Weather is probably a major factor when you plan your trip to Tomamae, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July with an average temp of 64°F, while the coldest months are January and February with an average of 27°F. The snowiest months in Tomamae are January, February, March, and December, with each month seeing an average of 30 inches of snowfall.