ワルシャワ 9月の天気

Regulars describe a real split between two possible versions of this month - good sunny but cool days on one hand, multi-day stretches of rain when it does turn wet on the other - with a general cooling trend regulars place starting from the second week onward. Our row backs the mild average sitting between those extremes, 21.1C over 10.1C nights feeling 8C, with 57.6mm of rain across 9.6 days and a real 16.1 kph wind that regulars say makes the air feel colder than the number alone suggests. Layers and a proper jacket are the standard advice, with chilly mornings and evenings a near-constant even on an otherwise warm day. The record: humidity 73 percent, 8.3 hours of sun and AQI 47.

May sits inside the window regulars recommend for Poland generally - April through June, alongside September and October - for weather that is not too hot and not too cold, good for long walks through a city turning green. Our row backs the mild read at 20C over 8.3C, with 63.1mm of rain across 10.9 days, more of a passing shower than a soaking, and a trace of snow, 0.2cm, that most years will not see at all this late. The board's own preference sharpens toward the end of the month and into June, when the odds of a genuinely warm, settled stretch improve. The city itself feels noticeably livelier once the outdoor season opens. The record: humidity 65 percent, 11.4 hours of sun, a 16.9 kph wind and AQI 47.

Regulars give July here as usually pleasant at 20 to 25C, occasionally 30C or more, with heatwaves that rarely pass 35C and no real need for air conditioning - though it can turn humid. Our row's 26C over 14.5C is the middle of that. Their more useful point is comparative: July is less stable than August and can rain a good deal, with sunny heat building into afternoon and evening thunderstorms. Our 81.9mm across 13.3 days says rain falls on two days in five. Late July mornings can want a light jacket, so a rainproof layer and something warm are on the list. The record: humidity 68 percent, 11.6 hours of sun inside 16.2 of daylight, and AQI 51.

Warsaw-forum threads on August weather are consistent on one packing point: bring a proper rain jacket with a hood, not an umbrella - the city's August storms hit fast and the rain flies sideways once the wind picks up, and a flipped, shredded umbrella is a recurring complaint. Temperatures run warm, typically 18-28C with 30-plus days entirely possible, and humidity makes the warmer end feel heavier than the number alone suggests. It's also peak season: hotel rates jump 30-40 percent and Old Town gets genuinely busy, though a few posters say the city empties out a little as residents leave for their own holidays. The record: 26.1C days, 14.3C nights, 71mm of rain across nearly eleven days, 10.7 hours of sun and an AQI of 49.

Warsaw forum threads describe January as genuinely cold and unpredictable, typically ranging from about -6 to 3C but with posters warning real cold snaps can push it down toward -17C. The month's weather was called less predictable than nearby Prague's - the same week could bring +10C with heavy rain or -10C with heavy snow, or simply grey and foggy with no precipitation at all. A recurring theme across threads: Warsaw does have a winter air-quality problem, generally milder than some other Polish cities but still noticeable especially on still, windless days. The consistent advice was that proper cold-weather clothing makes the city entirely enjoyable regardless of which way a given January week goes.