This value is 1 if it's raining or snowing, and 0 otherwise.
This represents the the time of day. At midnight, the value is 0, at noon it is 12, and then it goes up to 24 before wrapping back to 0, just like the hours on the clock.
This is based on the distance between the SFX and the camera.
The range is 0-1, the distance is converted in some unknown way.
It does not always work for all sources of effects. This is used by the beacon effect, so it definitely works there.
This value is set through the Special Attribute param field on weapons.
Based on the "Display Blood" setting.
-101
This value will be set to 1 when the effect is meant to end due to the source of the effect going away, for example when the SpawnOneShotFFX event ends and it has IsRestrictToDummyPoly enabled. The value is otherwise 0.