Winters in Yverdon-les-Bains are cold and snowy, with temperatures often dropping below freezing point. January is the coldest month, with average lows around -1°C and occasional drops as low as -27°C. Spring arrives slowly, with March and April bringing mild temperatures, but still quite chilly at night. Summer months, from June to August, bring warm and pleasant weather, with highs often reaching 30°C. Autumn is a transition period, with temperatures gradually cooling down, but still relatively mild compared to winter.