Plovdiv has a humid subtropical climate with considerable humid continental influences. There are four distinct seasons with large temperature jumps between seasons.
Summer (mid-May to late September) is hot, moderately dry and sunny, with July and August having an average high of 33 °C (91 °F). Plovdiv sometimes experiences very hot days which are typical in the interior of the country. Summer nights are mild.
Autumn starts in late September; days are long and relatively warm in early autumn. The nights become chilly by September. The first frost usually occurs by November.
Winter is normally cold and snow is common. The average number of days with snow coverage in Plovdiv is 15. The average depth of snow coverage is 2 to 4 cm (1 to 2 in), and the maximum is normally 6 to 13 cm (2 to 5 in), but some winters coverage can reach 70 cm (28 in) or more. The average January temperature is −0.4 °C (31 °F).
Spring begins in March and is cooler than autumn. The frost season ends in March. The days are mild and relatively warm in mid-spring.
The average relative humidity is 73% and is highest in December at 86% and the lowest in August at 62%. The total precipitation is 540 mm (21.26 in) and is fairly evenly distributed throughout the year. The wettest months of the year are May and June, with an average precipitation of 66.2 mm (2.61 in), and the driest month is August, with an average precipitation of 31 mm (1.22 in).
Gentle winds (0 to 5 m/s) are predominant in the city with wind speeds of up to 1 m/s, representing 95% of all winds during the year. Mists are common in the cooler months, especially along the banks of the Maritsa. On average there are 33 days with mist during the year.