(Bloomberg) --

The US Northeast, including New York City, will continue to breathe in choking smoke from fires across eastern Canada for the next few days, raising health alarms across impacted areas. 

While there could be showers in New York on Thursday, the smoke will likely linger, said John Cristantello, a National Weather Service meteorologist. “Rain can only do so much,” he said. “The bigger factor is the magnitude of the smoke and the wildfires.”

Air quality alerts stretch across Quebec and Ontario, including Montreal, Toronto and Ottawa, and from New York and New England to South Carolina in the US.

New Jersey Governor Phil Murphy warned residents in his state to exercise caution outdoors, especially vulnerable individuals including the young, elderly and those with heart or lung disease. “Make no mistake, from the wildfires in Canada to those cropping up with increasing frequency and severity in our own backyard, these extreme weather events are tangible – and devastating – evidence of the intensifying climate crisis,” he said. New York schools have cancelled outdoor activities and Mayor Eric Adams urged residents to limit their time outside as the smoke from forest fires across Quebec continues to pour south. A thick plume is moving across New York state and headed for the city, said Tom Kines, a meteorologist at commercial-forecaster AccuWeather Inc. “Their air quality is going to get worse,” he said. “We have got at least three more days of this.”

While the main culprit is the fires raging across Quebec, a low pressure system stuck off Nova Scotia is providing the mechanism to pour that smoke south across eastern Ontario and into New York and the US East Coast, Bann said. Low pressure systems spin counter-clockwise in the Northern Hemisphere, which means the winds blow from north to south at the edge of the fires.

“Relief is not coming anytime soon,” said Richard Bann, a forecaster at the US Weather Prediction Center, an arm of the National Weather Service. “For the time being the Northeast US is in a position where it going to continue to ebb and flow with the thickness and intensity of the smoke.”

Watch: Smoke From Canadian Wildfires Spreads to NYC (Video)

Across Canada, as of Tuesday, 423 fires were raging, according to the Canadian Interagency Forest Fire Centre. In all 2,305 fires have consumed four million hectares across the country.Air quality in New York is hovering at unhealthy levels, according to IQAir, a pollution mapping tool. Currently the city’s air ranges up to 168 on its 0 to 500 scale having reached as high as 222 overnight. As bad as that is, Canada’s capital Ottawa has reached 471, meaning conditions are hazardous. Things were even worse in Kingston, Ontario to the south where readings hit 475 at 7 a.m.

In addition to the threat in Canada, dry conditions and high winds are keeping the fire threat high across the US Mid-Atlantic, Bann said. While fire warnings haven’t been posted yet, it might just be a matter of time, he added.In other weather news today: China: Sweltering temperatures across China are killing livestock and stretching power grids, an early heat wave that portends another summer of disruption for Asia’s industry and food supply.

India: India’s monsoon rains will likely start in 48 hours after a severe storm delayed the weather event vital for the economy.

Europe: The warm temperatures blanketing most of the Nordic region and the continent will last into next week, with below-normal levels dominating the south, according to forecaster Maxar Technologies. 

--With assistance from Marika Katanuma and Janine Phakdeetham.

(Adds updates throughout on duration of smoky skies)

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