Istanbul weather in December

December in Istanbul brings cool, damp weather typical of early winter. Expect average highs of 11.4°C (53°F) and lows of 6.3°C (43°F). The city receives around 90mm of rainfall spread across roughly 13 rainy days, so waterproof gear is essential. Sunshine is limited to about 5.5 hours daily, creating grey, overcast conditions that give Istanbul a moody, atmospheric charm. The Bosphorus can feel particularly cold and windy.

Culturally, December is a quieter month for tourism. You'll avoid summer crowds, and the city takes on a local flavor as Istanbulites prepare for New Year celebrations. Christmas decorations appear in upscale districts, though Istanbul's Muslim-majority population means holiday festivities are more muted than in Western cities. The weather suits contemplative exploration—visiting mosques, museums, and bazaars becomes more enjoyable without peak-season throngs.

For travelers considering December 2026, this month works well if you prefer fewer tourists and lower accommodation prices. Pack layers and waterproof outerwear, and embrace indoor activities like hammam visits, covered bazaar shopping, and museum tours. The cooler temperatures make walking the city's hills less exhausting than summer months.