January is the coldest month of the year in Japan, but whether it is "too cold" depends on your tolerance and destination. In 2026, major cities like Tokyo, Osaka, and Kyoto are chilly but often brilliantly sunny, with daytime highs around 8°C to 10°C (46°F–50°F) and nights dipping near freezing. It rarely snows heavily in these cities, making it a "dry cold" that is manageable with a good coat and Uniqlo Heattech layers. However, if you head to Hokkaido or the Japan Alps (like Nagano), it is a winter wonderland with sub-zero temperatures and massive snowfall, which is perfect for 2026's booming ski tourism. For most 2026 travelers, January is actually a fantastic time to visit because the air is crisp, the crowds are thin after the New Year holiday, and the visibility for seeing Mount Fuji is at its absolute best due to the clear, dry winter skies.