Theory 64/Water cycle/Onset phase
Rain Needs a Saturation Threshold
The claim
Precipitation begins above a threshold in the ratio of condensation to evaporation within a rising parcel, so warm humid air can hold more before raining.
01Mechanism
Cloud droplets must grow past a critical size; the ratio determines whether they do.
02Prediction
Onset should track the ratio.
03Refutation
Onset tracking humidity would remove condensation rate.