Weather conditions and temperatures vary across Japan's main island of Honshu.
Northern Honshu and the Japanese Alps experience cooler temperatures (avg temp: 0°C) and heavy snowfall during the winter months, whilst the southern and western regions have milder winters (avg temp: 4 - 5°C) but are prone to hot and humid summers, especially in the main cities of Tokyo, Kyoto and Osaka with temperatures pushing the mercury up to 35°C on some days.
June is the wettest month of the year across Honshu, with tropical showers occurring until early July.
In terms of temperature and weather conditions, spring and autumn are typically the most pleasant times of the year to visit Honshu. During April, the cherry blossom advances from Hiroshima, in the south, to the higher altitudes of Takayama and the Japan Alps by the end of the month; and conversely, the autumn colours work their way down from the mountains in early October to Kyoto and southern regions by late November.
Okinawa and Japan's southernmost islands enjoy a subtropical climate throughout the year, with temperatures that never dip below double figures, infact rarely dropping under 20°C.
During the winter months Okinawa experiences the country’s mildest temperatures, although sea temperatures are chilly and only the hardy venture into the water.
Come March, spring is definitely in the air, heralding the arrival of the famous cherry blossom, with Okinawa and the southern islands the first place to catch this much anticipated season. Although the months of May & June see tropical rain, it comes in the form of short, sharp bursts and conditions are good for diving.
Summer days are typified by high temperatures and maximum sunshine, making it a popular time to visit the region's beaches, although as summer progresses there's more chance of typhoon, with August and September being peak typhoon season.
Typhoon season passes as autumn progresses and autumn days are warm and dry.