Last updated: February 24, 2025
September in Arlington, United States, showcases a dynamic range of weather, with maximum temperatures soaring to 36°C (97°F), while average conditions hover around a comfortable 22°C (72°F). The month also presents cooler days, with temperatures dipping to a brisk 5°C (42°F). Rainfall is a frequent visitor, contributing 95 mm (3.8 in) over 11 days, accompanied by a notable humidity level of 75%. This blend of warmth, occasional precipitation, and moisture creates an engaging atmosphere, ideal for enjoying the fading summer and transitioning into autumn.
September in Arlington ushers in a delightful transition from summer’s heat, characterized by temperatures that range from a minimum of 5°C (42°F) to a maximum of 36°C (97°F). The average temperature settles at a comfortable 22°C (72°F), offering a pleasant reprieve for outdoor activities. As the month progresses, the warmth begins to diminish, hinting at the cooler days ahead. This shift not only marks a change in weather but also in lifestyle, as residents embrace the crispness of autumn. September's temperatures reflect a blend of lingering summer warmth and the early signs of fall, making it a vibrant and dynamic month in Arlington.
September sees precipitation in Arlington, United States, amounting to an average of 95 mm (3.8 in) over 11 days. This marks a slight decrease from the wetter months of July and August, where the rainfall peaked at 157 mm (6.2 in) and 140 mm (5.5 in), respectively. As summer gives way to autumn, September’s rainfall hints at the changing seasons, with moisture levels transitioning closer to those seen in April and October. This gradual shift signifies a trend towards lighter, more sporadic showers that invite the crispness of fall, providing a refreshing break from the intense summer heat. The relatively moderate precipitation also suggests a balance, as Arlington prepares for the drier days ahead.
September ushers in a gentle shift in humidity levels in Arlington, United States, recording 75% humidity—slightly higher than the preceding summer months, which saw lows around 72% in August and 74% in July. This subtle uptick reflects the onset of autumn, characterized by a gradual increase as the warmth of summer recedes. As the city transitions into fall, humidity levels begin to creep back up, setting the stage for the wetter months ahead, particularly October, which typically sees a rise to 81%. This trend illustrates Arlington's unique climate rhythm, where the summer heat gives way to a refreshing, yet still humid, autumn atmosphere.
As September rolls into Arlington, the UV Index remains notably high at 8, signaling that this month still demands caution when spending time outdoors. With a burn time of just 15 minutes, sun exposure is critical, tapering slightly from the peak summer months but still classified as very high. This trend indicates a gradual decline from the intense UV rays experienced in July and August, where the Index reached its annual maximum of 10. As we transition into fall, the UV Index will continue to decrease, but for now, residents should stay vigilant. To learn more about daily UV levels, check out Arlington UV Index.
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September in Arlington shines with an impressive 277 hours of sunshine, marking a beautiful transition from the intense brightness of summer. As the days grow shorter, the sun continues to bless the region with a significant amount of light, following a peak of 356 hours in July. The month stands out as a vibrant time, nestled comfortably between the lush summer months and the cooler autumn days, capturing a lingering warmth that invites outdoor activities. Although there's a slight decrease compared to the summer highs, September maintains a commendable brightness, ensuring that residents can enjoy those soft, sunlit afternoons before the fall truly settles in. Overall, the trend reveals a steady abundance of sunshine, especially in the warmer months, creating a delightful atmosphere for both locals and visitors alike.
In Arlington, the likelihood of sunny weather peaks in September, with an impressive 53% chance of sunshine compared to other months of the year. This marks a notable shift from the summer months, where the chances dwindle, with July and August seeing only 49% and 34%, respectively. As the heat of summer recedes, September offers a refreshing transition, presenting clearer skies more frequently. Interestingly, this month also leads into the fall, where sunshine opportunities begin to fluctuate, with October dropping to 39%. Overall, September stands out as a bright spot in Arlington’s weather calendar, inviting residents and visitors to embrace the delightful warmth and sunshine before the chill of autumn sets in.
