This is similar to the rain fall in London. The difference is that in London the distribution of the rainfall is over about 300 days of the year. In Jerusalem the distribution is about 30 days of the year. What rain Jerusalem receives comes almost all at once instead of scattered throughout the year. That accounts for the difference.
Temperatures There are areas where it snows and others where it is dismally hot.
It is possible, in this small area of land, to grow everything from pineapples and bananas to apples.