Boyd’s Bible Dictionary:

The early rains of Palestine fall in October, in time for seeding; the later, in April, in time for fruits
May to October is the dry season (Deut. 11:14; Hos. 6:3; Joel 2:23).

Concise Bible Dictionary:

Palestine differed from Egypt in that its vegetation was dependent on the rain from heaven, instead of having to be watered from the river. Rain fell regularly except when God withheld it in chastisement (Deut. 11:11-17). We read of the “early rain” and the “latter rain.” The early rain was connected with the sowing of seed; the month Bul signifies “rain,” which agrees with about our October; and the latter rain in spring (about our February). By recent statistics the seasons appear to have somewhat altered, and most rain now falls from November to March inclusive. It is also judged that the cutting down of trees to make charcoal has affected the fall of rain in some districts.
The temperature is in degrees of Fahrenheit. The rain in inches. The rain fell at Jerusalem on 65 days only in the year, and at Tiberias on 67 only. The most prevalent winds during the year were West, South West, and North West. Jerusalem is about 2,500 feet above the Mediterranean Sea, and Tiberias about 652 below the sea. From the “ Quarterly Statements” of the Palestine Exploration Fund.