Powerful thunderstorms, flood threat after smoke surge in NYC, Tri-State: Live updates

Smoke from Canadian wildfires has once again blanketed New York City and the Tri-State, creating unhealthy air quality across much of the region Saturday morning as an AccuWeather Alert remains in effect.

Air quality reached an AQI of 173 early Saturday, a level considered unhealthy for everyone - not just people with asthma or other respiratory conditions. Thick smoke and haze reduced visibility across the area, with conditions expected to worsen through the morning before gradually improving later in the day.

Shifting winds will continue to push smoke across the region through midday, with air quality deteriorating in parts of Long Island and northern suburbs before the smoke begins to thin out. Residents are encouraged to limit prolonged time outdoors, avoid strenuous activities like running or exercising outside, and keep windows closed if possible.

The improvement in air quality, however, comes with a tradeoff.

Strong to severe thunderstorms are expected to develop later Saturday afternoon and continue through the evening as a cold front moves through the region. Storms could bring flooding downpours, damaging wind gusts and a few isolated tornadoes, prompting forecasters to urge residents to stay weather-aware. New Jersey, New York City and southern Westchester are under a flood watch ahead of the storms.

The first scattered showers are expected to develop during the afternoon, with the greatest risk for severe weather between about 4 p.m. and 9 p.m. The threat could linger until around midnight before the front clears the area.

The New York State Department of Environmental Conservation and Department of Health issued an updated Air Quality Health Advisory for fine particulate matter for Saturday.

The updated advisory is as follows:

The pollutant of concern is: Fine Particulate Matter

The advisory will be in effect: 12 a.m. until 11:59 p.m.

Gov. Kathy Hochul urged New Yorkers to remain vigilant even as air quality improved on Friday, stressing that conditions are expected to deteriorate again.

"While air quality has improved in portions of the State throughout Friday afternoon, lingering effects of smoke from Canadian wildfires continue to impact air quality into Saturday," Hochul said."We expect rain to bring some much-needed relief to New Yorkers experiencing poor air quality over the weekend, but with it we may see the possibility of severe storms, flooding and tornados. I remind everyone to take this weather seriously: Take precautions, know what to do if a storm reaches your areas and remember to stay air quality aware to protect your health. Stay informed by checking trusted sources for air quality and weather forecasts, and don't forget to check on friends and family members who might need assistance."

As the winds shifted Friday morning, blue skies tried to reclaim the city.

Lower temperatures and lower humidity made the streets more bearable, and New Yorkers are breathing a little easier.

But while the air quality index has dropped, it remains unhealthy for many residents. The elderly and those with chronic heart and lung conditions remain vulnerable to the tiny particles that still linger in the air.

The city's hospitals have not seen an increase in air quality-related illnesses. New York City Health Commissioner Dr. Alister Martin credits the use of masks for keeping the numbers low.

Emergency Management Commissioner Christina Farrell is hopeful the worst is over, but her staff is monitoring conditions and prepared to sound the alarm, if it comes to that.

And it's possible - as smoke is expected to increase again Friday night into Saturday.

N.J. Burkett has the details on the wildfire smoke lingering above New York City.

The Air Quality Index has dropped to 68 in New York City, putting it in the moderate category, but Lee Goldberg says smoky conditions will return Friday night and linger into Saturday.

Meteorologist Lee Goldberg has an update on the forecast and the current AQI level for New York City.