Rain/Suspension

In the Fed rules any game that is called for weather or darkness when it has not reached the regulation length (4 1/2 or 5 innings) is technically "no game" and is replayed from the start.

State associations can adopt other game ending or suspended game procedures if they wish.

Ref NFHS Rules 4-2 Ending a Regulation Game
and 4-3 Called Game.

pilsner-
Thanks for the info. One follow up question...do you have any idea what the rationale is for restarting the game vs. picking up where it was left off?
I don't know the NCAA rules, but MLB certainly picks up games where they left off in these situations....

jb,

NCAA and MLB use the same criteria for determining what is a game of regulation length. (4 1/2 or 5)
A game can't be considered suspended if it hasn't reached that minimum. In both codes it is "No Game".

As to why those minimums exist; well, I don't know of any rationale in print but at the Major League level they don't issue rain checks if the game has progressed to or beyond the minimum.