Japan experiences extreme weather conditions, with the northernmost areas cloaked in snow throughout winter, and the southernmost islands of Okinawa warm all year long. In between, aside from Hokkaido, the rest of Japan has very hot and humid summers. August is the most uncomfortable month to visit unless you are planning to chill on a sheltered beach. Take precautions to avoid the dangers of heatstroke, sunburn, dehydration and insect bites (particularly mosquitoes). Outside the middle of summer, spring and autumn are pleasant, with warm, comfortable weather. June and early July, before the stickiness hits, is the rainy season, which sweeps across Japan from west to east. The extremes of winter differ depending on which part of the country you are in, and can be mild towards the south, and very cold if in the north or facing the chilly Sea of Japan. Weather forecasts are usually extremely accurate, and visitors can plan schedules well in advance. One final tip is that, if the forecast says rain, then expect rain. Unlike many countries, the rain may not relent, so a good, strong umbrella is recommended.