Israel would never attack if everyone were expecting them to do so this summer. They would rather wait until everyone thinks they have become peacefull and dropped their guards again. Knowing that Iran is about 2 years away from it's first bomb, Israel still has time to wait until next year, or even, the summer in another 2 years.
U.S. to defend Syrian rebels with airpower, including from Assad (Reuters)
from the article: A war in the summer?