Last updated: February 24, 2025
September in Annapolis, United States, brings a delightful mix of warm days and crisp nights. With maximum temperatures reaching up to 32°C (90°F) and an average of 23°C (73°F), the month invites both locals and visitors to enjoy outdoor activities. However, a cool minimum temperature of 11°C (52°F) reminds us that fall is around the corner. Rain plays a subtle role, with a total precipitation of 113 mm (4.5 in) over approximately 10 days, contributing to the region's lush scenery. The humidity level, hovering at 75%, adds to the day's warmth, creating a characteristic late summer vibe in this charming coastal city.
As summer fades into autumn, Annapolis experiences a delightful transition in September, marked by pleasantly warm temperatures. The month begins with a minimum temperature of around 11°C (52°F), while the average climbs to a comfortable 23°C (73°F). This warmth peaks at a maximum of 32°C (90°F), closely resembling the lingering heat of August, but with a noticeable drop in nighttime temperatures, indicating the approaching autumn. The city's climate during September provides an inviting backdrop for outdoor activities, as residents and visitors alike enjoy the blend of summer's warmth with the crispness hinting at the changing seasons ahead.
In September, Annapolis experiences a notable dip in precipitation, averaging 113 mm (4.5 inches) over 10 rainy days. This marks a decrease from the wetter summer months of July and August, where precipitation peaked at 174 mm (6.9 inches) and 159 mm (6.3 inches), respectively. The transition into fall brings a gentle shift, as the city prepares for cooler temperatures and changing foliage. While September's rainfall is substantial, it sets the stage for October's slightly higher average of 127 mm (5.0 inches), maintaining the city's vibrant seasonal rhythm. Overall, the trend indicates a gradual tapering of summer rains, paving the way for the pleasant autumnal climate ahead.
In September, Annapolis experiences a slight uptick in humidity, reaching 75%, following the drier summer months of July and August, which recorded 74% and 72% respectively. This rise signals the beginning of the fall season, where humidity levels begin their gradual ascent towards winter. Interestingly, after a decline from the peak levels in the winter months, September's humidity is still considerably lower than the year's highest readings of 84% witnessed in January and December. As autumn sets in, residents can anticipate a shift towards more moisture-laden air, with humidity levels steadily climbing again, culminating in 85% by November. This trend illustrates the cyclical nature of Annapolis's climate, characterized by a gentle ebb and flow of humidity throughout the seasons.
As summer fades, September in Annapolis sees a UV Index of 8, maintaining a very high exposure category with a burn time of just 15 minutes. This month marks a slight decrease from the intensity of the preceding months, yet caution is still advised for outdoor activities, as the sun remains potent. Following a trend of rising UV levels through spring and summer—from a moderate 3 in January to peak values of 10 in both June and July—early fall continues to encourage awareness about sun safety. With the temperature dropping and sunlight becoming scarce, September serves as a reminder to protect your skin even as the season transitions. For more information on UV levels throughout the year, visit Annapolis UV Index.
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As summer wanes, September in Annapolis showcases a delightful transition, offering 281 hours of sunshine. While this is a slight decline from the sun-drenched heights of July, which boasts a peak of 359 hours, it remains an impressive month for sunlight. The gradual decrease mirrors the seasonal shift, following a vibrant summer of 339 hours in June and 329 hours in August. This month signifies the onset of autumn, yet still presents plenty of opportunities for outdoor activities bathed in golden light, making it a perfect time to enjoy the lingering warmth before the sun sets on the longer nights ahead. Overall, Annapolis shines brightly as it eases into fall, providing a comforting reminder of the sun's steadfast presence even as the days begin to shorten.
September in Annapolis brings a pleasant shift towards sunnier weather, boasting a 55% chance of sunshine. This marks a notable increase from the summer months, particularly August, which sees a decline to 35%. The transition is refreshing as the city moves from the wetter, hotter days of summer into early autumn. While the likelihood remains higher than several months like October and January, it's particularly intriguing to see how September stands out with its vibrant blue skies, making it a favored time for outdoor activities. Overall, this month serves as a perfect bridge between the lingering warmth of summer and the crispness of fall, inviting both locals and visitors to enjoy the beauty of Annapolis.
