September Weather in Saint Joseph, United States

Last updated: February 24, 2025

In September, Saint Joseph experiences a delightful transition into fall, with daytime temperatures peaking at 32°C (90°F) and averaging around 20°C (68°F). Nights bring a refreshing coolness, dipping to a minimum of 6°C (43°F). The month is somewhat damp, recording 73 mm (2.9 in) of rainfall over 8 days, contributing to a humidity level of 78%. This blend of warm days and cool nights, coupled with periodic rain, paints a picturesque and inviting atmosphere, perfect for outdoor activities and enjoying the changing seasons.

September Temperature in Saint Joseph

September in Saint Joseph, United States, marks a delightful transition into autumn, characterized by mild temperatures that invite outdoor activities. With minimum temperatures hovering around 6°C (43°F) and an average reaching a comfortable 20°C (68°F), it’s a month where the heat of summer begins to wane. The maximum temperature can still peak at a toasty 32°C (90°F), offering a final chance to enjoy warmer days before the chill sets in. This gradual shift from the summer warmth to cooler days provides a refreshing backdrop for vibrant fall foliage, making September a lovely time to explore the area's natural beauty.

September Weather in Saint Joseph: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Saint Joseph, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec282938465869747367554135
Data source: Temperature data for Saint Joseph 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 Saint Joseph

In September, Saint Joseph experiences a lull in rainfall, mirroring the drier pattern established in August, with just 73 mm (2.9 in) of precipitation over 8 days. This decline marks a notable contrast to the wetter month of May, where the city received a substantial 168 mm (6.6 in), and April, with 108 mm (4.2 in). As summer transitions into fall, the change in both precipitation amount and frequency signals a gradual shift in weather patterns, setting the stage for the wetter months ahead, especially October, which typically sees an uptick in rainfall. The overall decrease in precipitation days during September hints at a delightful interlude of milder weather, inviting residents to enjoy the onset of autumn's crisp air.

September Precipitation Trends in Saint Joseph

The chart displays monthly precipitation patterns in Saint Joseph, 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.
JanFebMarAprMayJunJulAugSepOctNovDec7976871081681339473731457469
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Saint Joseph

In September, the humidity in Saint Joseph, United States, dips to 78%, marking a shift towards the drier conditions of fall. This decrease continues a gradual trend observed through the summer months, where humidity levels steadily declined from 81% in July and 79% in August. Despite this seasonal reduction, September's levels remain comfortably lower than the high points experienced earlier in the year, such as 87% in April and a notable 89% in November. As autumn approaches, residents and visitors alike can enjoy the crisp air without the stifling humidity of the peak summer months.

September Average Humidity in Saint Joseph

This chart illustrates the average monthly humidity levels in Saint Joseph, 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.
JanFebMarAprMayJunJulAugSepOctNovDec85%85%86%87%81%82%81%79%78%81%89%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Saint Joseph

As summer transitions into early autumn, September in Saint Joseph continues to see a notable UV Index of 8, categorizing it as very high. This slight dip from the peak summer months reflects a decrease in burn time to just 15 minutes, urging residents and visitors to stay vigilant about sun protection. Notably, September maintains a consistently high index, mirroring the trends established in July and August, emphasizing the lingering intensity of UV radiation even as the season changes. As we move from the summer heat into fall, it remains crucial to prioritize skin safety, especially with the UV Index still registering at elevated levels. For more insights, visit Saint Joseph UV Index.

Maximum UV Index Levels in Saint Joseph for September

The chart shows the monthly maximum UV Index (UVI) for Saint Joseph 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.
JanFebMarAprMayJunJulAugSepOctNovDec34689101098642
Data source: Saint Joseph 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 Saint Joseph

As summer gives way to fall in Saint Joseph, September retains a generous slice of the season's warmth, boasting 288 sunshine hours that illuminate the transition. Following a peak in July with 358 hours, the sunlight begins to wane, yet September holds onto the brightness better than most months. This makes it a delightful period for outdoor activities, as the sun remains prevalent while temperatures begin to cool. The gradual decrease in daylight from the summer months, notably down from August's 341 hours, signals the onset of autumn's charm, allowing residents and visitors alike to revel in the beautiful tapestry of changing leaves under golden rays of sunshine.

Monthly Sunshine Duration in Saint Joseph: September Highlighted

The September sunshine duration represents the total number of hours Saint Joseph 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.
JanFebMarAprMayJunJulAugSepOctNovDec94h157h235h245h293h331h358h341h288h218h167h148h
Data source: Saint Joseph September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Saint Joseph During September

As summer fades into autumn, September in Saint Joseph, United States, offers a delightful change in weather patterns, boasting a 56% chance of sunny days. This marked increase establishes September as one of the sunniest months of the year, surpassing the peak summer months of July and August, which hover around 46% and 48%, respectively. It's a refreshing shift from the gloomier winter months, where the likelihood of sunshine dips to 18% in January and only 20% in February. With each passing month, the chances of enjoying sunny weather tend to rise during the spring and summer, culminating in the invite of September sunshine that heralds the approach of cooler days ahead. Perfect for outdoor activities, this month showcases the sunny charm that Saint Joseph brings to its residents and visitors alike.

