Wildfires in southeastern Canada’s Nova Scotia province have damaged or destroyed 200 homes near Halifax while forcing more than 16,000 people to evacuate. Thick plumes of smoke are also finding their way into the northeastern United States.
The expansive fires in Nova Scotia are of unusual intensity for the region, fueled by abnormally hot and dry weather. Some places have seen little to no rain this month, and much of the maritime zone was already abnormally dry as of late April.
Of the fires burning in Nova Scotia, the largest is over 24,700 acres (10,000 hectares) and is still out of control.
For comparison, in the past five years combined, 11,600 acres (4,700 hectares) burned in Nova Scotia, according to the province’s Department of Natural Resources and Renewables.
It’s just the latest fire emergency in Canada after historic conflagrations in the west over recent weeks.
Smoke is drifting into the northeastern U.S.
Smoke arriving in the United States from Canadian fires is nothing new. But usually it enters from the northwest, not the northeast. This week, unusual steering currents have developed.
The clockwise flow around a zone of high pressure anchored over New England and southern Quebec is directing the Nova Scotia smoke south and west. These steering winds are being enhanced by counterclockwise flow generated by low pressure off southeastern U.S. shores.
The smoke turned Tuesday’s sunrise in New York City hazier than normal.
Forecast models projected a thick plume to come ashore in southern New England on Tuesday, flowing through Cape Cod, Mass.; Boston; and Providence, R.I. The smoke may intensify Tuesday’s sunset and Wednesday’s sunrise through the urban corridor in the Northeast.
The amount of smoke is less than what was seen from fires in western Canada, but the source is considerably closer. Bostonians reported smelling the smoke Tuesday afternoon, and air-quality alerts were issued for parts of Massachusetts, southeast Pennsylvania and New Jersey into Wednesday.
A severe fire season so far
Canada is in the midst of a mega fire season, with many months to go. The 5 million acres (2 million hectares) scorched so far this year is not far from the annual average of 6 million acres (2.5 million hectares).
This year’s total has already surpassed totals from many previous years. For example, 2020 saw about 540,000 acres (220,000 hectares) burned.
While most of the blazes have blackened landscapes in the western provinces of British Columbia, Alberta and Saskatchewan, there have also been huge wildfires in Ontario, Quebec and the Northwest Territories in recent weeks.
Fire risk is well above average across most of the country, largely owing to widespread drier-than-normal conditions and elevated temperatures. One exception is Manitoba, nearer where the winter and spring storm track favored more-frequent precipitation.
A super-warm 2023
Most of Canada has seen above-average temperatures in 2023. Other than in a small portion of the south-central part of the country, most temperatures are running at least 3 to 5 degrees above average — which is large amount over nearly five months.
The warmth that dominated the eastern United States in the first several months of the year also frequently extended into eastern Canada. Since then, semi-permanent zones of high pressure have remained stuck in place. One high-pressure zone led to an extreme early-season heat dome in western Canada earlier this month, which intensified firestorms in the region.
Temperatures this week are expected to reach or surpass 86 degrees Fahrenheit (30 Celsius) in many parts of Ontario. Some locations such as Ottawa, Toronto and Windsor may flirt with 90 degrees (32 Celsius), readings more typical of the hottest part of summer.
Longer-term pattern signals suggest that there won’t be much change any time soon. This week’s pulse of heat will probably migrate west with time, increasing the fire risk once again.
Source: The Washington Post