The reason of the preponderance of the summer rains lies in the western and northwestern Atlantic winds, which, in that season, have easy access far into the southeastern part of the Ukraine. These winds bring so much moisture into the Ukraine that almost two-thirds of the annual rainfall belongs to May, June and July. The month with the greatest amount of precipitation for the entire Ukraine is June. Only the Polissye, Northwestern Volhynia and the western part of the Kiev territory show the heaviest precipitation in July, since, in these regions of forests and swamps, evaporation is heaviest at this time of greatest heat. The summer rains of the Ukraine differ from those of Central or Western Europe in their heaviness. Only in the Western Ukraine are the summer rains of the type of gentle rains that are uniform for an entire country; in the south and east they appear as cloudbursts in heavy showers. In Samashcani, in Bessarabia, there have been times when 200 mm. of rain fell in a single day, in Korovintzi [97]in the Poltava region, 5 mm. in one minute. In the Pontian steppes all rain falls in the form of heavy showers. The water flows off quickly and evaporates rapidly, before it is able to thoroughly saturate the ground. Electric discharges and hailstorms occur in close connection with the summer rains, most frequently in June, less so in July and in May. They usually come from the southwest in the afternoon hours. Most of these storms originate in the Carpathian Mountains and reach Volhynia and Kiev, but do not cross the Dnieper. The Caucasus, too, has very many storms. Hailstorms are most frequent in Galicia and Volhynia and the western part of the Kiev regions; very rare in the southeast. In August the amount of rainfall slowly decreases; in September and October still more, and so it continues until December. January is the month of least rainfall for the entire Ukraine (only one-fourth of the June figure), and this circumstance is of particularly great significance for the southern and eastern parts of the Ukraine. For this reason the cover of snow in the Ukraine is much less than in Central Europe or Muscovy, besides which, it is often disturbed by snowstorms. The slight snow-cover melts down quickly in the spring, without saturating the soil well, and without requiring much warmth. This explains the rapid rise of heat in the Ukrainian spring. From January until the end of April the amount of rainfall again grows slowly but steadily, reaching its maximum in June.