To prevent water splashing out of the funnel in Rain gauge, guess the height of the cylinder above the rain gauge.
A standard rain gauge has a funnel with a diameter of 20.3 cm while the measuring cylinder is of 12.5 cm in height. If rain intensity is beyond 12.5 cm, the classification for rainfall is “Very Heavy Rainfall”. Any rain water in excess of 12.5 cm overflows into an outer metal cylinder. This prevents loss of rain water which may otherwise occur through splashing out of the funnel or spilling. The height of 12.5 cm was determined as per the commonly recorded pattern of rainfall in 24 hours.