Currently in Los Angeles — August 18th 2022

The weather, currently.

Sunny and clear. Temperatures finally return to normal.

Finally, our high temperatures return to normal. Are you still sweating? Can you inhale a gulp of fresh, cool air? Will you set your alarm a little later, maybe as late as 10 o’clock, so you sleep in a little more, but also experience daylight before the temperature breaks 80°F?

It’s time to reset your circadian rhythm. No more scheduling around dawn and dusk. Today’s high of 86°F might as well be the first snow of winter. You’ve been expecting it, but you didn’t know when it arrive. That peak temperature won’t get here until the mid-afternoon, so you can also enjoy a long, slow, morning with minimal perspiration. The sky will be bright and mostly clear, and the winds will pick up once the highs settle in, so that will help you feel a little cooler. When the sun goes down and you can’t sleep because you’ve recently become nocturnal, know you’ll be tossing and turning in low temperatures around 67°F.

—Renée Reizman

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.”