Last updated: February 24, 2025
In September, New Castle, United States, experiences a delightful transition into fall, marked by an average temperature of 18°C (65°F). The maximum temperature can reach up to 30°C (86°F), while nights cool down to a cozy minimum of 7°C (46°F). With humidity levels hovering around 71%, the air feels comfortably mild. Although the region sees about 78 mm (3.1 in) of precipitation spread over 8 days, these occasional showers often enhance the vibrant autumn scenery, making September a picturesque time to explore the area.
In September, New Castle experiences a delightful transition as summer gives way to fall. The temperatures start to cool, with minimum values around 7°C (46°F) and a pleasant average reaching 18°C (65°F), making it a comfortable time for outdoor activities. The warm maximum temperature of 30°C (86°F) still lingers, allowing for those final sun-soaked days before the chilly air settles in for the autumn months. This month serves as a perfect reminder of the warmth of summer while hinting at the cooler days to come, making it an ideal time for both exploration and relaxation in this vibrant region.
In September, New Castle experiences a moderate precipitation level with 78 mm (3.1 in) of rainfall spread across 8 days. This marks a slight decline from the summer's heavier rains, particularly July's 123 mm (4.8 in), suggesting a transition towards drier autumn months. Interestingly, September's rainfall is comparable to the previous month, August, which recorded only 71 mm (2.8 in) over 9 days. This pattern reflects a gradual decrease in precipitation as the seasons change, paving the way for more substantial rains in October, with an expected 142 mm (5.6 in). Overall, September serves as a bridge between the lush, wet summer and the forthcoming autumnal deluge, offering a hint of what’s to come.
As summer fades and autumn approaches in New Castle, September experiences a modest rise in humidity, with levels averaging 71%. This marks a slight increase from August's 66%, reflecting the transition from the drier summer months. Interestingly, the humidity begins its gradual climb again after hitting a low point in July and August, making September feel less oppressive than the peak summer heat, yet still reminding residents of the moisture-laden months that lie ahead. This cyclical pattern suggests that as New Castle moves towards the cooler months, the air becomes more saturated, setting the stage for the wetter conditions often characteristic of fall.
As September rolls into New Castle, the UV Index reflects a significant drop from the summer months, settling at a high level of 7. While still indicative of strong sun exposure, this marks a shift from the peak very high readings of 9 and 10 experienced in July and August. With a burn time of 25 minutes, residents and visitors should remain cautious, embracing sun safety measures while enjoying the outdoor activities that early autumn offers. This transition into fall reminds us of the importance of monitoring UV levels year-round, especially as they fluctuate through the seasons. For more detailed insights on UV exposure, visit New Castle UV Index.
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As summer fades, September in New Castle continues to bask in the warmth of sunshine, offering an impressive 285 hours of bright days. This marks a slight decline from the striking peak of 337 hours experienced in August, yet it remains significantly higher than the winter months such as January, which only boasts 150 hours. Notably, September's sunshine plays a pivotal role in easing the transition into autumn, balancing daily warmth with the beginnings of cooler breezes. With daylight hours steadily decreasing as the year progresses, this month still provides ample opportunity to soak up the lingering summer rays before they retreat. Overall, September shines as a beautiful connector between the vitality of summer and the comforting embrace of fall.
In September, New Castle, United States, experiences a 44% chance of sunny weather, making it one of the more favorable months for sunshine as summer transitions into fall. While the likelihood of sun is higher than during the peak summer months of July and August, which see only 32%, it still lags behind the promising 61% chance found in March. Overall, September stands out as a month of potential brightness amid a backdrop of fluctuating weather patterns throughout the year, suggesting that visitors and locals alike can expect a mix of sun and clouds as autumn begins to unfold.
