Last updated: February 24, 2025
In September, Chelsea, United States, experiences a vibrant transition toward autumn, with temperatures ranging from a minimum of 8°C (47°F) to a striking maximum of 34°C (93°F). The average temperature settles comfortably at 21°C (71°F), creating a pleasant backdrop for outdoor activities. However, residents should prepare for the possibility of rain, as the month typically sees around 91 mm (3.6 inches) of precipitation spread over 10 days, contributing to a humidity level of 68%. This blend of warmth and occasional showers marks September as a dynamic period in Chelsea's climatic calendar.
As summer fades into autumn, September in Chelsea, United States, experiences a delightful transition in temperatures. With minimums dipping to 8°C (47°F), the air starts to crisp, while the average temperature settles at a comfortable 21°C (71°F). This month boasts a maximum of 34°C (93°F), allowing for lingering warm days, yet it paves the way for the cooler season ahead. The gradual shift from the heat of August to more moderate September temperatures captures the essence of early fall, where outdoor activities remain enjoyable before the chill truly sets in. Overall, September serves as a pleasant bridge between the warmth of summer and the briskness of autumn, making it a favored time for both residents and visitors alike.
In September, Chelsea experiences a moderate precipitation pattern, with 91 mm (3.6 in) of rain falling over 10 days. This marks a slight decrease from the earlier months, particularly August's 126 mm (5.0 in), signaling a gradual transition into fall. While still significant, September's rainfall hints at a drying trend as summer's peak moisture begins to wane. The rainfall is relatively balanced, suggesting a typical early autumn climate, paving the way for the drier conditions often seen in October. Observing these shifts indicates that Chelsea's weather is responding to seasonal changes, shaping the environment as it prepares for the cooler months ahead.
In September, Chelsea experiences a notable shift in humidity, with levels reaching 68%. This month marks a transition from the more humid summer months of July and August, which see lower humidity at 62% and 65%, respectively. As fall approaches, humidity begins to rise again, hinting at the more humid conditions of the upcoming months, especially October’s average of 74%. Overall, the trend showcases a gradual decline from the high humidity of early winter, peaking in January at 84%, through the warmer months, before starting to build again in the fall season. This rhythm of humidity reflects the dynamic climate of Chelsea throughout the year, offering a refreshing reprieve before the wetter months set in.
In September, Chelsea experiences a UV Index of 8, categorizing this month within the very high exposure range, similar to the peak summer months. With a burn time of just 15 minutes, it's crucial to take protective measures against UV rays, as the sun's intensity remains significantly elevated after the summer. Although there’s a slight decrease from the maximum levels observed in July and August, the UV index still mandates caution. As we transition into the fall, the UV Index begins to taper off, but it's wise to stay vigilant—especially as many enjoy outdoor activities in the crisp September air. For more insights on UV levels throughout the year, visit Chelsea UV Index.
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In September, Chelsea experiences a delightful transition from summer's peak, basking in 279 hours of sunshine. This month reflects a slight decline from the vibrant 353 hours of July, but it still benefits from the lingering warmth of summer, outshining the earlier months like January's mere 152 hours. As the year progresses, sunlit hours generally trend downward, with the highest peaks in the summer months and a gradual tapering as autumn sets in. September’s ample sunlight serves as a gentle reminder of summer’s warmth, bridging the gap to the cooler days ahead while still illuminating the vibrant landscapes of Chelsea.
September in Chelsea, United States, carries a 47% chance of sunny weather, mirroring January's likelihood of sun. This month marks a notable transition as it straddles the end of summer and the onset of fall. As the days begin to shorten, the sunshine probability fluctuates, with the previous few months—particularly the dismal 29% in August—showing a dip in sunny days. Interestingly, while September offers a glimmer of hope with a percentage equal to January, this month also hints at the approach of more favorable sunny days as the year progresses, especially when compared to the earlier summer months. As fall approaches, September's sunny weather indicates a promising respite from the fluctuations experienced over the summer, making it a delightful time for outdoor activities in Chelsea.
