Safety guides › Reading the radar

What do the colors on weather radar mean?

Green is light rain. Red and purple mean heavy rain and possibly hail.

Radar shows how much the beam bounces back from rain, hail and snow. The colors follow the standard National Weather Service scale.

• Blue and green: light rain or snow.
• Yellow and orange: moderate to heavy rain.
• Red: very heavy rain, possible hail.
• Pink and purple: large hail is likely.

A hook-shaped curl at the back edge of a strong storm can mean rotation. Trust the warnings rather than trying to spot one yourself.

Source: National Weather Service. Reviewed 2026-10-07.

This guide is general safety information. When a warning is issued for your area, follow the instructions from the National Weather Service and local officials.

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