Last updated: April 22, 2025
September in La Union, Mexico showcases a vibrant yet humid climate, with temperatures peaking at a scorching 38°C (100°F) and averaging a comfortable 28°C (82°F). While nighttime brings relief with lows around 22°C (72°F), the month is characterized by significant precipitation, accumulating 154 mm (6.1 in) over 26 days. Humidity levels hover around a sticky 82%, making it a month where visitors can expect frequent showers interspersed with warm weather, perfect for those who enjoy the lush greenery that follows the rains.
In September, La Union warms up as summer begins to wane, showcasing a minimum temperature of 22°C (72°F) and an average of 28°C (82°F), making it quite pleasant. With a maximum temperature reaching up to 38°C (100°F), it’s one of the warmer months of the year, aligning closely with the heat of August. This month signals a slight continuation of the humid warmth, glimpsing a shift from the hotter summer days towards the cooler fall temperatures that will arrive in October. Travelers can expect balmy evenings and sunny days, perfect for enjoying the stunning coastal landscapes.
September marks a significant peak in precipitation for La Union, Mexico, as the region experiences an average of 154 mm (6.1 in) of rainfall over 26 days. This surge is part of a broader trend, where the summer months lead up to this rainy crescendo, with June seeing a substantial 227 mm followed by robust figures in July and August. The consistent rainfall throughout these months highlights the monsoon influence in the region, culminating in September's heavy downpours. As autumn approaches, October continues this trend but typically with slightly less intensity, reminding residents of the seasonal shifts that define La Union's climate.
In September, La Union experiences a noticeable uptick in humidity, reaching 82%, just shy of the levels seen in the colder months. This shift marks a significant increase from the 73% humidity in August, signaling the gradual transition into the more humid fall season. Over the course of the year, humidity levels in La Union generally decline from a high of 85% in January to a low of 62% in April and May, before gradually rising again as the year progresses. As September approaches, the air becomes significantly more humid, foreshadowing the even higher humidity levels of October and November, which often hover around 86% and 87%, respectively. This trend highlights the region's dynamic climate, making it essential for residents and visitors alike to prepare for the lush and moist environment typical of this time of year.
In September, La Union experiences a UV Index of 13, maintaining the extreme exposure category that has dominated the summer months. This level signifies a continued need for protective measures, as the burn time remains a quick 10 minutes. Overall, the UV Index trends from January to September display a pattern of intensifying sun exposure, peaking at 14 in April before slightly tapering in the fall. As the region transitions into autumn, it's crucial to remain vigilant about sun safety under these consistently high levels. For more detailed insights into the UV Index throughout the year, visit La Union UV Index.
UV Risk Categories
September in La Union, Mexico, continues the beautiful trend of abundant sunshine, boasting 288 hours of glorious sunlight. Following the peak of 325 hours in May, the summer months have consistently offered impressive hours of daylight, with August trailing closely behind at 316 hours. As summer gently transitions into fall, September maintains a healthy brightness that precedes the cooler months ahead, as October and November both settle back to 270 hours. This gradual decline reminds visitors of the natural rhythm of the seasons, making September a delightful time to bask in La Union's warm sun before the days grow shorter.
In La Union, Mexico, the likelihood of sunny weather in September stands at a modest 33%, reflecting a trend of fluctuating sunshine throughout the year. Following the vibrant sunshine of March and the warmer months leading up to August, September enters a transitional phase where the chance of sunshine dips slightly. This decrease can be observed as the region shifts from the peak summer season, characterized by higher probabilities of clear skies, into the cooler fall months. With October offering a slight upturn in sunny prospects at 41%, September presents a mix of sun and clouds, catering to those who appreciate the gentle ebb and flow of seasonal changes.