As summer bids farewell in September, Arlington enjoys a gentle transition from the abundant 14 hours of daylight seen in July and June to a more moderate 12 hours. This gradual decrease signals the onset of autumn, where daylight begins to wane. Following the trend of longer days in spring, which peak in May and June, September subtly shifts the focus towards shorter daylight periods as October approaches with its 11 hours. The rhythm of the seasons is evident here, as nature prepares for the cozy embrace of fall, inviting residents to savor the crisp, sunlit days that herald the change in weather.
As September arrives in Arlington, the transition into fall brings a gentle increase in wind speed, averaging 2.6 m/s (6 mph). This modest uptick from the summer lows marks a departure from the 1.9 m/s (4 mph) experienced in August. The gradual shift in wind patterns highlights a consistent seasonal rhythm, where the winds typically pick up after the sultry summer months, reflecting nature's preparation for the cooler days ahead. With the breeze becoming more noticeable, September offers a refreshing backdrop for outdoor activities, making it a delightful time to enjoy the changing landscape. As autumn unfolds, wind speeds will continue to oscillate, yet September sets the stage with its inviting gusts, heralding the beauty of the season.
The weather in Arlington 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 Arlington and find detailed weather information for every month.
In September, temperatures in Arlington range from a mild 5°C (42°F) at night to a warm 36°C (97°F) during the day, with an average temperature of 22°C (72°F). The month experiences significant humidity at 75%, coupled with 95 mm (3.8 in) of precipitation spread over 11 days, indicating a transition towards fall.
In contrast, January brings a stark change in climate, where temperatures drop dramatically, ranging from a frigid -15°C (5°F) to a daytime high of 22°C (71°F), with an average of only 3°C (37°F). Despite the colder temperatures, January sees less total precipitation at 61 mm (2.4 in) over 8 days, and the humidity rises slightly to 84%. For more details about January weather in Arlington, visit Arlington weather in January.
September and February present starkly contrasting weather conditions. In September, temperatures range from a mild 5°C (42°F) at night to soaring highs of 36°C (97°F) during the day, with an average of 22°C (72°F). The month experiences about 95 mm (3.8 inches) of precipitation over 11 days, coupled with a humidity level of 75%. In contrast, February brings much colder temperatures, with lows plummeting to -16°C (4°F) and daytime highs reaching only 28°C (82°F), making the average a chilly 5°C (41°F). Precipitation is slightly higher at 98 mm (3.9 inches) over the same number of days, and humidity also increases to 83%. For more details, you can visit Arlington weather in February.
September and March offer distinct weather profiles, highlighting the transition between summer and winter. In September, temperatures range from a minimum of 5°C (42°F) to a maximum of 36°C (97°F), creating warm days with an average of 22°C (72°F). However, it also experiences notable humidity at 75% and higher precipitation, totaling 95 mm (3.8 in) over 11 days. In contrast, March experiences cooler temperatures, with a minimum of -7°C (20°F) and a maximum of 28°C (83°F), resulting in an average of just 8°C (46°F). While March has slightly lower precipitation at 87 mm (3.4 in) over 10 days, it also sees higher humidity at 83%. To explore more about March weather in detail, you can check Arlington weather in March.
When comparing the weather in September and April, one can observe notable differences in temperature and humidity levels. September boasts warmer temperatures, with an average of 22°C (72°F) and a maximum of 36°C (97°F), making it significantly hotter than April, which has an average temperature of 14°C (57°F) and a maximum of 32°C (91°F). Both months experience similar precipitation levels, with September receiving 95 mm (3.8 in) and April slightly higher at 100 mm (4.0 in), each spanning approximately 11 days of rain. However, September has a lower humidity rate of 75% compared to April's 81%, resulting in a more comfortable atmosphere in the earlier fall month. For detailed insights into April's weather, you can check Arlington weather in April.
In comparing the weather of September and May, we see distinct differences in temperature and precipitation. September tends to have warmer temperatures, with averages reaching up to 22°C (72°F) and maximums hitting 36°C (97°F). In contrast, May has slightly cooler temperatures, averaging around 19°C (66°F) and peaking at 34°C (94°F). When it comes to rainfall, May is wetter, receiving 127 mm (5.0 in) over 13 days, compared to September's 95 mm (3.8 in) over 11 days. Notably, humidity levels remain high in both months, with September at 75% and May at 78%. For more detailed insights, check out Arlington weather in May.
