Last updated: April 22, 2025
Experience the vibrant September weather of Monterrey, Mexico, where temperatures can soar to a maximum of 37°C (99°F), coupled with an average of 25°C (76°F). Early fall welcomes the occasional cooling breeze, with minimum temperatures dipping to 15°C (60°F). While the month sees 61 mm (2.4 in) of precipitation across 9 days, the high humidity of 82% adds a touch of tropical flair to the region. Embrace the mix of warmth and refreshing rainfall that defines Monterrey’s September, making it a unique time to explore the city's charm.
In September, Monterrey experiences a transition from the sweltering summer months to more moderate temperatures. With daytime highs peaking at 37°C (99°F) and average temperatures settling around 25°C (76°F), visitors can expect warm and pleasant conditions. The evenings bring a gentle respite, with nightly lows of 15°C (60°F), making it a comfortable time for outdoor activities. Compared to the preceding months, September maintains much of the summer warmth while hinting at the cooler temperatures that follow in October. This month serves as a sweet spot, where the heat is balanced with the approaching fall, creating an inviting atmosphere for those exploring Monterrey's rich culture and vibrant landscape.
In Monterrey, Mexico, September stands out as a significant month for precipitation, marking the transition into the more temperate autumn season. With 61 mm (2.4 in) of rain spread over 9 days, it is the wettest month of the year, following the gradually increasing trend established in the summer months. The rainfall in September is markedly higher than that of the preceding months, particularly compared to August's 32 mm (1.2 in) and July's 49 mm (1.9 in). This uptick not only signifies the end of the arid summer but also refreshes the landscape, setting the stage for the invigorating cooler months ahead. As the city welcomes the rains, September becomes a vital time for replenishing local ecosystems, underscoring the importance of this month in Monterrey's climatic rhythm.
As summer gives way to fall, September in Monterrey, Mexico marks a noticeable uptick in humidity, rising to a notably high 82%. This increase reflects a trend observed throughout the year, where the earlier months exhibit lower humidity levels—peaking in the warmth of July and August at 73% and 71% respectively. However, September signals the transition into the wetter season, leading into the autumn months where humidity levels remain high, reaching 83% in October and stabilizing around 82% in November. This shift not only impacts the atmosphere but also influences daily life in Monterrey, making it a month of palpable moisture in the air and a lush, vibrant environment.
As September rolls into Monterrey, Mexico, residents and visitors can expect the UV Index to hold steady at 13, placing it firmly in the extreme exposure category. This trend of elevated UV levels has been consistent since June, reflecting a significant period of high sun intensity that began in the earlier summer months. With a burn time of just 10 minutes, it’s essential to take precautions during this time. Keeping skin protected from the intense rays and seeking shade during peak hours is crucial to avoid harmful effects. As autumn approaches, the UV Index will begin to decline, with October forecasted at 11; however, awareness and protection remain key during September. To stay informed about daily changes in the UV Index, visit Monterrey UV Index.
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As summer fades into fall, September in Monterrey, Mexico, continues to bask in the warmth of abundant sunshine, boasting an impressive 294 hours of bright rays. This month is marked by a gentle decline from the peak of 357 hours in July, yet remains significantly brighter than the dreary winter months ahead. Following the vibrant summer, where June and August shine with nearly identical luminescence, September offers a delightful transition, captivating residents and visitors alike with its lingering warmth. The trend of decreasing sunlight continues through the fall, leading into the cool embrace of October, which sits at 285 hours, a reminder of the vibrant summers that linger just past.
In Monterrey, Mexico, September marks a transitional point in the city's weather patterns. As summer fades, the likelihood of sunny days drops to a moderate 52%, reflecting the shift towards the cooler and cloudier months ahead. This is a notable decline from the peak sunshine months of May and early summer, where the chance of sun reaches upwards of 76%. Interestingly, September sits close to the end of August's 49%, signaling that while the days may be shorter and more unpredictable, there’s still a fair chance to experience the sun's warmth. As you plan your September activities, embrace the blend of cusp-season charm—where the remnants of summer collide with the promise of autumn.
