Extreme Heat

The Houston area has very hot summers, and sometimes spring and fall temperatures reach dangerous levels as well.  Knowing heat safety and how to recognize heat-related illnesses can help save you or someone else. 

Heat Watch vs. Warning

Excessive Heat Warning - Take Action! An Excessive Heat Warning is issued within 12 hours of the onset of extremely dangerous heat conditions. The general rule of thumb for this Warning is when the maximum heat index temperature is expected to be 105° or higher for at least 2 days and night time air temperatures will not drop below 75°; however, these criteria vary across the country, especially for areas not used to extreme heat conditions. If you don't take precautions immediately when conditions are extreme, you may become seriously ill.

Excessive Heat Watches - Be Prepared! Heat watches are issued when conditions are favorable for an excessive heat event in the next 24 to 72 hours. A Watch is used when the risk of a heat wave has increased but its occurrence and timing is still uncertain.

Heat Advisory - Take Action! A Heat Advisory is issued within 12 hours of the onset of extremely dangerous heat conditions. The general rule of thumb for this Advisory is when the maximum heat index temperature is expected to be 100° or higher for at least 2 days, and night time air temperatures will not drop below 75°; however, these criteria vary across the country, especially for areas that are not used to dangerous heat conditions. Take precautions to avoid heat illness. If you don't take precautions, you may become seriously ill.

Heat Related Illnesses

During extremely hot and humid weather, your body's ability to cool itself is challenged. If the body cannot cool itself properly or if dehydration occurs, then body temperature can rise further which may cause a heat-related illness.