It's shaping up as a trying weekend for Lower Mainlanders and others as a rash of advisories have been issued for heat and air quality during the next few days.

Environment Canada's original heat warning for the Lower Mainland and Fraser Valley this weekend—with temperatures in the low 30s due to a strengthening ridge of high pressure—has been upgraded to an extreme heat alert as of today (August 12), with daytime temperatures reaching as high as 35° C expected until Sunday.

Metro Vancouver also issued two air-quality advisories as of August 12: one for fine particulate matter due to outflow winds carrying smoke from wildfires in B.C. and Washington state to Metro Vancouver and the Fraser Valley Regional District (FVRD) and another for ground-level ozone in eastern Metro Vancouver and the FVRD.

In addition, the City of Vancouver has called a media briefing for Friday morning (August 13) to reveal additional cooling measures being put into place for residents after it escalated its heat response to Level 2. Staff from the park board, the Vancouver Public Library, and the Vancouver Emergency Management Agency will be present at the briefing.

More immediately, the city is opening an emergency cooling centre downtown on Thursday night (August 12) at Gathering Place (609 Helmcken Street), from 10 p.m. to 6 a.m. Friday morning (August 13). Working, reading, and sleeping spaces will be available, and well-behaved pets on leashes will be admitted if owners bring water bowls and waste bags.

Daytime city cooling centres established under the earlier, Level 1, heat alert remain, but with extended hours until 10 p.m. at the library's downtown central branch and at park board community centres. The Carnegie Community Centre, the Evelyne Saller Centre, and Gathering Place will stay open an extra hour, until 11 p.m. (Go here for city information on cooling centres, drinking-water fountains, and misting-station locations.)

The city will also be installing a "heavy" misting centre Friday (August 13) in the Downtown Eastside, at the intersection of Hastings and Abbott streets, from 11 a.m. to 8 p.m.

The criteria for declaring an extreme heat alert, as explained in an August 12 news release on behalf of medical health officers for both Fraser Health and Vancouver Coastal Health, were met by recording the temperature at 2 p.m. at both the Vancouver International Airport and Abbotsford, then averaging that with the next days maximum temperature.

"High temperatures in this range are historically associated with an increase in deaths among Lower Mainland residents," the release stated.

During the so-called heat dome extreme-temperature event that settled over the Lower Mainland between June 25 and July 1 earlier this summer, 808 sudden deaths were recorded in B.C., with 576 of those later attributed to the record-breaking heat.

"Based on previous heat events," the release noted, "the anticipated temperatures are proven to cause negative health outcomes among Lower Mainland residents who may not be acclimatized to temperatures in this range and may not have ready access to measures such as air conditioning. Heat stress can pose an immediate danger to health and may be fatal. Symptoms of severe heat-related illness can include dizziness, confusion, weakness and fainting or collapsing, including loss of consciousness."

The medical health officers advised Lower Mainlanders to take precautions against the heat, especially "the young, the elderly, those working or exercising in the heat, persons with chronic heart and lung conditions, some people with mental health conditions, people living alone and people experiencing homelessness or inadequate housing. If you are taking medication, ask your doctor or pharmacist if it increases your health risk in the heat and follow their recommendations."

Lower Mainland residents were also advised by authorities to regularly check on elderly and very young peope, those unable to properly care for themselves in extreme-heat situations, and all pets and other animals.