As in other northern countries, seasons vary widely in Estonia. The length of the longest day in summer is over 20 hours, while the shortest winter day lasts only six hours. It is not completely dark at night from the beginning of May until the end of July.

Due to the influence of the Atlantic Ocean and Gulf Stream, the weather in Estonia is considerably milder than the continental climate characteristic of the same latitude. The temperature in the summer months (June–September) is typically 15…18ºC; in winter, –4…–5ºC.

Temperatures can reach 30˚C (86˚F) in July and August. Summer is the best time to visit Estonia with many festivals, concerts and other activities taking place. 

Because the weather can change on a short notice, the organisers recommend the participants to backpack clothing for every kind of weather and raingear may also be useful.

You can check the forecasts for Tartu from the table on the  right.