Helena's winters are long and chilly, with temperatures often plummeting below freezing from December to February, but occasionally rising into the mid-teens. Spring is a gradual warming process, with March marking a turning point as temperatures rise above freezing and stay that way through May. Summer brings warm days in June and July, with highs sometimes reaching the 30s Celsius, but evenings can still be cool. Autumn is similar to spring, with temperatures gradually cooling from September to November, before dropping again into winter. Overall, Helena's climate is quite cold and variable throughout the year.