As September unfolds in Annapolis, daylight begins to gradually wane, providing a gentle transition from the vibrant summer months. After basking in 14 hours of daylight during the peak of summer in June, July, and August, the city experiences a soft decline to 12 hours of daylight this month. This marks a subtle shift as autumn approaches, inviting shorter days and cooler breezes. The patterns in daylight duration highlight a rhythmic ebb and flow throughout the year; January’s brief 9 hours gradually lengthens through spring, peaking in the summer before navigating back into the cozy embrace of shorter days in the fall. September beautifully exemplifies this annual cycle, balancing the remnants of summer brightness with the anticipation of autumn's arrival.
As September arrives in Annapolis, the average wind speed breathes a gentle reminder of the summer's gradual shift into fall. With winds picking up to 3.6 m/s (8 mph), there's a subtle increase from the languid summer months when speeds dipped to a low of 2.7 m/s (6 mph) in August. This moderate wind rejuvenation signals the approach of autumn, following a seasonal trend where speeds generally rise as the year progresses toward the cooler months. While September's winds deliver refreshing breezes, they also form part of a pattern that sees the months from November to the end of the year consistently hover around 4.1 m/s (9 mph), showcasing a revitalization of gusts that playfully dance through the city, making it a delightful time for outdoor strolls by the Chesapeake.
The weather in Annapolis 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 Annapolis and find detailed weather information for every month.
September and January present two starkly contrasting weather profiles. In September, temperatures soar with a minimum of 11°C (52°F) and an average of 23°C (73°F), peaking at a warm 32°C (90°F). The month also sees substantial precipitation totaling 113 mm (4.5 in) over 10 days, coupled with a humidity level of 75%. In sharp contrast, January experiences frigid conditions, with a minimum temperature plummeting to -13°C (10°F) and an average of just 3°C (37°F), reaching a maximum of 17°C (63°F). Although January sees less precipitation at 70 mm (2.7 in) over 8 days, the humidity is notably higher at 84%. For more details on January weather, visit Annapolis weather in January.
September and February present strikingly different weather conditions. In September, temperatures range from a comfortable minimum of 11°C (52°F) to a warm maximum of 32°C (90°F), with an average of 23°C (73°F). The month sees around 113 mm (4.5 inches) of precipitation over about 10 days, accompanied by a humidity level of 75%. In contrast, February experiences much colder weather, with temperatures dipping to a minimum of -13°C (10°F) and averaging just 5°C (40°F), peaking at 21°C (69°F). February also has a similar level of precipitation at 116 mm (4.6 inches), but over 12 days, and it boasts a higher humidity of 83%. For a closer look at February weather, check out Annapolis weather in February.
September and March present contrasting weather patterns, with September experiencing warmer temperatures ranging from a minimum of 11°C (52°F) to a maximum of 32°C (90°F), while March sees much cooler conditions with temperatures dipping as low as -5°C (23°F) and peaking at 24°C (76°F). Both months have similar precipitation levels, with September receiving about 113 mm (4.5 in) and March slightly less at 95 mm (3.7 in), but the likelihood of rain is consistent, occurring on approximately 10 days in each month. Additionally, humidity levels in March are higher at 83%, compared to 75% in September, making March feel more damp despite the cooler temperatures. For more detailed insights on March weather patterns, check Annapolis weather in March.
In comparing the weather of September and April, it’s clear that September offers warmer temperatures with an average of 23°C (73°F) and maximums reaching up to 32°C (90°F), while April's average is significantly cooler at 13°C (56°F), peaking at 27°C (82°F). Both months experience similar levels of precipitation, with September receiving 113 mm (4.5 in) over about 10 days and April at 110 mm (4.3 in) across 11 days. Humidity levels are slightly higher in April at 81%, compared to September's 75%, indicating a bit more moisture in the air during the spring season. For more detailed insights, you can check Annapolis weather in April.
September and May exhibit distinct weather characteristics, making them unique months in their own right. In September, temperatures range from a minimum of 11°C (52°F) to a maximum of 32°C (90°F), with an average of 23°C (73°F). The month experiences moderate precipitation of 113 mm (4.5 in) across about 10 days, with humidity levels hovering around 75%. Conversely, May tends to be cooler, with minimum temperatures of 4°C (39°F) and maximums reaching 31°C (88°F), averaging 18°C (65°F). Rainfall is slightly higher in May, totaling 138 mm (5.4 in) over approximately 13 days, accompanied by a higher humidity level of 78%. To explore more about the weather during this month, you can visit Annapolis weather in May.
