September Weather in Warsaw, United States

Last updated: June 24, 2025

In September, the average temperature in Warsaw, United States is a pleasant 24°C (75°F). However, temperatures can fluctuate, with a minimum of 10°C (50°F) and a maximum reaching up to 35°C (95°F). Expect some rain, as precipitation averages 183 mm (7.2 in) over about 10 days, and the air will feel quite humid, with an average humidity level of 79%.

September Temperature in Warsaw

In September in Warsaw, the average temperature is 24°C (75°F). Maximums can reach 35°C (95°F) and minimums can be as low as 10°C (50°F). This makes Warsaw an ideal destination for travelers seeking warm weather along with the possibility of cooler evenings.

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

The chart illustrates September temperature patterns in Warsaw, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Warsaw, September typically has an average temperature of 24°C (75°F), with highs reaching up to 35°C (95°F) and lows dropping to around 10°C (50°F).

Data source: Temperature data for Warsaw generated using information from the Copernicus Climate Change Service.

September Precipitation in Warsaw

In Warsaw in September, the precipitation amount is 183 mm (7.2 in) over a duration of 10 days.

September Precipitation Trends in Warsaw

The chart displays monthly precipitation patterns in Warsaw, 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 Warsaw, September typically receives around 183 mm (7.2 inches) of precipitation spread over approximately 10 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Warsaw

In Warsaw in September, humidity is 79%. With an average temperature of 24°C (75°F), this humidity feels like a warm, tropical embrace, making traveling quite sticky and requiring ample hydration and light clothing to keep comfortable while exploring.

September Average Humidity in Warsaw

This chart illustrates the average monthly humidity levels in Warsaw, 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 Warsaw is approximately 79%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Warsaw

In Warsaw 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 Warsaw.

Maximum UV Index Levels in Warsaw for September

The chart shows the monthly maximum UV Index (UVI) for Warsaw 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 Warsaw typically reaches 9, which falls under the very high exposure category.

Data source: Warsaw 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 Warsaw Compares to Other Months

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

This table compares monthly weather conditions in Warsaw, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	7°C (46°F)	87 mm (3.4 inches)	85%	moderate
February Weather	10°C (51°F)	86 mm (3.4 inches)	82%	high
March Weather	12°C (55°F)	69 mm (2.7 inches)	81%	very high
April Weather	17°C (63°F)	94 mm (3.7 inches)	80%	very high
May Weather	22°C (72°F)	123 mm (4.8 inches)	81%	extreme
June Weather	25°C (77°F)	159 mm (6.3 inches)	81%	extreme
July Weather	27°C (80°F)	139 mm (5.5 inches)	81%	extreme
August Weather	26°C (79°F)	178 mm (7.0 inches)	80%	very high
September Weather	24°C (75°F)	183 mm (7.2 inches)	79%	very high
October Weather	19°C (67°F)	59 mm (2.3 inches)	80%	very high
November Weather	12°C (54°F)	83 mm (3.3 inches)	85%	moderate
December Weather	9°C (49°F)	111 mm (4.4 inches)	86%	moderate