In La Union, Mexico, September marks a seamless transition in daylight duration, offering approximately 12 hours of sunlight each day. This month reflects a continued trend seen since the summer, where daylight peaks at 13 hours in June and July before gently tapering off. Following a slight decline in August, the consistent 12-hour rhythm of September has a warm reassurance that welcomes the onset of autumn. As the year progresses into October, daylight begins to diminish again, settling into the shorter days characteristic of winter. This cyclical pattern not only enhances the beauty of the region but also invites both locals and visitors to bask in the golden hues of early fall.
In September, La Union, Mexico, experiences a subtle decline in wind speed, averaging 2.3 m/s (5 mph), mirroring the calmness of August. This consistent trend of gentle breezes marks the culmination of the summer months, as the winds gradually shift. Prior to September, winds steadily increased from January's modest 2.3 m/s to a peak in May at 3.2 m/s (7 mph). As autumn approaches, the winds hush, leading into a quieter season with October and November showing further decreases. This gentle rhythm of the wind shapes the coastal experience, inviting locals and visitors alike to savor the tranquil atmosphere of La Union as summer wanes.
The weather in La Union 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 La Union and find detailed weather information for every month.
September and January present contrasting weather patterns. In September, temperatures range from a minimum of 22°C (72°F) to a scorching maximum of 38°C (100°F), with an average of 28°C (82°F). The month is also marked by high humidity at 82% and significant rainfall, totaling 154 mm (6.1 in) over 26 days. In contrast, January enjoys a milder climate, featuring a minimum temperature of 14°C (57°F) and an average of 24°C (75°F), peaking at 37°C (99°F). Rainfall is substantially lower in January, with only 43 mm (1.7 in) falling over 11 days and humidity slightly elevated at 85%. For a more detailed look at January weather, you can check this link: La Union weather in January.
September and February exhibit striking contrasts in weather patterns. In September, temperatures can reach a sweltering maximum of 38°C (100°F), with an average of 28°C (82°F) and high humidity levels at 82%. This month also experiences significant rainfall, with 154 mm (6.1 in) spread over 26 days. In contrast, February offers a more temperate climate, featuring a pleasant average of 25°C (78°F) and a maximum of 36°C (98°F). Additionally, February sees considerably less rain, accumulating only 29 mm (1.2 in) over just 10 days, while humidity remains slightly lower at 78%. For a detailed look at the weather trends, check out La Union weather in February.
September is characterized by significantly warmer temperatures, with an average of 28°C (82°F) and highs reaching up to 38°C (100°F), while March has milder temperatures with an average of 26°C (80°F) and maximums of 36°C (98°F). In terms of precipitation, September is much wetter, experiencing 154 mm (6.1 in) over 26 days, compared to just 23 mm (0.9 in) over 7 days in March. This is compounded by higher humidity levels in September at 82%, compared to 67% in March, making the latter feel more comfortable. For more detailed weather-specific insights, check out La Union weather in March.
When comparing the weather in September and April, notable differences emerge. September typically experiences warmer nights with a minimum temperature of 22°C (72°F) compared to April's milder 17°C (63°F). Despite both months averaging around 28°C (82°F), April can see exceptionally high temperatures peaking at 41°C (107°F), while September's maximum reaches 38°C (100°F). Precipitation is another significant contrast; September is characterized by much heavier rainfall, accumulating 154 mm (6.1 in) over 26 days, whereas April enjoys only 46 mm (1.8 in) over just 7 days. Additionally, April's humidity is lower at 62%, compared to the high humidity level of 82% in September. For more detailed insights, check out La Union weather in April.
September and May present distinct weather patterns. In September, temperatures range from a minimum of 22°C (72°F) to a maximum of 38°C (100°F), with an average temperature of 28°C (82°F). The month is characterized by high humidity at 82% and frequent rain, totaling 154 mm (6.1 in) over 26 days. In contrast, May experiences slightly cooler temperatures, with a minimum of 19°C (67°F) and a peak of 39°C (103°F), averaging 29°C (85°F). This month sees significantly less precipitation, with only 75 mm (3.0 in) over 18 days and lower humidity at 62%. For more details on May's weather, visit La Union weather in May.
