September Weather in San Luis Potosi, Mexico

Last updated: April 22, 2025

In September, San Luis Potosi, Mexico experiences a dramatic range of temperatures, with highs reaching up to 49°C (121°F) and average daytime warmth around 32°C (90°F). Nighttime brings a cooler respite, dipping to a minimum of 15°C (59°F). While precipitation is minimal, with only 13 mm (0.5 in) over the course of just 2 days, the humidity remains relatively comfortable at 52%. This blend of heat and occasional rain makes September a distinctive month, highlighting the region's unique climatic character.

September Temperature in San Luis Potosi

In September, San Luis Potosi experiences a warm transition from summer to fall, with temperatures showcasing a notable range. The minimum temperature settles at a comfortable 15°C (59°F), while the average temperature rises to a sultry 32°C (90°F), making it one of the warmer months of the year. As the month progresses, daily highs can soar to a staggering 49°C (121°F), reminiscent of the peak summer heat, yet slightly tempered by the arrival of autumn breezes. This blend of warmth creates an inviting atmosphere for outdoor activities, while also hinting at the gradual cooldown that October promises. Overall, September is a month that beautifully captures the lingering summer heat while foreshadowing the delightful changes to come.

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

The chart illustrates September temperature patterns in San Luis Potosi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec596268778291969790786858
Data source: Temperature data for San Luis Potosi 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 Luis Potosi

In September, San Luis Potosi experiences a notable increase in precipitation, recording 13 mm (0.5 in) over 2 days. This uptick marks a shift from the dry summer months, where rain was scarce, with July and August bringing only 14 mm and 12 mm respectively. As the rainy season begins to wane, September's rainfall helps rejuvenate the landscape, contrasting with the preceding months of sparse moisture. This consistent pattern of late summer rains underscores the region's climatic rhythm, highlighting September as a key month for replenishing water resources before the dry spell settles in again.

September Precipitation Trends in San Luis Potosi

The chart displays monthly precipitation patterns in San Luis Potosi, 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.
JanFebMarAprMayJunJulAugSepOctNovDec91311331141213547
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in San Luis Potosi

As summer transitions to fall, September in San Luis Potosi experiences a noticeable increase in humidity, rising to 52% after the drier months of July and August, which recorded 46% and 42% respectively. This uptick marks a shift from the dry heat of mid-year, hinting at a return of moisture as the rainy season approaches its end. Historically, humidity levels in San Luis Potosi generally escalate toward the winter months, peaking at 77% in February and staying relatively high in January and December. Thus, September serves as a bridge between the arid conditions of summer and the more humid climate characteristic of the fall and winter seasons, providing a refreshing change for residents and visitors alike.

September Average Humidity in San Luis Potosi

This chart illustrates the average monthly humidity levels in San Luis Potosi, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec72%77%67%56%46%48%46%42%52%58%66%74%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in San Luis Potosi

In September, San Luis Potosi experiences a UV Index of 10, categorized as very high, which means that sun exposure can lead to skin burn in just 15 minutes. This month marks a slight decline from the peak summer months of July and August, both with an extreme index of 11. Interestingly, while the UV ratings start to lower this month, they are still significantly high compared to the earlier months of the year, such as January's moderate index of 4. As fall approaches, it's clear that sun safety remains crucial, so plan accordingly to protect your skin. For more detailed information, check out the San Luis Potosi UV Index.

Maximum UV Index Levels in San Luis Potosi for September

The chart shows the monthly maximum UV Index (UVI) for San Luis Potosi 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.
JanFebMarAprMayJunJulAugSepOctNovDec469101111121110854
Data source: San Luis Potosi 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 Luis Potosi

September brings a delightful retreat in San Luis Potosi, featuring 322 hours of sunshine that perfectly balance the summer's warmth and the autumn's approach. As the year progresses, sunlight peaks in May and June, boasting impressive hours of 373 and 377 respectively, creating a vibrant backdrop for outdoor adventures. By the time September rolls around, the days remain bright and inviting, though slightly tempered compared to the height of summer; yet, this month still outshines the cooler months ahead, where sunlight gradually decreases. This trend of diminishing daylight continues into November, bringing forth a cozy atmosphere as the sun retreats, but September retains its charm, making it an ideal time to enjoy the golden rays before the chill of winter sets in.

Monthly Sunshine Duration in San Luis Potosi: September Highlighted

The September sunshine duration represents the total number of hours San Luis Potosi 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.
JanFebMarAprMayJunJulAugSepOctNovDec204h251h309h331h373h377h375h358h322h304h264h247h
Data source: San Luis Potosi September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Luis Potosi During September

As September rolls into San Luis Potosi, residents and visitors can look forward to an impressive 85% chance of sunny weather. This marks a continuation of the region's warm and bright trend from the summer months, where August also boasts a high 83% likelihood of sunshine. Following the peak sunlit month of May at 93%, the chances remain strong into early autumn, signalling a delightful transition before October's 80% probability. Overall, September stands out as a month where the days are still glowing, perfect for outdoor activities and appreciating the region's vibrant landscapes.

