From Newsweek · · 3m
Heat dome scorches 12 US states with record temperatures
A powerful heat dome is bringing dangerous, record-challenging temperatures and extreme humidity to over 40 million people across the south-central and mid-South US starting September 16.
In brief
A powerful heat dome is bringing dangerous, record-challenging temperatures and extreme humidity to over 40 million people across the south-central and mid-South US starting September 16. A heat dome traps hot air over a region, and when combined with high humidity that prevents sweat evaporation, it becomes…
Quick answers
- What is a heat dome?
- A heat dome forms when a large area of high pressure becomes stuck over a region, trapping hot air near the ground. Clear skies and bright sunshine keep temperatures rising day after day, and these patterns can move slowly, allowing heat to accumulate for weeks.
- What is the key takeaway from Heat dome scorches 12 US states with record temperatures?
- A heat dome traps hot air over a region, and when combined with high humidity that prevents sweat evaporation, it becomes life-threatening, especially for older adults, children, outdoor workers, and people with existing health conditions.
Heat dome hits 12 states
A powerful heat dome is bearing down on the south-central and mid-South US starting September 16, bringing record-challenging temperatures and dangerous humidity to at least 12 states.
40 million face heat risk
Over 40 million people are projected to face at least moderate risk of heat-related impacts on Wednesday, with 26 million under extreme risk, according to NOAA meteorologists.
“Over 40 million people are projected to face at least a Moderate risk of heat-related impacts on Wednesday, with 26 million under Extreme risk.”
Dallas breaks heat records
The Dallas-Fort Worth metroplex is experiencing unseasonably warm overnight temperatures alongside a historic multi-week stretch of heat, achieving its highest 30-day average high temperature on record.
“The Dallas-Fort Worth metroplex is experiencing unseasonably warm overnight minimum temperatures alongside a historic multi-week stretch of heat.”
Temperatures reach 110 degrees
Areas in and around central Mississippi, southeast Arkansas, and northeast Louisiana should brace for temperatures up to 110 degrees. Heat index values in Oklahoma could reach 107 degrees, while Texarkana could see highs near 109 degrees.
What is a heat dome?
A heat dome forms when a large area of high pressure becomes stuck over a region, trapping hot air near the ground. Clear skies and bright sunshine keep temperatures rising day after day, and these patterns can move slowly, allowing heat to accumulate for weeks.
Humidity makes heat deadly
High humidity makes a heat dome more hazardous because it limits sweat evaporation, one of the body's main ways to cool itself. When air temperatures reach around 95 degrees, the body becomes increasingly dependent on sweat evaporation to release heat.
Heat kills 1,220 Americans yearly
Heat waves are among the leading causes of weather-related deaths in the United States. The CDC estimates that extreme heat kills approximately 1,220 people in the US each year, with heat exposure leading to heat exhaustion, heatstroke, cardiovascular complications, kidney failure, and electrolyte imbalances.
“Heat waves are among the leading causes of weather-related deaths in the United States.”
Vulnerable groups face highest risk
Older adults, children, pregnant women, outdoor workers, athletes, and people with existing heart or lung conditions are the most vulnerable to extreme heat and face the highest risks of heat-related illness.
How to stay safe in extreme heat
Stay in an air-conditioned building or use a public cooling center. Drink water regularly, wear light and loose-fitting clothing, and move intense outdoor activity to early morning or evening. Check on older relatives and neighbors, and never leave children or animals in parked vehicles.
Heatstroke is a medical emergency
Confusion, fainting, loss of consciousness, or an extremely high body temperature are signs of heatstroke, which is a medical emergency. Anyone experiencing these symptoms should be moved to a cooler location while emergency services are called immediately.
The takeaway
A heat dome traps hot air over a region, and when combined with high humidity that prevents sweat evaporation, it becomes life-threatening, especially for older adults, children, outdoor workers, and people with existing health conditions.