As September unfolds in Chelsea, United States, daylight begins to wane slightly, with the sun gracing the sky for 12 hours each day. This decrease marks a transition from the vibrant, sun-soaked days of summer, where June, July, and August bask in a maximum of 14 hours of daylight. As we reach the cusp of autumn, the daylight hours are still significantly longer than the winter months, which see a stark drop to 9 hours in both November and December. Overall, September's daylight signifies a gentle shift—a time when nature subtly begins to prepare for the cooler, shorter days ahead, while still offering a generous measure of sunlight to enjoy.
As September unfolds in Chelsea, the wind begins to whisper a gentle transition from summer's calm to autumn's brisk embrace. With an average wind speed of 3.2 m/s (7 mph), this month marks a slight uptick from the languid breezes of July and August, which lingered around 2.5 m/s (6 mph). This subtle increase suggests an invigorating shift as the seasonal warmth wanes, echoing a rhythm seen throughout the year. Interestingly, the breeze in early fall harks back to the more lively speeds of earlier months like March and April, hinting at the dynamic changes yet to come. As nature prepares for the colorful foliage ahead, the September winds in Chelsea serve as a gentle reminder of the ebb and flow of the seasons, inviting both reflection and adventure.
The weather in Chelsea 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 Chelsea and find detailed weather information for every month.
In September, the weather is generally warm, with temperatures ranging from a minimum of 8°C (47°F) to a maximum of 34°C (93°F) and an average of 21°C (71°F). The month sees about 91 mm (3.6 in) of precipitation over approximately 10 days, accompanied by a humidity level of 68%. In contrast, January brings much colder conditions, with temperatures ranging from a frigid minimum of -18°C (0°F) to a maximum of 19°C (66°F) and an average of just 1°C (35°F). January experiences less precipitation, totaling 66 mm (2.6 in) over around 8 days, but it has higher humidity at 84%. These seasonal differences highlight a significant shift from the warmth of late summer to the chill of mid-winter. For more specifics, check out Chelsea weather in January.
September and February exhibit stark contrasts in weather patterns. September boasts a temperate climate with average highs around 21°C (71°F) and occasional peaks reaching 34°C (93°F), while February's temperatures swing dramatically lower, averaging just 3°C (37°F) and dipping as low as -16°C (4°F). Despite both months experiencing about 10 days of precipitation, February tends to be slightly wetter with 107 mm (4.2 in) compared to September's 91 mm (3.6 in). Additionally, February's humidity is higher at 82%, while September sees a more moderate 68%. For a closer look at the February weather specifics, visit Chelsea weather in February.
September and March present quite contrasting weather conditions. In September, temperatures range from a mild 8°C (47°F) at night to a warm 34°C (93°F) during the day, with an average of 21°C (71°F). The month experiences some rainfall, totaling around 91 mm (3.6 in) over approximately 10 days, accompanied by a moderate humidity level of 68%. In contrast, March is significantly cooler, with nighttime temperatures plummeting to -9°C (16°F) and daytime highs reaching just 27°C (80°F), averaging around 6°C (43°F). It also sees slightly higher precipitation at 103 mm (4.0 in) over 10 days, and the humidity is a bit higher at 81%. For more detailed information about Chelsea's weather in March, check out Chelsea weather in March.
September and April present contrasting weather patterns. In September, temperatures range from a mild 8°C (47°F) at night to a warm 34°C (93°F) during the day, with an average of 21°C (71°F). This month experiences 91 mm (3.6 in) of rainfall over about 10 days, accompanied by a humidity level of 68%. In contrast, April starts with cooler nights, dropping to a minimum of -1°C (31°F), and reaches a maximum of 29°C (85°F) during the day, averaging 12°C (53°F). Rainfall is slightly higher at 111 mm (4.4 in) across 12 days, contributing to a higher humidity level of 78%. For a more detailed look at the climate specifics, you can refer to Chelsea weather in April.
In September, temperatures range from a minimum of 8°C (47°F) to a maximum of 34°C (93°F), with an average of 21°C (71°F), offering a warm transition into autumn. However, it experiences less precipitation than May, with 91 mm (3.6 in) over about 10 days, and humidity sits at a comfortable 68%. In contrast, May presents cooler temperatures overall, with minimums of 2°C (37°F) and an average of 17°C (63°F), peaking at 32°C (90°F). May is wetter, receiving 118 mm (4.6 in) of rain over approximately 12 days, and a slightly higher humidity level of 69%. For more details on May's climate, you can check Chelsea weather in May.
