Drizzle is the name given to light rain. The drop size of drizzle is smaller than that of rain, about 0.5 mm (millimeters) in diameter.[1] [1]National Weather Service Observing Handbook No. 8, Aviation Weather Observations for Supplementary Aviation Weather Reporting Stations (SAWRS), Manual Observations, October 1996 This short article about weather can be made longer. You can help Wikipedia by adding to it.