DMV weather alert: Dangerous heat, poor air quality and severe storms across region

WASHINGTON, D.C. - If you are stepping outside this Sunday morning, you might notice the air feels exceptionally heavy. A combination of dense morning fog, low cloud cover, and residual smoke from holiday fireworks has triggered major air quality and heat advisories across the DMV region.

Air quality and heat

By the numbers:

Weather officials have issued two major alerts for the region on Sunday.

A purple air quality alert is currently in effect. The combination of stagnant humidity and leftover firework smoke has made the air very unhealthy. Anyone with breathing issues, lung disease, heart conditions, small children and the elderly are most at risk. The public is advised to avoid spending extended periods outside and avoid strenuous outdoor exercise.

An excessive heat advisory is also in effect until 8 p.m. Sunday. Temperatures will sit in the mid-90s across the region, but "feels'like" temperatures are expected to soar into the triple digits, peaking between 105 and 109 degrees from 3 to 6 p.m.

Severe storms

What we know:

The extreme heat and humidity are fueling severe instability in the atmosphere. A frontal system tracking to the north will spark a line of scattered, severe thunderstorms later on Sunday.

The storms will begin to the west in West Virginia around 3 p.m., pushing east across the Beltway between 4 and 5:30 p.m.

The region is under a slight risk of severe weather, with damaging winds and heavy downpours being the primary concerns. Expect scattered storms to persist through the evening before pulling out around 10 p.m.

Heat safety

What you can do:

With index values near 110 degrees, heat safety protocols are life-saving:

• Hydrate constantly: Drink water before you actually feel thirsty.
• Check on neighbors: Keep tabs on the elderly and those without reliable air conditioning.
• Never leave kids or pets in cars: Even with the windows cracked, temperatures inside a parked car can become lethal in a matter of minutes.
• Bring pets indoors: Dogs and cats cannot sweat to cool down like humans do. Leaving them outside in this heat can be fatal.

What's next:

Temperatures will finally cool down into the mid-80s starting Monday. However, the atmosphere remains highly unstable. Expect an unsettled weather pattern with a daily chance of showers and thunderstorms lasting all week long.