When comparing the weather in September to that in June, notable similarities and differences emerge. Both months experience high temperatures, with maximums reaching 32°C (90°F in September and 91°F in June), but September tends to be slightly warmer overall, with an average temperature of 23°C (73°F) compared to June's 24°C (75°F). Precipitation is relatively high in both months, with September receiving 113 mm (4.5 in) over approximately 10 days, while June sees a bit less at 102 mm (4.0 in) over 13 days. Humidity levels are also comparable, with September at 75% and June slightly higher at 79%. For more specific details, you can check out Annapolis weather in June.
In comparing the weather of September to July, we see notable differences in both temperature and precipitation patterns. September experiences a wider range of temperatures, with a minimum of 11°C (52°F) and a maximum of 32°C (90°F), averaging around 23°C (73°F). In contrast, July tends to be warmer overall, with minimum temperatures around 19°C (66°F) and maximums reaching up to 35°C (95°F), averaging 27°C (81°F). Additionally, September has heavier rainfall, totaling 113 mm (4.5 in) over 10 days, while July sees even more significant precipitation at 174 mm (6.9 in) across 14 days. Humidity levels remain similar in both months, with September at 75% and July slightly lower at 74%. For a more detailed look at July's weather, you can visit Annapolis weather in July.
In comparing the weather of September and August, September tends to be slightly cooler with average temperatures ranging from a minimum of 11°C (52°F) to a maximum of 32°C (90°F) compared to August's higher minimum of 17°C (63°F) and maximum of 33°C (92°F). Additionally, September experiences more rainfall, with precipitation measuring 113 mm (4.5 in) over 10 days, while August sees a higher total of 159 mm (6.3 in) over 15 days. Humidity levels remain relatively close, with September at 75% and August at 72%. For more details on August conditions, you can check Annapolis weather in August.
As September transitions into October, the weather experiences a notable shift. September boasts warmer temperatures, with an average of 23°C (73°F) and a maximum of 32°C (90°F), while October sees a drop in the average to 17°C (64°F) and a minimum of 5°C (41°F). Despite both months sharing the same number of precipitation days, October records slightly higher rainfall at 127 mm (5.0 in) compared to September's 113 mm (4.5 in). Additionally, humidity levels rise from 75% in September to 81% in October, contributing to a more damp feeling in the air. For more detailed information about October's weather in Annapolis, check out Annapolis weather in October.
September weather brings warm temperatures, with lows around 11°C (52°F) and highs peaking at 32°C (90°F), making it a month characterized by pleasant, summery days. In contrast, November experiences a significant drop in temperatures, with a minimum of -3°C (27°F) and an average of 9°C (49°F), as the cooler fall season sets in. Both months have notable humidity, with September at 75% and November slightly higher at 85%. While September sees around 113 mm of precipitation over 10 days, November has relatively less rain at 86 mm across 8 days. For more detailed information on November weather, you can visit Annapolis weather in November.
In September, the weather is warm and pleasant, with average temperatures around 23°C (73°F) and maximum highs reaching up to 32°C (90°F). Humidity is relatively high at 75%, and the month sees about 113 mm (4.5 in) of precipitation over 10 days. In contrast, December brings much colder temperatures, with an average of just 5°C (42°F) and lows dropping to -8°C (17°F). Despite having similar precipitation levels of 109 mm (4.3 in) over 10 days, December experiences higher humidity at 84%. For more details on December weather, check out Annapolis weather in December.
As summer transitions to autumn, September in Annapolis showcases a delightful blend of warm temperatures and increased humidity, distinct from the sweltering heat of July and August. With an average temperature that invites outdoor activities, the month also brings a few rainy days, contributing to its higher precipitation levels compared to the drier months of spring. The pleasant balance of warmth and occasional showers sets September apart, making it a prime time to explore the beauty of the city before the cooler fall air takes hold. To learn more about the full spectrum of weather dynamics in Annapolis, check out Annapolis Climate.