Percentage of Sunny Days in September in Saint Joseph

The chart illustrates the percentage of sunny days in Saint Joseph 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 Saint Joseph experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec18%20%48%42%37%44%46%48%56%32%33%28%
Data source: Saint Joseph September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Saint Joseph in September

As September unfolds in Saint Joseph, the days begin to shorten, transitioning from the vibrant peak of summer. With an average of 12 hours of daylight, this month marks the gradual shift towards the cooler autumn months. Following the lush brightness of July and August, which boasted 14 and 13 hours respectively, September sees a gentle decline in daylight, setting the stage for the crispness of October, which offers just 11 hours. This pattern reveals a clear trend: from the 15 hours enjoyed in June, daylight steadily decreases, as nature prepares for the winter months ahead. The changing light serves as a reminder of the cyclical dance of seasons, inviting residents to savor the softer, golden hues of early fall.

Average Daylight Hours in Saint Joseph for September

The chart illustrates the variation in daylight duration in Saint Joseph throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 30m10h 35m11h 58m13h 22m14h 34m15h 9m14h 50m13h 46m12h 25m11h 1m9h 47m9h 10m
Data source: Saint Joseph daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Saint Joseph

As September rolls into Saint Joseph, the wind begins to pick up from the summer lull, with an average speed of 4.3 m/s (10 mph), signaling a shift towards the breezier months ahead. This gentle increase from the more calm summer days, where winds dipped to a low of 3.0 m/s (7 mph) in August, shows a gradual transition that many locals cherish, as the crispness of fall approaches. With October maintaining a similar velocity at 4.2 m/s (9 mph), the winds continue to cycle through a pattern of mild intensity, laying the groundwork for a notable uptick in November, when gusts rise to 5.4 m/s (12 mph). This seasonal dance of the wind reflects the broader climatic shifts in the region, marking September as a pivotal month of change, where the soft summer breezes give way to the more invigorating autumn gusts.

Average September Wind Speed in Saint Joseph

The chart displays monthly wind speed patterns in Saint Joseph, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.24.74.83.93.83.53.43.04.3 m/s4.25.45.1
Data source: Saint Joseph September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Saint Joseph Compares to Other Months

The weather in Saint Joseph 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 Saint Joseph and find detailed weather information for every month.

In September, temperatures in Saint Joseph range from a cool minimum of 6°C (43°F) to a warm maximum of 32°C (90°F), with an average of 20°C (68°F). This month sees about 73 mm (2.9 in) of precipitation over approximately 8 days, and humidity levels hover around 78%. In stark contrast, January brings much colder conditions, with temperatures plunging to a minimum of -25°C (-13°F) and peaking at a maximum of only 14°C (58°F), averaging -2°C (29°F). Precipitation increases slightly to 79 mm (3.1 in) but occurs over more days—approximately 13, with a higher humidity level of 85%. For more detailed insights on January weather, you can check Saint Joseph weather in January.

September and February present starkly contrasting weather conditions. In September, temperatures can range from a cool 6°C (43°F) to a warm 32°C (90°F), with an average of 20°C (68°F). The month sees about 73 mm (2.9 in) of precipitation spread over 8 days, and humidity levels hover around 78%. In sharp contrast, February experiences much harsher conditions, with temperatures plunging to a minimum of -21°C (-6°F) and a maximum of 16°C (61°F), averaging -1°C (30°F). While February receives slightly more precipitation at 76 mm (3.0 in) over 13 days, the humidity is somewhat higher at 85%. For more detailed weather information specific to February, you can check Saint Joseph weather in February.

September and March present contrasting weather patterns, with September enjoying milder temperatures and sunnier days. In September, the temperature ranges from a minimum of 6°C (43°F) to a pleasant average of 20°C (68°F), reaching a maximum of 32°C (90°F) during warmer days. The month also experiences about 73 mm (2.9 in) of precipitation over approximately 8 days, with a humidity level of 78%.

In contrast, March is significantly cooler, with temperatures ranging from a minimum of -14°C (7°F) to an average of 3°C (38°F), peaking at only 21°C (70°F). This month sees slightly higher precipitation at 87 mm (3.4 in), spread over 12 days, and a higher humidity level of 86%. Despite being on the brink of spring, March weather can still feel quite wintry. For more details about March conditions, visit Saint Joseph weather in March.

In comparing September and April weather, it's evident that both months experience distinct climates. September typically boasts milder temperatures with a minimum of 6°C (43°F), an average of 20°C (68°F), and a maximum of 32°C (90°F). In contrast, April starts cooler with a minimum of -5°C (24°F) and an average of 8°C (46°F), peaking at 26°C (78°F). Precipitation is also notable, with September receiving 73 mm (2.9 in) over about 8 days, while April sees more rainfall at 108 mm (4.2 in) across approximately 14 days. Humidity levels are slightly lower in September at 78%, compared to 87% in April, highlighting a more humid atmosphere during the latter month. For a detailed look at the weather conditions, visit Saint Joseph weather in April.

