Hastings' Dictionary of the Bible (1898)
RAIN. The force of the various allusions to this subject cannot be apprehended without some knowledge of the natural conditions of Palestine. Rain falls very frequently during what we call the cold months, from November to April. Sometimes it rains powerfully for several days, with thunder and lightning and a strong wind. In the summer season, from May to October, the earth is parched, verdure is destroyed, and vegetation languishes.
The first rain after the summer drought usually falls in October, and is called the former or autumnal rain, because it precedes seed-time and prepares the earth for cultivation. The latter rain falls in April, just before harvest, and perfects the fruits of the earth. Deut 11:14; Hos 6:3; Joel 2:23. Storms after this time were regarded by the Jews as unseasonable, and even miraculous. Prov 26:1; 1 Sam 12:16-19. 6 inches, which is greater than that of almost any part of the United States. See Palestine.