(Bloomberg) -- A blanket of heavily polluted air covering much of the eastern US is likely to last until Tuesday, even as levels in New York City showed improvement. Washington DC issued a “very unhealthy” air-quality alert.

President Joe Biden said the US would “respond promptly” to any Canadian requests for more firefighters and air tankers.

There are almost 450 active fires in Canada, a number similar to Wednesday’s. Active blazes in Quebec dropped to 132 from about 150, according to the website of an organization that tracks fire activity in the area.

New York’s air quality returned to “moderate” for the first time since Monday. The region’s airports including LaGuardia and Newark faced delays for a second day due to low visibility, creating the risk of a ripple impact on US flights.

Key Stories:

  • Wildfire Smoke Spreads Haze Across US East, Threatening Flights
  • Heat, Dryness From Climate Change Make Wildfires Much Worse
  • Smoke-Less Offices Tout Air Quality to Get Workers to Show Up
  • New York’s Toxic Wildfire Smoke Is All Too Familiar to Asia 
  • Canada Wildfires Envelop Millions of North Americans in Smoke
  • Big Take: Wildfire Smoke Leaves Children Gasping for Air Years Later

Here’s the latest news: (All times are NY)

NYC’s Air Quality Returns to Moderate (2:40 a.m.)

New York City’s current air quality level is “moderate” as of 2 a.m. Eastern time, according to data from the New York Department of Environmental Conservation. That’s the first time since Monday that the city’s air quality has been at that level.

Northwell Sees Asthma Treatment Jump in NYC (4:45 p.m.)

Northwell Health, New York state’s largest health-care provider, saw a mild increase in respiratory illnesses Thursday, spokesman Matt Libassi said. The increase was more significant at Northwell’s locations in New York City. At Lenox Health Greenwich Village, for example, the number of asthma treatments were more than double the average, Libassi said.

Quebec Rain Not Expected Until Monday Night (4 p.m.)

The fire situation in Quebec is stable as winds have eased, but heavy rain is isn’t expected until Monday evening, Premier Francois Legault said at a news conference Thursday afternoon. The number of active forest fires in the province dropped to 132 from about 150, according to the website of a Quebec organization that tracks fire activity. Most are still blazing out of control in remote areas; about 13,500 people are under evacuation orders.

Northeast Solar Power Plunges by 50% (3:40 p.m)

A shroud of smoke has sent solar power generation in parts of the eastern US plummeting by more than 50% as wildfires rage in Canada. 

Solar farms powering New England were producing 56% less energy at times of peak demand compared with the week before, according to the region’s grid operator. Electricity generated by solar across the territory serviced by PJM Interconnection LLC, which spans Illinois to North Carolina, was down about 25% from the previous week.

Biden: US Will ‘Respond Promptly’ to Aid Requests (2:45 p.m.)

President Joe Biden said Thursday the US would “respond promptly” to any Canadian requests for firefighters and air tankers.

“Since May, more than 600 US firefighters, support personnel, and firefighting assets have been deployed, working alongside Canadian firefighters to tackle what is likely to be the worst fire season in Canadian history, and one that has huge impacts here in the United States,” Biden said in a statement.

The US president spoke with Canadian Prime Minister Justin Trudeau about the fires on Wednesday night. Biden also said he asked Transportation Secretary Pete Buttigieg to keep him briefed on flight delays caused by the smoke, while Environmental Protection Agency Administrator Michael Regan was monitoring air quality.

White House Delays Pride Event (1:30 p.m.)

The White House postponed until Saturday an event honoring Pride Month. Washington was among the areas worst affected Thursday, with the city under a Purple air quality alert, according to the Environmental Protection Agency’s tracking web site, AirNow.com. The White House cited the poor air quality in the region for the decision to move the event.

NYC Schools to Hold Remote Classes Friday (12:45 p.m.)

Belmont Park Cancels Races, Will Reopen Friday (11:05 a.m.)

The New York Racing Association canceled racing at Belmont Park on Thursday. NYRA plans to reopen the track Friday, a day before its biggest race of the year, the Belmont Stakes.

Nation’s Capital Under ‘Purple’ Alert (10:45 a.m.)

Washington DC, is under a “Code Purple” air quality alert Thursday, indicating “very unhealthy air conditions for the entire public,” according to the office of Mayor Muriel Bowser.

“Smoke from Canadian wildfires is causing unhealthy air quality in the Washington, DC, area and the northeast United States, and this problem is likely to continue or worsen through Friday,” Bowser’s office said in a statement Thursday.

