Extreme heat can be dangerous. So when the Weather Service issues a heat alert, it’s important to know what to do.
Heat alerts are based on the heat index — a combination of temperature and humidity.
When the weather is both hot and humid, your body can struggle to cool down — which increases the risk of emergencies like heat stress or heat stroke.
So to warn people when dangerously hot conditions are possible in the next few days, the National Weather Service will issue an excessive heat watch.
This allows you to plan ahead — for example by finding a cooling center if you do not have air conditioning or figuring out how to get to work without walking or biking.
Then when the Weather Service issues a heat advisory or excessive heat warning, you can put these plans into action.
A heat advisory means a heat wave is forecast within the next 12 hours. And an excessive heat warning — the most severe alert — means those conditions are expected to be especially dangerous.
When this happens, it’s critical to stay hydrated and out of the sun, and in an air-conditioned building if possible.
As the climate warms, extreme heat is becoming more common. But by paying attention to heat alerts, you can stay safe and healthy.
Reporting credit: Ethan Freedman / ChavoBart Digital Media
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