IMD Monsoon Alert System: What Each Colour Means

The India Meteorological Department (IMD) uses a four-color alert system—Green, Yellow, Orange, and Red—to communicate the severity of weather events like monsoon rains, storms, and cyclones. These alerts help both the public and disaster management authorities take timely action.

1. Green Alert – No Advisory

• Meaning: Normal or mild weather expected, with little to no rain.
• Rainfall Range: Typically less than 64 mm in 24 hours.
• What to Do: No special precautions needed; normal activities can continue.

2. Yellow Alert – Be Aware

• Meaning: Possibility of moderate rainfall and minor disruptions.
• Rainfall Range: Approximately 64.5 mm to 115.5 mm in 24 hours.
• What to Do: Stay alert; carry rain gear, avoid water-logged areas, and monitor local forecasts.

3. Orange Alert – Be Prepared

• Meaning: Heavy to very heavy rainfall is likely; potential for significant impact.
• Rainfall Range: Approximately 115.6 mm to 204.4 mm in 24 hours.
• What to Do: Prepare for possible power outages, waterlogging, transport disruptions, and localized flooding. Limit outdoor movement if possible.

4. Red Alert – Take Action

• Meaning: Extremely heavy rainfall is expected, with a high risk to life and property.
• Rainfall Range: More than 204.5 mm in 24 hours.
• What to Do: Follow evacuation orders if issued, avoid all non-essential travel, and stay indoors. Emergency response teams may be mobilized.

Why These Alerts Matter

These alerts simplify complex weather data into easy-to-understand warnings that help people and governments take appropriate precautions. They’re based on rainfall intensity, but also consider wind speeds, lightning, flooding risk, and storm surge when applicable.

The IMD updates these alerts regularly during the monsoon season to help ensure timely response and risk reduction across affected regions.