What to expect from upcoming heatwave on Vancouver Island

Vancouver Island residents should prepare for a stretch of hot weather.

This weekend, a strong ridge of high pressure continues to move into place and will deliver some record-breaking heat to Western Canada.

Daytime temperatures will jump into the 20s starting Friday and the hottest days look to be Saturday through Monday.

Then, the slow "cool down" begins and we should be back to seasonal by next weekend.

A special weather statement has been issued for the bulk of the island as well as much of the province and parts of the Prairies.

WHY HAS A HEAT WARNING NOT BEEN ISSUED?

When it comes to any type of weather warning being issued by Environment and Climate Change Canada, certain criteria have to be met.

In the case of heat, the daytime highs and overnight lows have to be in a certain range as well as staying in those ranges for two or more consecutive days.

In this case, let's look at Vancouver Island. For three-quarters of the island, as well as parts of the mainland, the daytime high has to be 29 C or warmer and the overnight lows must be 16 C or higher.

With that in mind, when we look at the island's weekend forecast, it’s the overnight lows that keep us from issuing a warning, as they’ll be in the 12 to 15 C range.

Will some areas hit these numbers? Most likely they will. But, will both the high and lows meet the marks for two days or more? Probably not – at least not enough places to meet the criteria to have the statement be elevated to a warning. 

You can see more about warning criteria on the Environment Canada website. 

(Environment Canada)

NO 'HEAT DOME'

Another thing to remember is, this is not a heat dome. It will be unseasonably warm, but this is nothing like what we saw a couple of years ago.

For one, that was later in the year and the high pressure system itself was different. It was bigger, stronger, more intense and had different features, like a cap on top of the ridge, which trapped the heat and also contributed to keeping it blocked and in place for a longer period of time.

So while we will break some records this weekend, it’s not the same type of event. That being said, every precaution we took then we have to take now because heat is heat.

If you’re working outside, take breaks when you can, drink plenty of water, don’t keep animals, kids, parents, grandparents, any being, in the car and use your common sense.

We also have to be aware that it’s going to get very dry, so don’t throw cigarette butts out the window, put out fires fully and be careful where you drive off road.

If you enjoy the heat, get excited. If heat isn’t something you’re a fan of, get prepared.