When comparing the weather in September and May, notable contrasts emerge. September features a range of temperatures from a minimum of 6°C (43°F) to a maximum of 32°C (90°F), with an average temperature of 20°C (68°F). The month experiences relatively lower precipitation, with 73 mm (2.9 in) spread over 8 days and humidity at 78%. In contrast, May shows much cooler minimum temperatures, dipping to -1°C (31°F), with an average of 14°C (58°F) and a maximum of 30°C (87°F). However, May is wetter, with 168 mm (6.6 in) of rainfall across 15 days and slightly higher humidity at 81%. For more details, you can visit Saint Joseph weather in May.

When comparing the weather in September and June, notable differences emerge in temperature and precipitation. September typically experiences a wider temperature range, with lows of 6°C (43°F) and highs reaching up to 32°C (90°F), while June starts at a warmer minimum of 10°C (51°F) and peaks at 31°C (89°F). June also sees more rainfall, averaging 133 mm (5.2 in) over 12 days, compared to September's 73 mm (2.9 in) over 8 days. Humidity levels are similar, sitting around 78% in September and slightly higher at 82% in June. For a deeper look into the specifics of June weather, visit Saint Joseph weather in June.

In comparing the weather between September and July, we notice some distinct differences. September offers a broader temperature range, with a minimum of 6°C (43°F) and a maximum that is similar to July’s peak at 32°C (90°F), leading to an average temperature of 20°C (68°F). In contrast, July experiences milder lows at 15°C (59°F) and a slightly higher average of 23°C (74°F). Additionally, September sees less precipitation, with 73 mm (2.9 in) over 8 days, compared to July's 93 mm (3.7 in) over 11 days. Humidity levels are also marginally lower in September at 78%, versus July's 81%. For more details on July weather, visit Saint Joseph weather in July.

Comparing the weather in September to August reveals distinct differences. September experiences a wider temperature range, with a minimum of 6°C (43°F) and a maximum of 32°C (90°F), while August has a milder minimum of 12°C (54°F) and a somewhat equivalent maximum of 31°C (89°F). The average temperature in September is slightly lower at 20°C (68°F) compared to August's average of 23°C (73°F). Both months see similar precipitation levels at 73 mm (2.9 in), but September experiences this over 8 days, while August has it spread over 10 days. Humidity levels are comparable, with September at 78% and August slightly higher at 79%. For more detailed information, you can check Saint Joseph weather in August.

September and October show a marked transition in weather patterns. September boasts warmer temperatures, with a minimum of 6°C (43°F) and an average of 20°C (68°F), but as we move into October, the minimum dips to 1°C (34°F) with an average of 13°C (56°F). While September sees a maximum temperature of 32°C (90°F), October's peak is a milder 29°C (84°F). Precipitation increases significantly in October, with 145 mm (5.7 in) falling over 15 days compared to September's 73 mm (2.9 in) over just 8 days. Humidity also rises slightly from 78% in September to 81% in October. For a more detailed look at October's weather in this region, check out Saint Joseph weather in October.

September and November present stark contrasts in weather conditions. In September, temperatures typically range from a mild 20°C (68°F) on average, with a maximum of 32°C (90°F), creating an inviting atmosphere for outdoor activities. The month experiences a total precipitation of 73 mm (2.9 in) over about 8 days, coupled with a humidity level of 78%. In contrast, November sees a significant drop in temperatures, averaging around 5°C (41°F) and reaching a maximum of 22°C (72°F), with minimums plunging to -9°C (17°F). This month also comes with a similar total precipitation of 74 mm (2.9 in), but it is spread out over more days, totaling 10, while humidity increases to 89%. For more information on November weather specifics, check out Saint Joseph weather in November.

September and December present a stark contrast in weather conditions. In September, temperatures average around 20°C (68°F), with highs reaching up to 32°C (90°F), making it a warm and pleasant month. However, it is also marked by higher humidity levels at 78% and a total of 73 mm (2.9 in) of precipitation over 8 days.

In December, the weather shifts dramatically, with temperatures plummeting to an average of just 2°C (35°F), and lows dipping as low as -17°C (2°F). Despite slightly lower precipitation at 69 mm (2.7 in), it occurs over 11 days, contributing to a much chillier and damp atmosphere, accompanied by increased humidity at 86%. For a more detailed look at the conditions, visit Saint Joseph weather in December.

Compare Saint Joseph's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Saint Joseph

As September arrives in Saint Joseph, the weather begins to shift, offering a refreshing contrast to the sultry summer months. With average temperatures settling around a mild 20°C (68°F), the days are pleasantly warm but not overwhelmingly hot. The humidity remains moderate, creating a comfortable environment perfect for outdoor activities. However, the month does bring some rain, with eight days of precipitation contributing to a total of 73 mm, which helps to nourish the lush landscapes and prepare the region for the transition into cooler autumn days. For more insights on how the weather evolves throughout the year, explore Saint Joseph Climate.