In comparing the weather between September and June, both months experience similar temperature ranges, with minimum temperatures around 22°C (72°F) and maximums peaking at 38°C (100°F for September and 101°F for June). However, September is marked by higher humidity levels at 82%, compared to June's 63%, making September feel more humid and oppressive. Additionally, September receives more precipitation, accumulating 154 mm (6.1 in) over 26 days, in contrast to June's 227 mm (8.9 in) over 25 days. For more detailed insights into June weather, you can refer to La Union weather in June.
September weather tends to be slightly warmer than July, with average temperatures reaching 28°C (82°F) in both months, but September sees a higher maximum temperature of 38°C (100°F) compared to July's 37°C (98°F). Rainfall is more significant in September, with 154 mm (6.1 in) occurring over 26 days, whereas July experiences 113 mm (4.4 in) spread across 23 days. Additionally, the humidity levels in September are notably higher at 82%, compared to 66% in July, making September feel stickier and more uncomfortable. For a more detailed look at July weather, check out La Union weather in July.
In comparing the weather of September and August, September presents slightly warmer temperatures, with a minimum of 22°C (72°F) and a maximum of 38°C (100°F), compared to August's 21°C (70°F) minimum and 37°C (99°F) maximum. Both months average around 28°C (82°F in September and 83°F in August), indicating a similar overall warmth. However, September is notably more humid at 82%, while August has a humidity level of 73%. Precipitation is also higher in September, with 154 mm (6.1 in) over 26 days, compared to August's 125 mm (4.9 in) over 24 days. For more details on the weather in August, you can check La Union weather in August.
In September, the weather is typically warm, with minimum temperatures around 22°C (72°F) and averages reaching 28°C (82°F), peaking at 38°C (100°F). This month experiences frequent rainfall, with 154 mm (6.1 in) of precipitation spread over 26 days and an average humidity of 82%. In contrast, October sees slightly cooler temperatures, with minimums of 18°C (64°F) and an average of 27°C (80°F), while the maximum temperature decreases to 36°C (97°F). However, October also sees a higher total precipitation of 180 mm (7.1 in) over 24 days, accompanied by increased humidity at 86%. For more detailed insights on the weather, check La Union weather in October.
The weather in September is notably warmer than in November, with average temperatures reaching 28°C (82°F) compared to November's 25°C (77°F). September experiences higher maximum temperatures, peaking at 38°C (100°F), while November's maximum is a milder 33°C (92°F). Additionally, September sees significantly more rainfall, totaling 154 mm (6.1 in) over 26 days, which is higher than November's 73 mm (2.9 in) across 15 days, making November a drier month overall. Humidity remains high in both months, with November slightly more humid at 87%, compared to September's 82%. For more detailed information, check La Union weather in November.
September weather is characterized by much warmer temperatures, with minimums around 22°C (72°F) and maximums soaring to 38°C (100°F). The month experiences considerable rainfall, totaling 154 mm (6.1 in) over 26 days, and humidity levels remain high at 82%. In contrast, December offers a more mild climate, with a minimum temperature of 12°C (53°F) and a maximum of 33°C (92°F), as well as significantly less precipitation at 46 mm (1.8 in) over just 14 days. Humidity rises slightly to 87%, creating a crisp but still relatively humid atmosphere. For more detailed information, you can check La Union weather in December.
As September rolls in, La Union experiences a notable shift in weather patterns, marked by a blend of warmth and humidity. While daytime temperatures reach a peak that can feel quite intense, the prevailing average offers a more comfortable heat. This month also brings increased moisture, with frequent rain showers gracing the landscape on many days, resulting in a lush environment that differs from the drier spells of other months. With humidity levels soaring, the air feels particularly thick, contrasting starkly with the dry heat of the preceding summer months. Such conditions evoke a vibrant transformation in the region, making it a unique time to experience the beauty of La Union. For more detailed insights into the weather patterns throughout the year, visit La Union Climate.