Friday, June 25th 2021, 9:20 am - This feature will be particularly perilous because it's so rare in this part of the world. Sixty per cent of British Columbians do not own an air conditioner in their households.
Editor's note: This article is no longer be updated. Click here for the latest on the potential life-threatening heat wave impacting Western Canada.
A heat dome usually camps in the Four Corners section of the southwestern United States; instead, it will bubble up directly over British Columbia by Saturday -- extending into the northern territories and Alberta.
This feature will be particularly perilous because it's so rare in this part of the world. Sixty per cent of British Columbians do not own an air conditioner in their households.
A heat dome is colloquially known as an intense high-pressure system that features descending air that compresses and warms to record levels at the surface.
These features tend to be cloudless, as well; this setup is an excellent inhibitor for vertical motion that produces clouds in the atmosphere. Heat domes often sniff out regions in drought, and as the old saying goes, drought breeds drought.
Then you get a feedback effect. The warm air gets trapped in the lower elevations, and temperatures can only fall into the 20s at night. The following days can be incrementally toastier.
These are the antecedent conditions that can cause all-time heat records to crumble.
After building off the Pacific, the core of the heat dome is over Vancouver Island, but the warmest temperatures will lag.
Temperatures across the South Coast, away from the water, spill into the low 30s, with pockets of mid-30s speckled across the southern Interior.
Muggy along the coast with dew points visiting the upper teens, making it feel in the upper 30s.
The core of the heat dome is over the South Coast and southern B.C.
Temperatures push into the mid-30s across inland sections of the South coast, with even the occasional upper-30 reading in Port Alberni, Abbotsford, and throughout the southern Interior.
Potentially the warmest day in history for some cities in the B.C.
Record-maximum overnight lows, record daytime highs, record humidex values – it's all converging towards an extreme weather event. The ridge has surged so far north that some locations in the N.W.T. have the chance to reach the upper 30s for daytime highs near the Alberta border.
Temperatures in the Interior can soar well into the low 40s for daytime highs. The warmest temperature recorded in June will probably fall -- a whopping 42°C in Hedley during a 2015 heat wave in the province.
A thermal trough, a thin, weak area of low pressure, tends to develop along the coast during these heat events, enhancing the offshore flow and allowing the air to further warm as it snakes down from the coastal mountains.
WATCH BELOW: THIS PART OF B.C. WILL BE HOTTER THAN THE REST
Sunday morning and Monday morning will be warmer than the average daytime high for the end of June - bottoming out as high as 23°C, or even 24°C for some.
For some relief, head down to the Pacific Ocean, but it remains to be seen if the daytime sea-breeze will push very far inland, at all. Your best bet is to be directly in the ocean, or somehow find your way to Prince Rupert.
It's looking likely that the dangerous heat wave will spill into early next week. The heat will also spread into Alberta and Saskatchewan, with daytime temperatures pushing the mid-to-upper 30s by Tuesday.