Percentage of Sunny Days in September in San Luis Potosi

The chart illustrates the percentage of sunny days in San Luis Potosi 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 Luis Potosi experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec71%73%84%82%93%77%54%83%85%80%75%62%
Data source: San Luis Potosi September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Luis Potosi in September

In September, San Luis Potosí enjoys approximately 12 hours of daylight, marking a subtle transition as summer fades into autumn. This month heralds a slight reduction in daylight from the longer, sun-soaked days of June and July, which peak at 14 hours. As the year progresses, the daylight gradually shortens, a trend that begins in late summer and continues into the winter months. By October, daylight recedes to 11 hours, creating a rhythm of light that dances with the seasons, reminding residents of nature's cyclical beauty. Overall, September offers a perfect balance—enough daylight to savor the last warm days while hinting at the cooler months ahead.

Average Daylight Hours in San Luis Potosi for September

The chart illustrates the variation in daylight duration in San Luis Potosi throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 16m11h 2m12h12h 59m13h 49m14h 14m14h13h 16m12h 18m11h 19m10h 28m10h 2m
Data source: San Luis Potosi daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in San Luis Potosi

In September, San Luis Potosí experiences a gentle lull in wind activity, with an average speed of 2.1 m/s (5 mph). This marks a subtle decline from the summer months, where winds were slightly stronger, peaking at 2.9 m/s (6 mph) in July. Notably, September's breezes are among the lightest of the year, echoing the calm before the seasonal shifts that October and November bring. As the winds soften, the atmosphere becomes ideal for embracing the warm, early autumn days, inviting outdoor activities and a deeper connection with the vibrant surroundings. This month serves as a delightful transition, where nature’s whispers prepare San Luis Potosí for the cooling embrace of fall.

Average September Wind Speed in San Luis Potosi

The chart displays monthly wind speed patterns in San Luis Potosi, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.42.72.72.72.52.52.92.52.1 m/s2.42.22.2
Data source: San Luis Potosi September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in San Luis Potosi Compares to Other Months

The weather in San Luis Potosi 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 San Luis Potosi and find detailed weather information for every month.

September and January present strikingly contrasting weather conditions. In September, temperatures soar with an average high of 32°C (90°F) and can reach an extreme of 49°C (121°F), while the humidity sits at a moderate 52%. Conversely, January brings much cooler temperatures, peaking at an average of 15°C (60°F) with a maximum of 30°C (86°F) and a minimum of just 1°C (35°F). Additionally, January is marked by higher humidity levels at 72%, although it experiences slightly less precipitation, averaging 9 mm over just one day, compared to September’s 13 mm over two days. For more detailed insights, check this link: San Luis Potosi weather in January.

September and February in San Luis Potosi offer contrasting weather experiences. September experiences warmer temperatures, with a minimum of 15°C (59°F) and a scorching maximum of 49°C (121°F), while February is much cooler, starting at a minimum of 2°C (35°F) and peaking at 31°C (89°F). Both months see similar precipitation levels, with 13 mm (0.5 in) in September and 12 mm (0.5 in) in February, each with roughly two rainy days. However, February tends to be more humid at 77%, compared to September's 52%. For a detailed look at February's weather, you can visit San Luis Potosi weather in February.

September and March present notably different weather conditions. In September, temperatures soar, with an average of 32°C (90°F) and maximums reaching an intense 49°C (121°F), while humidity remains around 52%. Precipitation is minimal, with only 13 mm (0.5 in) spread over just 2 days. In contrast, March offers a much milder climate, with an average temperature of 20°C (68°F) and maximums peaking at 37°C (99°F). Humidity increases to 67%, and precipitation is slightly lower, at 11 mm (0.4 in) over just 1 day. For a deeper dive into the March climate, visit San Luis Potosi weather in March.

When comparing the weather between September and April, distinct differences emerge in temperature and precipitation levels. September features a much higher average temperature, peaking at 32°C (90°F), with maximums reaching a scorching 49°C (121°F), while April presents a milder climate, with an average temperature of 25°C (77°F) and a maximum of 43°C (110°F). Precipitation is relatively minimal in both months; however, September sees slightly more rain with 13 mm (0.5 in) over 2 days, compared to April's scarce 3 mm (0.1 in) without any rainy days. Additionally, humidity levels are somewhat comparable, with September at 52% and April slightly higher at 56%. For a detailed overview of April weather in this region, check San Luis Potosi weather in April.