Schumer Seeks More Help to Assist Canada (10:40 a.m.)

US Senate Majority Leader Chuck Schumer called on Agriculture Secretary Tom Vilsack to double the number of US Forest Service personnel who are helping to address the blazes in Canada.

Speaking on the Senate floor, Schumer said he would send a letter making the request later Thursday. The New York Democrat noted the high levels of pollution that have hit the East Coast and especially his home state, where schools are closing and outdoor activities are being canceled.

“These unprecedented wildfires are a crisis, for both Canada and the United States, so both nations must respond speedily and forcefully to contain the blazes,” Schumer said.

‘Extreme Risk’ Seen for Quebec, Ontario (9:52 a.m.)

Large parts of northwestern Quebec, northeastern Ontario and southern Ontario are still at “extreme” risk of fire, the country’s natural resources department said.

Air quality has improved significantly in Ottawa, where smoke had been at extreme levels on Wednesday. In Toronto, the morning skies are hazy, with the city’s air quality health index at 8 on a scale of 10, considered “high risk.” The city’s main school board has canceled all outdoor activities including athletic events and field trips.

Northwell Anticipates Illness Increase (8:15 a.m.)

Northwell Health, New York’s largest health-care provider, said there’s been a mild increase in asthma and wheezing cases but that there hasn’t been a significant jump in overall volume at its hospital emergency departments, according to spokesman Matt Libassi. 

At Northwell’s GoHealth urgent care centers in the New York City metropolitan area, Libassi said there’s been a slight increase in sore throats and eye-related complaints.

“We are anticipating an increase in respiratory illnesses and are stocking supplies accordingly,” he said.

Crisis Seen Lasting Until Tuesday (7:19 a.m.)

It will likely be Monday or Tuesday before the larger weather pattern that is pumping the smoke south from Canada starts to break up, according to Zack Taylor, a senior branch forecaster with the US Weather Prediction Center. There could be some minor improvement in New York Thursday as the worst of the smoke drifts more to the west. 

The plume itself covers most of North America. In the long-term, the only real solution will be if the fires in Canada are brought under control. 

NY Alerts to Last Through Midnight (7:15 a.m.)

Air quality alerts will remain in place across New York through midnight, said John Murray, a National Weather Service meteorologist in Upton, New York, on Long Island. 

“Unfortunately the smoke is to persist throughout the day and into this evening,” Murray said. “Winds are light, so there is not much opportunity for improvement.”

Flights to LaGuardia Grounded (7 a.m.)

The Federal Aviation Administration said departures to LaGuardia Airport are grounded on low visibility. The FAA said the probability of extension is medium, around 30%-60%.

Canada Blazes Lead World (6:48 a.m.)

As the smoke from Canada’s fires shroud New York City and beyond, data from NASA satellites shows the nation is leading the world in the number of blazes over the past 24 hours.

‘Hazardous’ Conditions in Philadelphia (3:51 a.m.)

“Hazardous” air lingered over Philadelphia early Thursday, according to the National Weather Service’s interactive map. New York continued to see “Unhealthy” to “Very Unhealthy” air quality, while the situation in the Washington, D.C. area was “Unhealthy.”

At Unhealthy levels, people who are active outdoors may start to experience some respiratory effects, according to the Environmental Protection Agency’s Air Quality Index. Hazardous conditions trigger emergency conditions.

Air Quality to Decrease in South (3:32 a.m.)

The National Weather Service has issued Air Quality Alerts for parts of the Great Lakes and Ohio Valley to the Northeast and Mid-Atlantic, it said in a statement. The impact of the fires has spread into the South, with the air quality in Alabama and Georgia set to decrease on Thursday.

Biden, Trudeau Speak (10:10 p.m. Wednesday)

President Joe Biden offered additional support to fight the wildfires burning in Canada during a call with Prime Minister Justin Trudeau, according to a readout of the conversation. The US has already deployed more than 600 firefighters and support personnel, and Biden directed his team to provide all available assets that can rapidly assist in suppressing the blazes.

Trudeau Says Climate Change to Blame (7:21 p.m.)

Trudeau made the comment after the call with President Biden. He added that hundreds of US firefighters have arrived in Canada, and more are on the way.

New York to Distribute N95 Masks (5:31 p.m)

 

--With assistance from Ari Natter, Skylar Woodhouse, Laura Litvan, Megan Scully, Caitlin Fichtel, David Papadopoulos, Mathieu Dion, Zachary Fleming, Brian K. Sullivan, Kevin Varley, Justin Sink, Madison Muller and Derek Decloet.

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