A 'Rex block' is over most of Ontario. Here's what it'll do to the weather

A Rex block is developing in Ontario, and here’s what that means for the province’s weather for the rest of the week.

On Wednesday afternoon, Environment and Climate Change Canada tweeted that, throughout most of Ontario, an extended period of warm and dry conditions is expected because of this Rex block.

A Rex block, which the federal agency jokes “does not have anything to do with dinosaurs,” is a type of atmospheric blocking pattern.

“Basically, what the block is, if you have a strong, high-pressure system, which is currently over Ontario,and then we have a low-pressure system in the southeast U.S. and then we have a low-pressure system in the southeast U.S. And these are essentially at a strong war with each other, where one of them won’t budge,” Lucas Alexopoulos, an operational meteorologist at Environment Canada, told CTV News Toronto.

“So, they’re locked into place like this, causing a kind of stagnant weather pattern for the next week or so for most of Ontario.”

Northwestern Ontario is not really affected by the Rex Block, Alexopoulos said, so it’s getting “skimmed” by both weather systems.

“That’s why we down here in the south are just seeing nice, sunny, dry conditions,” Alexopoulos said.

Based on the Environment Canada's’s modelling, far northwestern Ontario is expected to be hit with strong winds, isolated thunderstorms and rain in the next few days.

The region could also potentially see its “first heat event of the season,” as Environment Canada says daytime temperatures could hit a high of nearly 30 C on Friday.

As for Toronto, the city is forecasted to have sunny and clear skies this weekend, hitting a high of 24 C on Sunday.