In September, the weather tends to be hotter and slightly more humid compared to May. Average temperatures reach up to 32°C (90°F), with maximums soaring to 49°C (121°F), while the minimum dips to 15°C (59°F). In contrast, May has a milder climate, with an average temperature of 28°C (82°F) and a maximum of 44°C (111°F), alongside lower humidity at 46%. Additionally, September experiences some rainfall with 13 mm (0.5 in) over two days, whereas May remains dry with only 3 mm (0.1 in) and no recorded rainy days. For further details, you can check out the full overview of San Luis Potosi weather in May.

In comparing the weather of September and June, both months experience high maximum temperatures reaching up to 49°C (121°F). However, September tends to be slightly cooler overall, with average temperatures of 32°C (90°F) compared to June's average of 33°C (91°F). Moreover, September sees a bit more precipitation, with 13 mm falling over 2 days, while June is exceptionally dry, recording just 1 mm with no rainy days at all. Humidity levels are also marginally higher in September at 52%, compared to 48% in June. For more detailed weather information, you can check out San Luis Potosi weather in June.

In comparing the weather of September and July, it's clear that both months experience high temperatures, but July typically feels hotter overall. With an average temperature of 36°C (97°F) and a minimum of 22°C (72°F), July has a higher average than September, which averages 32°C (90°F) and starts at a cooler minimum of 15°C (59°F). Additionally, July's maximum temperature of 48°C (119°F) is closely competitive with September's peak of 49°C (121°F). Precipitation levels are similar in both months, with July receiving 14 mm (0.5 in) over 3 days, while September experiences slightly less at 13 mm (0.5 in) over 2 days. Humidity also plays a role, as September is more humid at 52% compared to July's 46%. For more detailed information on July's weather, check out San Luis Potosi weather in July.

In September, the weather is slightly more moderate compared to August, with minimum temperatures of 15°C (59°F), an average of 32°C (90°F), and a maximum of 49°C (121°F). While precipitation remains low at 13 mm (0.5 in), it is notable that it only rains for about 2 days. The humidity level is around 52%, which is higher than in August.

In contrast, August experiences warmer conditions with minimum temperatures at 24°C (76°F), an average high of 36°C (97°F), and a peak of 48°C (118°F). It also has a similar amount of rainfall at 12 mm (0.5 in), but this occurs over 4 days, leading to lower humidity at 42%. For more details, you can check San Luis Potosi weather in August.

In September, the weather is substantially warmer, with average temperatures reaching up to 32°C (90°F) and maximums soaring to 49°C (121°F). The month sees a bit more precipitation, totaling 13 mm (0.5 in) over two days, and has a humidity level of 52%. In contrast, October brings a cooler and more pleasant climate, with an average temperature of 26°C (79°F) and a maximum of 43°C (110°F). Precipitation is significantly lower at just 5 mm (0.2 in) over no rainy days, and the humidity rises slightly to 58%. Overall, October offers a much more temperate weather experience compared to the sweltering heat of September. For more detailed information, you can check the San Luis Potosi weather in October.

In September, the weather is typically hot, with temperatures ranging from a minimum of 15°C (59°F) to an average of 32°C (90°F) and reaching as high as 49°C (121°F). Precipitation is minimal, averaging just 13 mm (0.5 in) over about 2 days, and the humidity is relatively moderate at 52%. In contrast, November brings much cooler conditions, with temperatures dropping to a minimum of 7°C (44°F) and averaging 20°C (68°F), peaking at 35°C (96°F). Rain is rare in November, with only 4 mm (0.1 in) of precipitation recorded across 0 days, while humidity increases to 66%. For more details about November weather, you can visit San Luis Potosi weather in November.

In September, the weather is characterized by notably high temperatures, with averages reaching 32°C (90°F) and maximums soaring up to 49°C (121°F). The humidity levels are relatively moderate at 52%, and there is minimal precipitation, with just 13 mm (0.5 in) over two days. In contrast, December brings a significant drop in temperatures, with averages around 14°C (58°F) and maximums of 29°C (84°F). The humidity rises to 74%, creating a cooler and more humid atmosphere, while precipitation decreases to 7 mm (0.3 in) over just one day. For more detailed information, you can check San Luis Potosi weather in December.

Compare San Luis Potosi's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in San Luis Potosi

As September rolls in, San Luis Potosi experiences a significant shift in weather dynamics compared to the scorching summer months. With temperatures averaging around 32°C (90°F), the heat is still palpable, but the month brings a gradual decrease from the peaks of summer, making outdoor activities more enjoyable. While the minimum temperatures drop to a refreshing 15°C (59°F) at night, the humidity remains moderate at 52%, providing a slight relief from the arid conditions. This month also introduces sporadic rainfall, with just a couple of days of precipitation totaling 13 mm (0.5 in), signaling a transition toward the wetter season. For a deeper understanding of how the weather in San Luis Potosi evolves throughout the year, check out the detailed insights on San Luis Potosi Climate.