September Weather in Johnson City, United States

Last updated: June 24, 2025

In Johnson City, United States, the average temperature in September is a pleasant 20°C (68°F). Expect a range of temperatures with a minimum of 5°C (42°F) and a maximum soaring to 31°C (88°F). This month typically brings 97 mm (3.8 in) of precipitation spread over 11 days, accompanied by an average humidity level of 68%. Enjoy the variability of the weather while exploring this beautiful location!

September Temperature in Johnson City

In September in Johnson City, the average temperature is 20°C (68°F). Maximum temperatures can reach 31°C (88°F), while minimums can drop as low as 5°C (42°F). This variation makes it a perfect time to explore Johnson City, so be sure to pack layers for your adventure!

September Weather in Johnson City: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Johnson City, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Johnson City, September typically has an average temperature of 20°C (68°F), with highs reaching up to 31°C (88°F) and lows dropping to around 5°C (42°F).
JanFebMarAprMayJunJulAugSepOctNovDec374347546369737168584541
Data source: Temperature data for Johnson City generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Johnson City

In Johnson City in September, the total precipitation amount is 97 mm (3.8 in) over the course of 11 days.

September Precipitation Trends in Johnson City

The chart displays monthly precipitation patterns in Johnson City, 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 Johnson City, September typically receives around 97 mm (3.8 inches) of precipitation spread over approximately 11 days.
JanFebMarAprMayJunJulAugSepOctNovDec951451291371221191021189712283125
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Johnson City

In Johnson City in September humidity is 68%. With an average temperature of 20°C (68°F), this humidity feels like a warm embrace, making it ideal for leisurely strolls while also prompting travelers to stay hydrated and seek out refreshing breaks from the heat.

September Average Humidity in Johnson City

This chart illustrates the average monthly humidity levels in Johnson City, 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 Johnson City is approximately 68%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec87%87%86%84%83%83%79%66%68%78%89%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Johnson City

In Johnson City in September, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Johnson City.

Maximum UV Index Levels in Johnson City for September

The chart shows the monthly maximum UV Index (UVI) for Johnson City 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 Johnson City typically reaches 10, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec468101111111010853
Data source: Johnson City 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 Johnson City Compares to Other Months

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

This table compares monthly weather conditions in Johnson City, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather3°C (37°F)95 mm (3.7 inches)87%moderate
February Weather6°C (43°F)145 mm (5.7 inches)87%high
March Weather8°C (47°F)129 mm (5.1 inches)86%very high
April Weather12°C (55°F)137 mm (5.4 inches)84%very high
May Weather17°C (64°F)122 mm (4.8 inches)83%extreme
June Weather20°C (69°F)118 mm (4.7 inches)83%extreme
July Weather23°C (73°F)102 mm (4.0 inches)79%extreme
August Weather22°C (71°F)118 mm (4.7 inches)66%very high
September Weather20°C (68°F)97 mm (3.8 inches)68%very high
October Weather15°C (59°F)122 mm (4.8 inches)78%very high
November Weather7°C (45°F)83 mm (3.3 inches)89%moderate
December Weather5°C (41°F)125 mm (4.9 inches)86%moderate

Compare Johnson City's Climate with Cities Worldwide