Rain symbol

How to read it

The present weather symbols come from the WMO’s table of weather codes, which NOAA’s JetStream school reproduces in full. In it, one dot is rain, not freezing, intermittent and slight; two dots side by side are continuous slight rain; three dots in a triangle moderate rain; and four heavy rain. The University of British Columbia’s course chart gives the same meanings from the WMO code, and the University of Wisconsin–Madison’s notes explain that the intensity is shown by repeating the symbol. The WMO plots these symbols in black, even on a coloured chart.

Also searched as: dot on a weather map, freezing rain symbol, rain shower symbol, three dots weather symbol, two dots weather symbol.

Freezing rain and showers

The dot changes meaning with what surrounds it. Inside a sideways S it is freezing rain; above a small open triangle pointing down, it is a rain shower. ! wx-chart-rain-intermittent | Intermittent rain | One dot: slight rain, falling on and off. ! wx-chart-rain-moderate | Moderate rain | Three dots in a triangle. ! wx-chart-rain-shower | Rain shower | A dot over a downward-pointing triangle. ! wx-chart-freezing-rain | Freezing rain | A dot in the loop of a sideways S.

Look-alikes

A comma is Drizzle symbol, not rain: the comma has a tail, the rain dot does not. An asterisk is Snow symbol. Shaded areas of precipitation on a forecast map are a different thing: NOAA’s JetStream says such areas have historically been shaded green whatever the type.