Weather

Microscopic particles from wildfire smoke can cause serious health problems for animals, sometimes causing more harm than in humans, experts say.

Choking smoke from wildfires burning in Canada continues to billow into the eastern U.S., where more than 100 million Americans will again experience "unhealthy" to even "hazardous" air quality levels.

Several sporting events have been postponed Wednesday because of concerns over hazardous air quality issues caused by smoke blanketing the skies across the Northeast.

Hawaii’s Kilauea volcano started to erupt early Wednesday morning, according to an alert released by the Hawaiian Volcano Observatory.

The people most at risk from wildfire smoke are individuals with lung disease, asthma, heart disease, older adults, children, and expectant mothers.

Air quality is considered unhealthy when the Air Quality Index reaches 100 or greater. Wednesday morning, Philadelphia’s AQI was 212.

The intense Canadian wildfires are blanketing the northeastern U.S. and parts of Eastern Canada, turning the sky yellowish gray and prompting warnings for vulnerable populations to stay inside.

The tiny particles are small enough to get past airway defenses and cause breathing problems. Here's a closer look at what's happening and some precautions for dealing with the haze.

Air molecules from the smoke in Earth's atmosphere cause light to scatter out most of the blue light, leaving the remaining red light to create a red glow on the moon. More red moons are likely as smoky skies continue.

Dangerous and potentially deadly heat will plague the U.S. territory of Puerto Rico this week, thanks in part to plumes of Saharan dust that are blowing across the Atlantic Ocean from Africa.