Castilla–La Mancha has a continentalised Mediterranean climate: a Mediterranean climate with a marked character of a continental climate. The continentalised Mediterranean climate is like a typical Mediterranean climate, but with more extreme temperatures typical of a continental climate. Lack of a marine influence leads to much more extreme temperatures: hotter summers and quite cold winters, with a daily oscillation of 18.5 °C (33.3 °F). Summer is the driest season, with temperatures often exceeding 30 °C (86 °F), sometimes reaching and exceeding 35 °C (95 °F). In winter, temperatures often drop below 0 °C (32 °F), producing frosts on clear nights, and occasional snow on cloudy nights.

Castilla–La Mancha is part of what has traditionally been called España Seca (“Dry Spain”). It receives relatively scarce precipitation, much as in a typical Mediterranean climate. Precipitation presents a notable gradient from the centre of the region, where it does not surpass 400 millimetres (16 in) per year, to the mountains where it can exceed 1,000 millimetres (39 in) per year, on the slopes of the Sierra de Gredos and the Serranía de Cuenca. The greater part of the region has less than 600 millimetres (24 in) of rain annually. The driest part of the region is along the Albacete-Hellín axis, with less than 360 millimetres (14 in) per year.