Poland's climate is moderate continental with considerable maritime influence along the Baltic Coast at Northwest. As a result, the weather can be unpredictable in this part of the country.
Springs begin cold and windy in March, but become sunny. Summers are cool and sunny but can provide some hot peaks; it is also the rainiest season. July is the hottest month in Poland. September and October are still enjoyable, hot and sunny.
In winter you could find snow anywhere and it could stop all means of transport for several days. Temperatures in winter are cold, it reaches sometimes 0 degree Fahrenheit.
The climate in Poland varies a lot and can change from a day to another and from a year to another.
The climate in Lithuania is quite the same as in Poland. Between mid-November and mid-March temperatures barely rise above freezing, and summers bring temperatures of around 70 degrees Fahrenheit. As in Poland, summer is the rainiest season.
When to go
From mid-May to October is the nicest time to visit Poland and Lithuania in terms of weather. As this region of the world is still not so touristic the sites won't be too crowded, even in summer. Below are the average temperatures in Poland and in Lithuania.
Temperatures in Poland