Mlada Boleslav's climate is characterized by cold winters with temperatures often below freezing, averaging around 0°C in January and February. Spring brings gradual warming, with March and April temperatures rising to an average of 4°C and 6°C respectively. Summer months, June to August, are warm but not hot, with average highs ranging from 20°C to 19°C. Autumn is mild, with September and October averaging around 15°C and 9°C, before cooling down again in November and December. The temperature fluctuations throughout the year create a relatively moderate climate overall.