Currently in Toronto — August 18th 2022

Some sun, some cloud and maybe a thunderstorm

The weather, currently.

A familiar weather pattern continues into tomorrow. The GTA will remain under the influence of an upper-level low sitting south of us. Let's break it all down for you:

For starters, Thursday begins with bright skies and a wake-up temperature near 18°C. Once again, some clouds will start to build by early afternoon. This low-pressure system sitting to our southeast (over New England) will help generate some occasional showers and scattered thunderstorms. This will not be a widespread event. However, some of these storm cells from this system have previously delivered brief downpours in isolated areas.

Again, this will be very scattered, likely between 3:00 — 7:00 pm.

The high will be 28°C, which will seem like 31°C with the humidex. The wind will be light and the UV index will be 7 or high.

Thursday Night: Mainly clear with a low of 17°C.

Anwar Knight

What you need to know, currently.

Every winter, atmospheric rivers flow off the Pacific ocean towards California, many of them carrying more suspended water through the air than the largest terrestrial rivers on earth. In 1862 a series of atmospheric rivers proved disastrous for the Western United States, bringing catastrophic and unprecedented flooding to Oregon, California, and Nevada.

In 2010, scientists began a study they called the ArkStorm Scenario, named for the biblical flood, to account for the effect of climate change on these worst case scenarios floods.

According to the geologic record, these floods — caused by a quick succession of atmospheric rivers — occur every 150 to 200 years in California. A new study in Science Advances suggests that climate change has doubled the chances of this kind of catastrophic flooding occurring within the next four decades.

“The last time government agencies studied a hypothetical California megaflood, more than a decade ago, they estimated it could cause $725 billion in property damage and economic disruption,”  writes Raymond Zhong in the New York Times. “That was three times the projected fallout from a severe San Andreas Fault earthquake, and five times the economic damage from Hurricane Katrina, which left much of New Orleans underwater for weeks in 2005.”