In comparing the weather of September and June, we observe some interesting similarities and differences. September features a slightly wider temperature range, with minimums of 8°C (47°F) and maximums reaching 34°C (93°F), while June's temperatures are a bit warmer with minimums of 10°C (50°F) and maximums hitting 35°C (96°F). Precipitation levels are similar, with September receiving 91 mm (3.6 in) over approximately 10 days, compared to June’s 94 mm (3.7 in) over 13 days. Humidity levels are also comparable, hovering around 68% in September and 69% in June. For a more detailed look at June weather, you can visit Chelsea weather in June.
When comparing the weather in September and July, we can see some distinct differences. September experiences a broader temperature range, with minimums dropping to 8°C (47°F) and maximums reaching 34°C (93°F), while July maintains milder nights with a minimum of 16°C (61°F) and maximums soaring to 36°C (97°F). Additionally, September has higher humidity levels at 68% compared to July's 62%, resulting in a more humid feel despite the overall cooler averages. Precipitation is also more frequent in July, totaling 144 mm (5.6 in) across 14 days, whereas September sees 91 mm (3.6 in) over 10 days. For more detailed insights into July's climate, you can explore Chelsea weather in July.
In comparing the weather between September and August, September presents a notable drop in minimum temperatures, averaging around 8°C (47°F) compared to August's milder 15°C (60°F). Despite the average temperature in September being 21°C (71°F), it still lags behind August's warmer average of 25°C (77°F). Furthermore, while both months experience rainfall, September sees a decrease in total precipitation, with 91 mm (3.6 inches) over 10 days versus August's 126 mm (5.0 inches) over 14 days. Humidity levels in September are slightly higher at 68%, compared to 65% in August. For more details on the weather specific to August, you can visit Chelsea weather in August.
September typically experiences warmer temperatures, with highs averaging around 21°C (71°F) and reaching up to 34°C (93°F), while October sees a notable decline, with average temperatures dropping to 16°C (61°F) and nighttime lows nearing 3°C (37°F). Both months can have high temperatures reaching the same peak of 34°C (93°F), but October brings increased precipitation at 130 mm (5.1 in) compared to September's 91 mm (3.6 in), while also displaying a slight rise in humidity, from 68% in September to 74% in October. For those interested in the specifics of October weather, more details can be found here: Chelsea weather in October.
In September, the weather is generally warm, with average temperatures ranging from a minimum of 8°C (47°F) to a maximum of 34°C (93°F), creating a pleasant atmosphere for outdoor activities. The month receives around 91 mm (3.6 in) of precipitation over approximately 10 days, with humidity levels at 68%. In contrast, November sees a significant drop in temperature, with averages between -9°C (17°F) and a maximum of 25°C (76°F), leading to a much cooler climate. Additionally, November experiences slightly less precipitation at 82 mm (3.2 in) over 9 days, but the humidity increases to 82%, resulting in a chillier feel. For more specific details on November weather, you can visit Chelsea weather in November.
September and December weather in Chelsea exhibit stark contrasts. In September, temperatures range from a mild minimum of 8°C (47°F) to a warm maximum of 34°C (93°F), with an average of 21°C (71°F). The month experiences about 91 mm (3.6 in) of precipitation over 10 days, accompanied by a relative humidity of 68%. In contrast, December sees much cooler conditions, with temperatures dipping from a minimum of -11°C (13°F) to a maximum of 19°C (66°F), averaging just 4°C (39°F). Despite slightly higher precipitation at 102 mm (4.0 in), it also spans 10 days, and the humidity increases to 80%. For a closer look at seasonal changes, check out Chelsea weather in December.
As summer transitions into autumn, September in Chelsea offers a delightful mix of warmth and coolness, setting it apart from the sweltering months preceding it. With temperatures averaging a comfortable 21°C (71°F), this month sees pleasant days where afternoons can still sizzle with highs around 34°C (93°F), while early mornings and evenings can surprise with cooler spells, dipping to 8°C (47°F). However, don't forget your umbrella; with about 91 mm (3.6 in) of rain falling over around 10 days, you'll want to be prepared for the occasional shower. The humidities typical of summer linger at 68%, adding a touch of mugginess to the otherwise crisp fall air. For a deeper dive into what to expect throughout the year, check the detailed insights on the Chelsea Climate.