a more humid climate, paving the way for the lush greenery that characterizes Monterrey in the autumn months, while providing relief after the preceding summer heat.
September in Monterrey, Mexico, sees a notable increase in humidity, reaching 72%—a rise from the drier summer months of July and August, which averaged 57% and 58%, respectively. This uptick marks a transitional shift as the region prepares for the autumn season. Following the peak summer heat, September's humidity begins to creep upward, paving the way for even higher levels in the approaching months of October and November, which boast 76% and 81% humidity, respectively. Notably, while January typically begins the year with the highest humidity at 75%, September serves as a reminder of the lingering effects of summer’s warmth, hinting at a gradual return to the more humid conditions of winter.
In September, Monterrey, Mexico, continues to experience extreme UV radiation, with a UV Index of 12 and a burn time of just 10 minutes. This reflects a slight decrease from the peak 13 observed in the summer months of June through August, yet it remains a critical time for sun safety. As the autumn approaches, the UV exposure remains intense, necessitating precautions such as wearing sunscreen and protective clothing. It's clear that while September marks the transition towards milder temperatures, the UV levels still demand respect and awareness. For more details on UV exposure, visit Monterrey UV Index.
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September in Monterrey, Mexico, brings a delightful transition from the sun-drenched days of summer to the gentler warmth of autumn. With 283 hours of sunshine, it offers a notable dip compared to the peak of 346 hours in August, yet it remains a vibrant month for outdoor activities. This trend aligns with the gradual decrease in sunlight as the year progresses, following the highest peaks from May to August, where residents bask in 336 hours to 342 hours each month. As September closes in, the sunshine still lingers warmly, setting the stage for a picturesque fall that continues to charm both locals and visitors alike.
In Monterrey, Mexico, September generally boasts a 58% chance of sunny weather, aligning closely with the patterns observed in the surrounding months. After a series of fluctuating averages throughout the summer, where July dips to a mere 45%, September marks a return to sunnier skies, reminiscent of August's sunniness. The likelihood of sun continues to hover around similar percentages in October and November, indicating a relatively stable weather trend as fall begins. This consistent sunshine not only brings warmth but also invites outdoor exploration, making September a delightful month for visitors and locals alike.
As September unfolds in Monterrey, Mexico, the city enjoys an inviting 12 hours of daylight, marking a transition from the sun-drenched summer months into the cooler embrace of fall. This slight dip in daylight from the 13 hours experienced during the peak summer months hints at the gradual shift towards shorter days. Interestingly, this consistent 12-hour duration persists through September and into October, only to further decrease as winter approaches. With this gradual waning of daylight, residents can relish the last golden rays of the warm season while anticipating the crisp, refreshing days that autumn brings.
As September ushers in a shift in Monterrey's climate, the wind begins to slow its pace, reaching an average speed of 2.0 m/s (4 mph). After a summer of stronger breezes, this drop reflects the transition into the cooler months ahead. Notably, while the wind speeds in September are reminiscent of those in January and July, the overall trend from spring to fall showcases a blend of gentle gusts around 2.5 m/s (6 mph) in late summer, leading to a gradual decrease as the year winds down. This subtle shift not only evokes a sense of calm but also marks the start of a new season, inviting residents to enjoy the serene ambiance Monterrey has to offer.
The weather in Monterrey 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 Monterrey and find detailed weather information for every month.
September and January present a striking contrast in weather patterns. In September, temperatures range from a minimum of 16°C (61°F) to a scorching maximum of 37°C (99°F), with an average of 26°C (78°F). The month is quite rainy, with 104 mm (4.1 in) of precipitation over about 10 days and a humidity level of 72%. In contrast, January experiences a much cooler climate, with temperatures dipping as low as -2°C (29°F) and peaking at 33°C (91°F), leading to an average of 14°C (58°F). Precipitation is significantly lower at 28 mm (1.1 in) over just 4 days, with humidity slightly higher at 75%. For more details on the weather in January, check out Monterrey weather in January.
September and February present vastly different weather experiences. In September, temperatures range from a minimum of 16°C (61°F) to a scorching maximum of 37°C (99°F), with an average of 26°C (78°F). This month typically sees significant rainfall, accumulating 104 mm (4.1 in) over about 10 days, accompanied by a humidity level of 72%. In contrast, February offers a much cooler climate, with temperatures dipping as low as -3°C (27°F) but averaging around 16°C (62°F), with a maximum of 35°C (95°F). Precipitation is minimal at just 20 mm (0.8 in) over about 4 days, and humidity stays relatively low at 70%. For more detailed information about the weather in February, check out Monterrey weather in February.
September and March present stark contrasts in weather patterns. In September, temperatures range significantly, with a minimum of 16°C (61°F) and a maximum soaring to 37°C (99°F), while the average temperature settles at a warm 26°C (78°F). The month also experiences substantial rainfall, totaling 104 mm (4.1 in) across 10 days, accompanied by a humidity level of 72%. In contrast, March offers a much cooler climate, featuring a minimum temperature of 3°C (38°F) and a maximum of 35°C (95°F), with an average temperature of 20°C (69°F). Precipitation in March is significantly lower, amounting to 36 mm (1.4 in) over just 7 days, and humidity rests at a more comfortable 65%. For more detailed information, check out Monterrey weather in March.