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 unfolds in Monterrey, Mexico, the winds begin to pick up slightly, averaging 2.1 m/s (5 mph), offering a gentle breath of fresh air amidst the lingering summer warmth. This increase marks a subtle yet noticeable shift from the lighter breezes of the preceding months, such as July and August, which both registered at 1.8 m/s (4 mph) and 1.9 m/s (4 mph) respectively. With this moderate breeze, September strikes a harmonious balance, providing just enough wind to invigorate the landscape without overwhelming the senses. As the falling leaves signal the transition toward autumn, this month represents a pivotal moment where the weather begins its gradual evolution, paving the way for the cooler temperatures of the upcoming months.
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 strikingly different weather conditions. In September, temperatures range from a cool 15°C (60°F) to a scorching 37°C (99°F), with an average of 25°C (76°F). This month also sees significant precipitation, with around 61 mm (2.4 inches) over 9 rainy days, coupled with a high humidity level of 82%. In contrast, January offers a much cooler climate, with temperatures dipping as low as -1°C (30°F) and peaking at 30°C (86°F), averaging at 15°C (59°F). Notably, January is characterized by very little precipitation, receiving only 6 mm (0.2 inches) over no rainy days, and a lower humidity level of 70%. For more detailed information, you can check Monterrey weather in January.
September and February present distinctly different weather patterns. In September, temperatures range from a minimum of 15°C (60°F) to a maximum of 37°C (99°F), with an average temperature of 25°C (76°F). This month sees significant precipitation, averaging 61 mm (2.4 inches) over about 9 days, and high humidity at 82%. Conversely, February features much cooler conditions, with temperatures ranging from 0°C (31°F) to 35°C (96°F), and an average of 18°C (65°F). Precipitation is minimal, at only 6 mm (0.2 inches) over just 1 day, and humidity lowers to 62%. For a more detailed look at weather in February, check out Monterrey weather in February.
September and March display distinctly different weather patterns. In September, temperatures range from a minimum of 15°C (60°F) to a maximum of 37°C (99°F), with an average of 25°C (76°F). The month sees substantial precipitation, totaling 61 mm (2.4 in) over 9 days, and high humidity at 82%. In contrast, March experiences milder temperatures, with a minimum of 5°C (42°F) and a maximum of 38°C (101°F), averaging 21°C (71°F). Precipitation is minimal in March, accumulating only 9 mm (0.3 in) over just 1 day, and humidity is lower at 53%. For a more detailed look at March weather, visit Monterrey weather in March.
In September, the weather in Monterrey is characterized by higher humidity levels at 82%, with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 37°C (99°F). This month also experiences significantly more rainfall, totaling 61 mm (2.4 in) over approximately 9 days. In contrast, April offers a milder climate, with lower humidity at 48% and temperatures from a minimum of 9°C (49°F) to the same peak of 37°C (99°F). Precipitation is scarce during this month, with only 3 mm (0.1 in) recorded over just 1 day. For more detailed information, you can visit Monterrey weather in April.
When comparing the weather in September and May, there are notable differences in temperature and precipitation. September experiences a minimum temperature of 15°C (60°F) and can peak at 37°C (99°F), with an average of 25°C (76°F) and significant humidity at 82%. The month also sees about 61 mm (2.4 in) of precipitation over 9 days. In contrast, May tends to be hotter, with average temperatures sitting around 28°C (82°F) but can reach a maximum of 40°C (104°F). In May, precipitation is much lower, with only 7 mm (0.3 in) recorded over just a single day and humidity at a more comfortable 52%. For more details about the weather in May, you can check Monterrey weather in May.
