Termiczne pory roku w rejonie Czes awic k. Na czowa (1963-2005)

The aim of the paper is to analyse variability of the dates of starts and lengths of the six thermic seasons in Czes awice and the surrounding region. In the analysed period (1963-2005) the biggest variability was characteristic of winter and early spring. Standard deviations of the dates of their starts amounted to 18 and 21 days - and of their lengths - 29 and 17 days. Spring and autumn was more stable - both in length and the dates of starts. The average length of that seasons was similar (57 and 58 days), which depends on the length of summer in an individual year. Summer was the longest season - on average, it starts at the end of May.