September Weather in Jacksonville, United States

Last updated: June 24, 2025

In September, the average temperature in Jacksonville, United States is a pleasant 25°C (77°F). However, temperatures can range from a cool 11°C (51°F) to a scorching 37°C (98°F). Be prepared for some rain, as the area typically receives 94 mm (3.7 in) of precipitation over about 7 days. With an average humidity of 71%, it’s essential to stay hydrated and enjoy the climate!

September Temperature in Jacksonville

In September in Jacksonville, the average temperature is 25°C (77°F). Maximum temperatures can reach 37°C (98°F), while minimums can drop as low as 11°C (51°F). Pack accordingly for a range of weather conditions during your travels.

September Weather in Jacksonville: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Jacksonville, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Jacksonville, September typically has an average temperature of 25°C (77°F), with highs reaching up to 37°C (98°F) and lows dropping to around 11°C (51°F).
JanFebMarAprMayJunJulAugSepOctNovDec434656627279828176655148
Data source: Temperature data for Jacksonville generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Jacksonville

In Jacksonville in September, the precipitation amount is 94 mm (3.7 in) over a span of 7 days.

September Precipitation Trends in Jacksonville

The chart displays monthly precipitation patterns in Jacksonville, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Jacksonville, September typically receives around 94 mm (3.7 inches) of precipitation spread over approximately 7 days.
JanFebMarAprMayJunJulAugSepOctNovDec921531591661651031061119410877152
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Jacksonville

In Jacksonville in September humidity is 71%. With an average temperature of 25°C (77°F), this humidity feels like a warm embrace, making outdoor exploration a bit sticky but still enjoyable, especially if you take breaks in shaded areas and stay hydrated.

September Average Humidity in Jacksonville

This chart illustrates the average monthly humidity levels in Jacksonville, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Jacksonville is approximately 71%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec84%83%81%81%83%83%81%74%71%76%84%88%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Jacksonville

In Jacksonville in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Jacksonville.

Maximum UV Index Levels in Jacksonville for September

The chart shows the monthly maximum UV Index (UVI) for Jacksonville in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Jacksonville typically reaches 9, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec46810111111109754
Data source: Jacksonville September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How September Weather in Jacksonville Compares to Other Months

Weather in Jacksonville varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Jacksonville, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Jacksonville, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather6°C (43°F)92 mm (3.6 inches)84%moderate
February Weather8°C (46°F)153 mm (6.0 inches)83%high
March Weather13°C (56°F)159 mm (6.3 inches)81%very high
April Weather16°C (62°F)166 mm (6.5 inches)81%very high
May Weather22°C (72°F)165 mm (6.5 inches)83%extreme
June Weather26°C (79°F)103 mm (4.0 inches)83%extreme
July Weather28°C (82°F)106 mm (4.2 inches)81%extreme
August Weather27°C (81°F)111 mm (4.4 inches)74%very high
September Weather25°C (77°F)94 mm (3.7 inches)71%very high
October Weather18°C (65°F)108 mm (4.3 inches)76%high
November Weather11°C (52°F)77 mm (3.0 inches)84%moderate
December Weather9°C (48°F)151 mm (6.0 inches)88%moderate

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