In September, New Castle experiences a noticeable shift in daylight, with the duration settling at 12 hours. This marks a decline from the 14 hours in May and 15 hours in June, illustrating the transition from the longer days of summer to the shorter days of fall. As the year progresses, daylight steadily decreases, dropping to 10 hours by October and maintaining a 9-hour limit through the winter months of November and December. This rhythm of daylight not only reflects changing seasons but also influences the daily activities and moods of the community, inviting a blend of outdoor adventures and cozy indoor gatherings as summer gives way to autumn.
As September rolls in, New Castle experiences a subtle shift in its wind patterns, with an average wind speed of 3.9 m/s (9 mph). While this marks a slight uptick from the laziness of summer, where winds dropped to a gentle 3.3 m/s (7 mph) in August, the breezes remain relatively mild compared to earlier months. Interestingly, the spring months started off robust, peaking at 5.2 m/s (12 mph) in March, before gradually declining through the summer. Now, as autumn approaches, one can feel the refreshing whispers of September winds, hinting at the seasonal transitions ahead, which will soon bring increased gusts in October. This gradual shift in wind speed not only reflects the changing season but also sets the stage for the refreshing breezes of fall, inviting residents to embrace the new atmospheric rhythm.
The weather in New Castle 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 New Castle and find detailed weather information for every month.
September and January showcase starkly contrasting weather conditions. In September, temperatures range from a mild 7°C (46°F) to a warm 30°C (86°F), with an average of 18°C (65°F), while January's temperatures plummet to a minimum of -19°C (-2°F) and a maximum of 17°C (64°F), averaging around -1°C (30°F). Both months see similar precipitation levels, at 78-79 mm (3.1 in) over approximately 8 days, but January's higher humidity at 86% contributes to a noticeably colder feel compared to September's 71% humidity. For a detailed look at January weather, visit New Castle weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures range from a milder minimum of 7°C (46°F) to a warm maximum of 30°C (86°F), with an average of 18°C (65°F). The month experiences moderate rainfall, totaling 78 mm (3.1 in) over about 8 days, accompanied by a humidity level of 71%. In contrast, February showcases much colder temperatures, with a minimum of -16°C (4°F) and a maximum reaching only 17°C (64°F), averaging around 0°C (32°F). This month also sees increased precipitation of 98 mm (3.9 in) over approximately 11 days, coupled with high humidity at 84%. For more details on the February weather in New Castle, you can check New Castle weather in February.
When comparing the weather of September and March, it's evident that these months present stark contrasts. September enjoys milder temperatures with a minimum of 7°C and an average reaching 18°C, peaking at 30°C, while March is significantly colder, with a minimum of -14°C and an average temperature of only 2°C, though it can rise to 17°C at times. Precipitation is more frequent in March with 94 mm over 10 days compared to September's 78 mm over 8 days, which contributes to a higher humidity level of 82% in March versus 71% in September. For a closer look at the specifics, you can check New Castle weather in March.
In comparing the weather conditions of September and April, we see notable differences in temperature and precipitation. September enjoys milder temperatures, with averages around 18°C (65°F) and maximums reaching up to 30°C (86°F), while April experiences cooler averages of 8°C (46°F), with maximums only peaking at 24°C (76°F). Additionally, April tends to be wetter, receiving about 143 mm (5.6 in) of precipitation over 13 days, compared to September's 78 mm (3.1 in) over just 8 days. Both months have relatively high humidity, with April slightly higher at 80% compared to September's 71%. For more detailed information, you can refer to New Castle weather in April.
In September, temperatures can range from a chilly 7°C (46°F) at night to a warm 30°C (86°F) during the day, resulting in a comfortable average of 18°C (65°F). The month experiences about 78 mm (3.1 in) of precipitation over roughly 8 days, with humidity hovering around 71%. In contrast, May features cooler temperatures, with a minimum of 2°C (37°F), an average of 13°C (55°F), and a maximum of 27°C (82°F). It sees slightly higher precipitation at 83 mm (3.3 in) across 11 days, while humidity levels are marginally higher at 72%. For more details, check New Castle weather in May.
