Portsmouth's winters are mild, with temperatures rarely dropping below freezing and averaging around 4-6°C. As spring approaches, temperatures gradually rise, with March and April often seeing highs of up to 23°C. Summer brings warmth, with June and July frequently reaching highs of 27-30°C, while autumn is generally cooler, with October's average temperature of 13°C marking a return towards winter conditions. The coldest months are December, January, and February, while the warmest months are June, July, and August.