Planning for the weather is a good way to make your trip to Harrington Harbour relaxing and enjoyable, especially when you’re splurging. The hottest months are usually August and July, with an average temperature of 14°C, while the coldest months are February and January, with an average of -7°C. The snowiest months in Harrington Harbour are January, February, March and April, with each month seeing an average of 124 cm of snowfall.