When comparing the weather in September and April, we see notable differences in temperature, precipitation, and humidity. September features a wider temperature range with minimums of 16°C (61°F) and maximums reaching as high as 37°C (99°F), while April's temperatures are cooler, ranging from a minimum of 7°C (44°F) to a maximum of 39°C (102°F). Precipitation is significantly higher in September, with 104 mm (4.1 in) over 10 days, compared to April's 48 mm (1.9 in) over just 7 days. Additionally, the humidity in September averages at 72%, making it feel a bit more oppressive than the drier, 59% humidity typically experienced in April. For more details, you can check out Monterrey weather in April.
In comparing the weather of September and May, both months exhibit similar average temperatures, hovering around 26°C (79°F). However, May tends to register slightly higher maximum temperatures, reaching up to 40°C (105°F), compared to September's peak of 37°C (99°F). Additionally, September experiences more precipitation, with 104 mm (4.1 in) over 10 rainy days, while May receives only 72 mm (2.8 in) during the same number of days. The humidity is also higher in September at 72%, compared to May's 66%. For a detailed overview, check out Monterrey weather in May.
In comparing the weather of September and June, both months experience warm temperatures, but there are some notable differences. September has a slightly lower minimum temperature of 16°C (61°F) compared to June's 18°C (65°F), while the average temperatures remain similar, with September at 26°C (78°F) and June at 27°C (81°F). June tends to reach higher maximum temperatures, peaking at 39°C (103°F), compared to September's maximum of 37°C (99°F). Additionally, September sees more precipitation at 104 mm (4.1 in) over 10 days, whereas June has less rainfall at 56 mm (2.2 in) over just 7 days. Humidity levels are comparable, with September slightly higher at 72% versus June's 71%. For a detailed look at the June weather in Monterrey, you can visit Monterrey weather in June.
When comparing the weather in September and July, a few notable differences emerge. September typically features a lower minimum temperature of 16°C (61°F) and an average of 26°C (78°F), while July has a higher minimum of 20°C (68°F) and an average of 28°C (82°F). Furthermore, September experiences more precipitation, with 104 mm (4.1 in) over approximately 10 days, compared to July's 71 mm (2.8 in) across about 6 days. Additionally, September’s humidity is significantly higher at 72%, compared to July’s more comfortable 57%. For a detailed look at July conditions, you can check Monterrey weather in July.
In comparing the weather of September to that of August, September experiences slightly cooler temperatures, with minimums around 16°C (61°F) and average highs reaching 37°C (99°F), while August starts off warmer with minimums at 20°C (68°F) and maximums at 38°C (100°F). Additionally, September is significantly wetter, recording 104 mm (4.1 in) of precipitation over 10 days, in stark contrast to August, which sees only 9 mm (0.3 in) over just 2 days. The humidity also rises in September to 72%, compared to a more comfortable 58% in August. For a detailed overview of August's conditions, you can check the Monterrey weather in August.
September in Monterrey is characterized by warmer temperatures, with a minimum of 16°C (61°F) and an average of 26°C (78°F) peaking at 37°C (99°F). It also experiences more rainfall, totaling 104 mm (4.1 in) over approximately 10 days, while humidity levels are relatively high at 72%. In contrast, October sees a notable drop in the minimum temperature to 7°C (45°F) and a decrease in the average to 22°C (72°F), with a maximum of 36°C (97°F). Precipitation also declines to 52 mm (2.0 in) over about 8 days, and humidity slightly increases to 76%. For more detailed information, you can check out Monterrey weather in October.
September and November present a striking contrast in weather patterns. In September, temperatures range from a minimum of 16°C (61°F) to a sweltering maximum of 37°C (99°F), with an average of 26°C (78°F). This month is also characterized by significant precipitation, totaling 104 mm (4.1 in) over approximately 10 days, and humidity levels sit at 72%. In contrast, November sees much cooler temperatures, with a minimum of 0°C (32°F) and a maximum of 32°C (90°F), averaging at 18°C (65°F). Rainfall is considerably less frequent, accumulating 31 mm (1.2 in) over just 6 days, though humidity rises slightly to 81%. For a more detailed look into November's climate, you can explore Monterrey weather in November.
September and December weather in Monterrey present a striking contrast. In September, temperatures can soar as high as 37°C (99°F) during the day, with an average of 26°C (78°F) and a minimum of 16°C (61°F). This month also sees significant rainfall, totaling 104 mm (4.1 in) over about 10 days, coupled with a humidity level of 72%. In contrast, December features much cooler conditions, with daytime highs reaching 33°C (92°F) and a much lower average of 16°C (61°F). The minimum temperature drops significantly to 1°C (34°F), and precipitation decreases to just 26 mm (1.0 in) over about 4 days, despite a slightly higher humidity at 80%. For more details, you can check Monterrey weather in December.
In September, Monterrey experiences a distinct shift in weather compared to other months, characterized by a warm average temperature of 26°C (78°F) and a notable increase in humidity at 72%. This month typically sees a rise in precipitation, with significant rainfall across about ten days, contributing to a total of 104 mm (4.1 in). As the summer heat begins to wane, residents and visitors alike can enjoy the transition to milder conditions, although the occasional thunderstorms are a reminder of the lingering warmth. For a deeper understanding of what to expect throughout the year, check out the details at Monterrey Climate.