@PitchBright

My buddy found his code from 1.4.7.

My config file had this:

rain {
I:RainDownConst=864000
I:RainDownRand=2592000
I:RainUpConst=1000
I:RainUpRand=71000
I:StormDownConst=144000
I:StormDownRand=1
I:StormUpConst=1000
I:StormUpRand=23000
}
Rain = deals with rains
Storm = deals with storms
Up = active
Down = inactive
Const = minimum time it rains for
Rand = maximum additional random time
--time that rain/storm is active or not is (Const + some random between 0 and Rand)

He commented:

The method was changing "updateWeatherBody" in World so the hardcoded numbers were configurable instead of hardcoded, as well as do some stuff in "wakeAllPlayers"/"areAllPlayersAsleep" in World for altering how sleeping changes weather (and how it resets the counter).