Lake Ladoga is located in the moderate zone of the northern
hemisphere stretching from 40o to 65o northern latitude.
Annual solar radiation in the Lake Ladoga drainage area is 290-420
KJ.cm-2. The climate is formed under the influence of marine air from the Atlantic, continental air from the moderate latitudes and frequent invasions of the Arctic air. The lake itself also produces considerable effect on the climatic conditions.
The weather in the Lake Ladoga area depends mainly on the cyclonic activity which intensifies the exchange of warm and cold air masses, and on the moisture brought to the continent from the oceans. Air masses coming from the Atlantic carry heavy snowfalls and thaws in the winter, and rainy and windy weather in the summer.
Extreme values of climatic characteristics are smoothed down in the Lake Ladoga system, so the continental air masses passing over the lake aquire some characteristics typical for marine air.
Mean air temperature in the Lake Ladoga area through 1881-1960
was +3.2oC. The mean temperature of the coldest month (February) is
-8.8oC, of the warmest month (July) - +16.3oC. The lake
is normally covered in ice from February to May.
Mean annual precipitation in the same period was 475 mm. The least precipitation is recorded in February-March (24 mm/month), the greatest - in September (58 mm/month).
Ladoga shore is the warmest area in the Republic where winters are mild. It is noted for the long growing and frost-free periods.
Mean air temperature in January ranges from -8 to
-10oC, in July - about 16oC. Frost-free period lasts
120-130 days, the number of snow-cover days varies from 135 to 145. Annual
precipitation is 650 mm, of which 200 mm fall during the growing period.