Q. In regards to schach being blown off the sukka by an uncommon wind, (see above question), what is considered a ruach sheino metzuya or uncommon wind? does it have to happen at least after a span of thirty days? How many times a year does it have to blow?

A. The Rov defines, ruach sheino metzuyo, not as a factor of how many time a year it occurs, but rather as the surprise and astonishment it creates on those who witness it unusual strength and unique damage it creates.

Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit’a