Kaunas weather in September

Forum posters describe December in Kaunas as capable of being very wintry, rainy and freezing, with temperatures typically hovering around 0C, though posters note a genuinely lucky sunny day is possible too. Posters consistently recommend thermal layers, a hat, scarf and gloves as standard preparation. Posters describe early December in some years as still more autumn-like than winter, with little or no snow yet, while days themselves are at their shortest of the year regardless. Posters generally recommend pairing a Kaunas visit with Vilnius, noting Christmas decorations typically go up ahead of the holidays and stay festive into early January. Posters generally rate December as cold and genuinely variable, workable with proper winter gear.

Kaunas forum regulars, drawing on the same regional conversation as Vilnius, call early June warm and pleasant, with typical readings “between 18°C-28°C,” though sometimes it's unexpectedly cold, sometimes hot year to year — genuine variability rather than a single reliable number. Summer overall gets rated the best season to visit, with the high 20s to low 30s not uncommon at the warmer end. Kaunas's own draw beyond the weather: Laisvės Alėja, the 1.6km pedestrianised main street, along with the Devil's Museum, the Čiurlionis art gallery, the 9th Fort and Pažaislis Monastery, plus riverside beaches reachable by bus or bike along the Nemunas. Our record: 23.8°C days, 14.1°C nights, 10.6 rain days and 12.7 hours of sun — warm and sunny, sitting in the middle of the “18-28°C, some years hotter” range forums describe.