Poland’s climate is moderately warm, transitional. The weather varies, with summer averages between 16 and 20°C (60–68°F) and winter between -6 and 0°C (21–32°F). July is the warmest month, January is the coldest. Hot days, with a temperature of at least 25°C, occur in Poland from May to September. November is the cloudiest month, while the least cloud cover is in August and September.
If you come to Poland for a whole year, you should take with you both a warm down jacket, a hat, gloves, an umbrella and light clothes for the summer days.