An urgent public health warning has been issued for tens of thousands of Florida residents with federal officials anticipating dangerous air quality levels descending on the Tampa Bay area on Tuesday.

More than 50,000 seniors are being advised to stay indoors at the risk of contracting a serious illness, or worse.

The US Environmental Protection Agency (EPA) is forecasting air quality in the Tampa metro region to plunge into the ‘orange’ zone on the Air Quality Index (AQI), a level classified as ‘unhealthy for sensitive groups.’

Officials say for the more than 13 percent of Tampa’s population aged 65 and over, they should not step outside unless absolutely necessary.

Making things more dangerous is that it is not smog that can be seen in the air or like a wildfire that can be smelled on the breeze.

Instead it is a chemical soup of ozone and particulate pollution that infiltrates lungs, weakens immune systems, and worsens chronic conditions.

For Tampa’s most vulnerable, the consequences could be life-threatening.

According to the EPA, the orange AQI level (101–150) marks the point at which outdoor air becomes a threat to anyone with asthma, heart conditions, or other respiratory illnesses.