The weather in Catania experiences Mediterranean climate leading to long, hot and dry summer and short, mild winter.
Summer: Summer season extends from the month of May till September. If you are planning for sightseeing, try to avoid October as most of the precipitation is concentrated in this month. This leads to late spring.
Winter: Winter extends from November till late February. Hence, if you are wondering as to when to visit Catania, this period will be ideal to enjoy the city tour. If you are an adventurous traveller and wish to experience activities like skiing, late January till early February will be a good season to visit Catania.
So, the best time to visit Catania is from November to March.