There's nothing like an all-inclusive holiday in Toyama to revive you, especially when you know what kind of weather to expect. Here's some information to help you choose when to book: The hottest months are usually August and July, with an average temperature of 23°C, while the coldest months are January and February, with an average of 3°C. February and May are the driest months, while July and September are the rainiest months.