September weather forecast
Connecticut, USA

September in Connecticut marks the beginning of the fall season, with noticeable changes in temperature and a reduction in humidity. The hot summer weather begins to give way to milder conditions, though the transition can vary throughout the state.

Average high temperatures decrease to the range of 65°F (18.3°C) to 70°F (21.1°C), especially in northern and inland areas. Coastal regions might experience slightly warmer conditions due to the proximity to water bodies.

Rainfall remains consistent with the annual range of 44" (1118mm) to 48" (1219mm), but thunderstorms become less frequent. Precipitation may still occur but often in the form of gentler rain showers rather than intense storms.

Humidity continues to decrease, contributing to the more comfortable and crisp weather associated with the beginning of fall. The oppressive humidity of the summer months is largely gone, replaced by fresher and more invigorating air.

The decrease in temperature and humidity also brings the onset of colorful foliage. The transformation begins in the north and gradually moves to the south, with leaves turning vibrant shades of red, orange, and yellow.

September's weather in Connecticut reflects a clear transition from summer to fall, characterized by milder temperatures, reduced humidity, and the beginning of the state's famous foliage season. The changes are often gradual, with the warmth of summer lingering in the early part of the month before giving way to the unmistakable signs of fall. The shift from the heat and humidity of August to the cooler and more comfortable conditions of September is often welcome, heralding the arrival of one of New England's most picturesque and pleasant seasons.

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• Hartford - September »
  The month with the least rainfall in Hartford is September, when the rain falls for 8.2 days and typically collects 0.43" (11mm) of precipitation. The month with the least rainfall in Hartford is September, when the rain falls for 8.2 days and typically collects 0.43" (11mm) of precipitation.
• New Haven - September »
  In September, in New Haven the rain falls for 13.4 days. In September, the average ocean temperature in New Haven is 68.7°F (20.4°C).
• Stamford - September »
  In Stamford in September, the average water temperature is 68.9°F (20.5°C). Stamford experiences an average temperature drop to a refreshing 61.9°F (16.6°C) during September nights.
• Bridgeport - September »
  On the first day of September in Bridgeport sunrise is at 6:19 am and sunset at 7:26 pm. In Bridgeport, during September, the rain falls for 13.5 days and regularly aggregates up to 2.56" (65mm) of precipitation.
• Waterbury - September »
  On the first day of September in Waterbury sunrise is at 6:18 am and sunset at 7:26 pm. In Waterbury in September, it is raining for 13 days, with typically 2.13" (54mm) of accumulated precipitation.
• Norwalk - September »
  In Norwalk in September, during 13.4 rainfall days, 2.72" (69mm) of precipitation is typically accumulated. September in Norwalk ushers in the fall season, with temperatures retreating from the summer highs.
• Danbury - September »
  In Danbury, during September, the rain falls for 9.7 days and regularly aggregates up to 0.67" (17mm) of precipitation. In Danbury, during September, the rain falls for 9.7 days and regularly aggregates up to 0.67" (17mm) of precipitation.
• New Britain - September »
  The month with the least rainfall in New Britain is September, when the rain falls for 12.5 days and typically collects 1.97" (50mm) of precipitation. In New Britain, during September, the rain falls for 12.5 days and regularly aggregates up to 1.97" (50mm) of precipitation.
• Bristol - September »
  On the first day of September in Bristol, Connecticut, sunrise is at 6:17 am and sunset at 7:25 pm. In Bristol, in September, during 13.6 rainfall days, 2.24" (57mm) of precipitation is typically accumulated.
• Meriden - September »
  The month with the least rainfall in Meriden is September, when the rain falls for 12.5 days and typically collects 1.97" (50mm) of precipitation. On the first day of September in Meriden, sunrise is at 6:17 am and sunset at 7:25 pm.
• Milford - September »
  In September, the average ocean temperature in Milford is 68.7°F (20.4°C). In Milford, during September, the rain falls for 13.5 days and regularly aggregates up to 2.4" (61mm) of precipitation.
• West Haven - September »
  The month with the least rainfall in West Haven is September, when the rain falls for 13.4 days and typically collects 2.24" (57mm) of precipitation. The month with the least rainfall in West Haven is September, when the rain falls for 13.4 days and typically collects 2.24" (57mm) of precipitation.