In comparing the weather of September and June, September offers a more moderate temperature range, with a minimum of 15°C (60°F), an average of 25°C (76°F), and a maximum of 37°C (99°F). In contrast, June is typically hotter, with a minimum temperature of 15°C (59°F), an average of 28°C (83°F), and a peak of 40°C (104°F). Precipitation levels also differ significantly; September sees 61 mm (2.4 in) of rain over 9 days, while June only experiences 24 mm (0.9 in) over just 4 days, resulting in higher humidity in September at 82% compared to June's 64%. For more details about June weather, you can visit Monterrey weather in June.
September and July present somewhat similar temperature ranges, with both months reaching highs of 37°C (99°F). However, September tends to be slightly cooler on average, with temperatures ranging from a minimum of 15°C (60°F) to an average of 25°C (76°F), while July has a higher minimum of 18°C (65°F) and an average temperature of 27°C (81°F). In terms of precipitation, September receives more rain—with 61 mm (2.4 in) over 9 days—compared to July's 49 mm (1.9 in) over 8 days. Additionally, September experiences higher humidity at 82%, contrasting with July's more moderate level of 73%. For more detailed insights into the weather during July, you can refer to Monterrey weather in July.
In comparing the weather between August and September, we see notable differences in temperature and precipitation patterns. September averages a slightly lower minimum temperature at 15°C (60°F) compared to August's 16°C (61°F), while the average maximum temperature in September reaches 37°C (99°F), just above August's max of 36°C (97°F). However, September is marked by increased humidity at 82%, up from August's 71%. Additionally, September experiences more rainfall, with a total of 61 mm (2.4 in) spread over 9 days, compared to August's 32 mm (1.2 in) over 5 days. For a detailed look at August weather, visit Monterrey weather in August.
In September, temperatures begin to cool down slightly with a minimum of 15°C (60°F) and an average high of 37°C (99°F), while still experiencing significant warmth. The month sees about 61 mm (2.4 in) of precipitation over 9 days, along with high humidity at 82%. In contrast, October brings a more pronounced drop in temperature with a minimum of 8°C (47°F) and an average high of 36°C (97°F), offering a comfortable climate for outdoor activities. Precipitation decreases to 37 mm (1.4 in) over just 5 days, and humidity remains high at 83%. For more detailed insights, you can check Monterrey weather in October.
September showcases a much warmer climate compared to November, with temperatures ranging from a minimum of 15°C (60°F) to a scorching maximum of 37°C (99°F), and an average of 25°C (76°F). The month sees considerable precipitation, totaling 61 mm (2.4 in) over 9 days, alongside a high humidity level of 82%. In contrast, November brings a significant drop in temperatures, featuring a minimum of -2°C (28°F) and a maximum of 33°C (91°F), with an average temperature of 19°C (66°F). This month also experiences markedly less precipitation, with only 6 mm (0.2 in) occurring over just 1 day, while maintaining the same humidity level of 82%. For more details on November weather, check out Monterrey weather in November.
In September, temperatures in Monterrey typically range from a minimum of 15°C (60°F) to a scorching maximum of 37°C (99°F), with an average of 25°C (76°F). This month also brings significant precipitation, with about 61 mm (2.4 in) falling over an average of 9 days, accompanied by high humidity levels of 82%. In contrast, December experiences much cooler conditions, with temperatures dipping as low as -2°C (28°F) at night and averaging around 15°C (60°F) during the day, reaching a maximum of 30°C (87°F). Precipitation in December is notably lower, totaling only 13 mm (0.5 in) over just 2 days, while humidity remains slightly elevated at 84%. For more details, visit Monterrey weather in December.
As September unfolds in Monterrey, it marks a transition from the sweltering heat of summer to a more temperate climate. The average temperature presents a comfortable balance, yet the highs can still reach up to a sizzling 37°C (99°F). This month also brings an increase in humidity, creating a vibrant, tropical feel, coupled with occasional rains that result in about nine days of precipitation. Compared to the drier, hotter months preceding it, September serves as a refreshing pause, gently ushering in the autumn season. For a deeper dive into the region's weather nuances, explore Monterrey Climate.