When comparing the weather in September and June, both months exhibit similar temperature ranges, with minimums hovering around 7-8°C (46-47°F) and maximums reaching up to 30°C (86°F). The average temperature remains consistent at 18°C (65°F) in both months. However, September experiences slightly less precipitation at 78 mm (3.1 in) over about 8 days, compared to June's 88 mm (3.5 in) over approximately 10 days. Humidity levels are also quite close, with September at 71% and June at 72%. For a more detailed look at June's weather specifics, check out New Castle weather in June.
In comparing the weather of September and July, it is evident that July tends to be warmer overall, with average temperatures reaching 22°C (71°F) and a maximum high of 31°C (88°F). In contrast, September has a lower average temperature of 18°C (65°F), with maximums reaching up to 30°C (86°F). While July experiences a higher minimum temperature of 13°C (56°F), September's cooler nights can drop as low as 7°C (46°F). Precipitation is also more prevalent in July, with 123 mm (4.8 in) of rain over 12 days compared to September's 78 mm (3.1 in) over 8 days; however, September has a slightly higher humidity at 71% versus July's 67%. For more detailed insights, you can check New Castle weather in July.
In comparison to August, September typically experiences cooler temperatures, with a minimum of 7°C (46°F) and an average of 18°C (65°F) compared to August's minimum of 13°C (55°F) and average of 22°C (71°F). Both months feature similar maximum temperatures, with September peaking at 30°C (86°F) and August at 31°C (88°F), but September tends to have slightly more rainfall, with 78 mm (3.1 in) across 8 days compared to August's 71 mm (2.8 in) over 9 days. Additionally, September has higher humidity at 71%, while August maintains a lower humidity level of 66%. For more details about August weather patterns, you can check New Castle weather in August.
September and October bring distinct changes in weather as summer transitions into fall. In September, temperatures range from a minimum of 7°C (46°F) to a maximum of 30°C (86°F), with an average of 18°C (65°F). The month experiences moderate rainfall, totaling 78 mm (3.1 in) over about 8 days, accompanied by a humidity level of 71%. In contrast, October sees a significant drop in temperatures, with a minimum of 1°C (34°F) and an average of 13°C (56°F), peaking at 25°C (78°F). Rainfall increases to 142 mm (5.6 in), spread across 11 days, and humidity rises slightly to 78%. For more details on October weather, visit New Castle weather in October.
The weather in September is characterized by a more moderate temperature range, with minimums around 7°C (46°F) and maximums reaching up to 30°C (86°F), making it a pleasant month for outdoor activities. In contrast, November sees a notable drop in temperatures, with minimums dipping to -12°C (11°F) and a cooler average of 6°C (43°F). Additionally, November experiences more precipitation, with 108 mm (4.3 in) over 11 days compared to September's 78 mm (3.1 in) over 8 days. The increase in humidity from 71% in September to 84% in November further emphasizes the transition into the chillier late fall season. For more detailed insights, you can check New Castle weather in November.
In comparing the weather of September and December, there's a striking contrast. September boasts a comfortable average temperature of 18°C (65°F), with maximum highs reaching up to 30°C (86°F), while December's average drops significantly to just 1°C (34°F), with lows plunging to -19°C (-1°F). Additionally, December experiences more precipitation, totaling 133 mm (5.2 in) over 10 days, compared to September's 78 mm (3.1 in) across 8 days. Humidity also rises slightly in December to 81%, compared to September's 71%. This dramatic shift not only highlights the transition from a warm late summer to a cold winter but also underscores the necessity of adjusting to the colder climate, as detailed in New Castle weather in December.
September in New Castle marks a transition into cooler temperatures and a unique blend of warm days and crisp nights. Unlike the summer months that boast consistent heat, September offers a refreshing dip in temperatures, making outdoor activities more enjoyable. While the humidity remains a bit high, the relatively low precipitation allows residents and visitors alike to make the most of this delightful month. Despite the occasional rain, the distinct character of September often draws people outside to relish the beautiful scenery. For a comprehensive overview of how September’s weather fits into the overall patterns, check out the New Castle Climate.