When comparing the weather in September and June, both months exhibit the potential for high temperatures, with maximums reaching up to 36°C (97°F) in September and 36°C (98°F) in June. However, September tends to have a slightly lower average minimum temperature of 5°C (42°F) compared to June's 9°C (48°F). On the precipitation front, June is wetter, receiving 118 mm (4.7 in) compared to September's 95 mm (3.8 in), with rain occurring on about 12 days in June versus 11 days in September. Additionally, humidity levels are comparable, with September at 75% and June slightly higher at 79%. For a more detailed look at June's weather, you can visit Arlington weather in June.
When comparing the weather in September and July, notable differences emerge. September experiences a broader temperature range, with minimums dropping to 5°C (42°F) and maximums reaching up to 36°C (97°F), resulting in an average temperature of 22°C (72°F). In contrast, July has milder minimum temperatures of 15°C (59°F) and warmer maximums averaging 38°C (101°F), leading to a higher average of 27°C (81°F). Precipitation is also notably different; September sees 95 mm (3.8 in) spread over 11 days, while July receives 157 mm (6.2 in) over 12 days, indicating a wetter month. Humidity remains fairly consistent, with September at 75% and July slightly lower at 74%. For more specifics, you can explore Arlington weather in July.
In August, temperatures were generally warmer, with a minimum of 14°C (58°F) and an average of 25°C (77°F), peaking at a high of 37°C (99°F). The month also experienced more rainfall, totaling 140 mm (5.5 in) over 15 days, accompanied by slightly lower humidity at 72%. In contrast, September saw a drop in temperatures, with a minimum of 5°C (42°F) and an average of 22°C (72°F), reaching a maximum of 36°C (97°F). Although it was still warm, September was slightly drier, recording 95 mm (3.8 in) of precipitation over 11 days and maintaining a higher humidity level of 75%. For more detailed information on August weather, check Arlington weather in August.
September and October exhibit notable differences in weather patterns. September tends to be warmer, with average temperatures around 22°C (72°F) and maximums reaching up to 36°C (97°F). In contrast, October sees a drop in average temperatures to 17°C (62°F), with a minimum of 1°C (34°F). While both months experience similar maximum temperatures, precipitation increases slightly in October to 104 mm (4.1 in), although it falls over just 9 days compared to 11 days in September. Additionally, October's humidity rises to 81%, making the air feel a bit more oppressive. For more detailed information, you can check out Arlington weather in October.
September and November present contrasting weather conditions. In September, temperatures range from a minimum of 5°C (42°F) to a maximum of 36°C (97°F), with an average of 22°C (72°F). This month typically experiences 95 mm (3.8 in) of precipitation over 11 days, alongside a humidity level of 75%. In contrast, November sees significantly cooler temperatures, with a minimum of -6°C (21°F) and a maximum of 25°C (78°F), averaging just 8°C (47°F). This month receives slightly less precipitation at 81 mm (3.2 in) across 7 days, although humidity levels increase to 85%. For more detailed information on November's weather, you can visit Arlington weather in November.
September and December showcase contrasting weather patterns. September tends to be warm, with average temperatures around 22°C (72°F) and maximums reaching up to 36°C (97°F), while experiencing significant humidity at 75% and 95 mm of precipitation over 11 days. In stark contrast, December brings much cooler conditions, with average temperatures dropping to 5°C (41°F) and a maximum of 20°C (69°F). Precipitation remains relatively stable at 93 mm over 9 days, but the humidity increases to 84%, creating a noticeably crisp atmosphere. For more details about the weather in December, check out Arlington weather in December.
As September arrives in Arlington, a noticeable shift in weather sets the stage for a transitional month. While summer's warmth may linger with temperatures reaching the heights of 36°C, the average cools down to a more comfortable 22°C, providing a welcome respite from the sweltering summer heat. With 95 mm of precipitation spread over 11 days, the month showcases a characteristic increase in humidity at 75%, hinting at the forthcoming fall season. This blend of warmth and moisture creates an inviting atmosphere, making September a unique time to experience Arlington’s changing climate. For more detailed insights, check out the full Arlington Climate.