The climate is northern continental, with long winters and short summers. Winter begins in October and lasts often well into April. Snowcover is common from mid or late November to the latter half of March. Cloud cover and slate gray skies are typical between October and early February, when drier and sunnier days arrive. Mean January temperatures are 22°-25°F(-4°-6°C). The Gulfs of Finland and Riga only freeze over during the coldest winters.
In addition to being cold and snowy, winter months are characterized by shortened daylight, a result of Estonia's northern latitude (59°N). When days are at their shortest, daylight is present only between 9:30 a.m. and 3:00 p.m. Prevailing gray skies from November through January make daylight seem even more fleeting. The sun, when it shines, hugs the horizon, thus giving the impression that it is early morning or late afternoon even at midday.
It is often difficult to say exactly when winter ends and spring begins. After the Vernal Equinox (March 21), daylight increases dramatically. Most days in late March, April, and May are sunny. Daytime temperatures, however, may still remain in the 30°-45°F range into late April, and it is not safe to put winter clothing into storage until late May. Occasional snow flurries and light snow are possible even through May.
Summer in Estonia is a short, magical season. July and August temperatures are the warmest, averaging 67°-75°F (19°-24°C). Mornings are cooler and the late afternoon can warm up to the low-80â€™s. The surface water temperature in the Baltic Sea is from 60°-78°F (16°-26°C). The heaviest rains occur in July and August, but they are usually passing showers. During summer months, Estonia benefits from its northern latitude, with daylight extending long into evening hours and reappearing well before earliest risers are out of bed. From early June to mid-July, there is no real "nighttime."
The short autumn can start as early as late August and is generally cool and rainy.