Monthly climate guide
Warsaw weather in September
Expect mild weather in Warsaw in September: afternoons reach about 21°C (69°F), while nights drop to around 10°C (50°F). Around 57 mm of rain falls over the month (some rain), and skies are often cloudy. Daytime highs are 5°C cooler than August and 7°C warmer than October.
What stands out in September
- Warsaw is usually about 2°C warmer than Olsztyn, 180 km away, in September.
- September brings early autumn to Warsaw.
- Good walking weather for combining Palace of Culture and Science and Old Town (Stare Miasto) in one day.
- Temperatures are falling — expect highs around 7°C lower by October.
Avg high
21°C
69°F
Avg low
10°C
50°F
Rainfall
57 mm
some rain
Humidity
72%
relative
Sky
63%
cloud · often cloudy
Warsaw weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 0°C / 31°F | -6°C / 22°F | 44 mm | 93% | 86% |
| February | 2°C / 35°F | -5°C / 23°F | 36 mm | 91% | 80% |
| March | 8°C / 46°F | -1°C / 29°F | 37 mm | 81% | 68% |
| April | 15°C / 58°F | 3°C / 38°F | 44 mm | 74% | 59% |
| May | 20°C / 67°F | 9°C / 48°F | 79 mm | 73% | 62% |
| June | 24°C / 74°F | 13°C / 55°F | 71 mm | 70% | 61% |
| July | 25°C / 77°F | 15°C / 58°F | 82 mm | 69% | 66% |
| August | 26°C / 79°F | 14°C / 58°F | 53 mm | 65% | 58% |
| September | 21°C / 69°F | 10°C / 50°F | 57 mm | 72% | 63% |
| October | 14°C / 57°F | 5°C / 41°F | 56 mm | 82% | 70% |
| November | 7°C / 44°F | 1°C / 34°F | 33 mm | 91% | 82% |
| December | 2°C / 36°F | -2°C / 28°F | 47 mm | 93% | 81% |
What to pack for September
- T-shirts plus a light layer for the evening
- Comfortable trainers or sandals for long walks
- A small travel umbrella, just in case
Is September a good time to visit Warsaw?
Our Warsaw guide recommends: May to September, when days are long and mild; July and August are the warmest months.
Try a milk bar (bar mleczny) — simple, traditional canteens serving pierogi and soups at very low prices.
Best time to visit Warsaw →Other Poland cities in September
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Warsaw weather in September. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/poland/warsaw/september
<a href="https://weathercompare.eu/weather/poland/warsaw/september">Warsaw weather in September</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/poland/warsaw" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="Warsaw weather in September"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/poland/warsaw/september">Warsaw weather in September</a> – WeatherCompare</p>
Warsaw in September: quick answers
Is September a good time to visit Warsaw?
Yes. September is one of the best months for Warsaw, with highs around 21°C and about 57 mm of rain.
How warm is Warsaw in September?
Average highs are about 21°C (69°F) and average lows about 10°C (50°F), based on 10 years of daily data.
Does it rain a lot in Warsaw in September?
Warsaw typically gets around 57 mm of rain in September — some rain.
When is the best time to visit Warsaw?
May to September, when days are long and mild; July and August are the warmest months.
Figures are long-term averages for the area around Warsaw (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.