However , the summers are short ; no more than three months of the year ( but at least one month ) must have a 24-hour average temperature of at least 10 ° C ( 50 ° F ) to fall into this category of climate .
However , the summers are short ; no more than three months of the year ( but at least one month ) and must have a 24-hour average temperature of at least 10 ° C ( 50 ° F ) to fall into this category of climate .