Het weer in Krakau in september

Regulars describe a genuine Indian-summer stretch as typical for mid-month, mild and often sunny even as the calendar says early autumn, though the weather stays honestly changeable rather than a guaranteed run of good days. Our row backs that mild, still-showery read, 21C over 10C nights feeling 8C, with 96.3mm of rain across 11.9 days and humidity at 77 percent. Regulars are consistent this counts among the nicer months to visit overall, walking the Old Town and Wawel Castle comfortable in a light jacket, with the deep tourist crush of summer already thinning noticeably. A packable rain layer remains the standard advice given how often showers pass through. The record: 7.9 hours of sun, a 15 kph wind and AQI 53.

Regulars specifically prefer this month over June and July, when the heat turns hot and sticky with a real jump in thunderstorm risk - by contrast this month stays comfortable for walking Old Town or the riverside without the heat becoming tiring. Our row backs the mild, walkable read, 19.7C over 7.7C nights feeling 6C, with 79.4mm of rain across 13.1 days and a trace of very late snow, 0.1cm. Regulars are consistent that rain here rarely dominates a full day - more a passing shower between sunny or partly cloudy stretches, giving the city a fresh, green look rather than a washed-out one. A light jacket for the noticeably cooler evenings is standard advice. The record: humidity 72 percent, 10.3 hours of sun, a 15.8 kph wind and AQI 55.

July brings the crowds, the prices and the heat together - the busiest weeks of the Krakow year alongside Easter and Christmas - and regulars give the range as low twenties to low thirties, occasionally very hot, usually not humid. Our row sits at 26.2C over 14C at 72 percent. They add a piece of architecture as weather advice: the thick medieval stone keeps the interiors cool when the squares do not. July also tends to be wet, and our 98.6mm across 15.1 days agrees. Their alternative is May or June for weather, September or early October for the compromise. The record: 11.4 hours of sun inside 15.9 of daylight, a 15 kph wind and AQI 60.

August is the peak of the Krakow year in both senses. Regulars put mid-August between about 17C and 27C, with individual accounts ranging from 22 to 36, and warn that both July and August can throw flashes of genuinely unpleasant heat - our row's 26.2C over 14C is the average underneath that spread. Rain is not frequent but showers and thunderstorms are possible; our row records 96.4mm across 12.1 precipitation days, which is a lot of wet days for a month people picture as dry. On crowds they are blunt: this and July are the busiest, and September into early October is the swap they recommend for similar warmth with fewer people. The record: humidity 74 percent, 10.2 hours of sun and AQI 59.

Krakow forum threads describe January as genuinely gloomy, typically hovering around 0C with light drizzle keeping streets wet, but posters were clear the range can swing widely, from around -30C on an extreme cold snap to occasional readings near +10C. Winter air pollution was flagged as a real issue on still, windless days, and morning flights out of the local airport were noted as sometimes delayed or cancelled by thick fog. Despite the challenging weather, posters were genuinely positive about a January visit, several describing the city as built for winter - its character coming through in the cosy cafes and restaurants that make warming up after a snowy walk part of the experience rather than a compromise. The consistent advice was real layers, and posters noted January's quieter crowds as a real upside.