Atmospheric rivers drench coastal B.C., triggering flood and avalanche risks

https://fed.brid.gy/r/https://globalnews.ca/news/11735968/atmospheric-rivers-drench-coastal-b-c-triggering-flood-avalanche-risks/

I just had a paper accepted on #AtmosphericRivers in # Antarctica (expect more on that later), this is a great piece on what they are and how they're observed

European aircraft to track ‘rivers in the sky’ blamed for flooding - https://giftarticle.ft.com/giftarticle/actions/redeem/df1f3e7f-6463-4616-85ca-49591fa9ec00 via @FT

Deadly #Floods Due to #Levee Failures Reflect Need for #Infrastructure Investment

Levees were never designed to handle extreme weather that is now more common due to climate change.

By Farshid Vahedifard, December 29, 2025

"In recent weeks, powerful #AtmosphericRiver storms have swept across #Washington, #Oregon and #California, unloading enormous amounts of rain. As rivers surged, they overtopped or breached multiple levees – those long, often unnoticed barriers holding #floodwaters back from homes and towns.

"Most of the time, levees don’t demand attention. They quietly do their job, year after year. But when storms intensify, levees suddenly matter in a very personal way. They can determine whether a neighborhood stays dry or ends up underwater.

"The damage in the West reflects a nationwide problem that has been building for decades. Across the U.S., levees are getting older while weather is getting more extreme. Many of these structures were never designed for the enormous responsibility they now carry.

"As a civil engineer at Tufts University, I study water infrastructure, including the vulnerability of levees and strategies for making them more resilient. My research also shows that when levees fail, the consequences don’t fall evenly on the population."

Read more:
https://truthout.org/articles/deadly-floods-due-to-levee-failures-reflect-need-for-infrastructure-investment/

#ClimateChange #AtmosphericRivers #ExtremeRain #Flooding #ExtremeFloods #WhenTheLeveeBreaks

2nd #AtmosphericRiver to flood #California with firehose of rain into Christmas

#HeavyRain and #flooding problems experienced in the #Northwest in recent weeks from atmospheric rivers will shift farther south into California through Christmas Day with major travel disruptions and safety concerns.

By Alex Sosnowski, AccuWeather senior meteorologist

Published Dec 21, 2025

"Two main atmospheric rivers will force copious amounts of #Pacific moisture into #California this week. Heavy rain with incidents of flooding, washouts and mudslides will expand and shift from north to south over the state, leading to travel disruptions at the very least and posing some risk to lives and property in extreme cases. The #SierraNevada will receive many feet of snow as freezing levels lower through the week and the region is affected by both atmospheric rivers.

"The storms are hitting at a busy time of the year, with many traveling short and long distances, running errands and planning outdoor activities.

"The first atmospheric river was already in progress and will continue to focus on Northern to Central California into Wednesday. A second atmospheric river is forecast to develop and concentrate on Central and Southern California from Tuesday night through Christmas Day. But even beyond Christmas, lingering moisture will lead to additional rounds of showers and mountain snow, according to AccuWeather.

"Through Wednesday, much of the #Sacramento Valley and the #SanFrancisco Bay region will receive 2-4 inches of rain with locally higher amounts. The anticipated rainfall for San Francisco in the stormy pattern into next weekend will bring from one to two times the historical average for December.

"On the west- and southwest-facing mountainsides of the Coast Ranges and the Sierra Nevada, 4-12 inches of rain will pour down with an AccuWeather Local StormMax™ of 20 inches.

"At times, multiple inches of rain can fall in a matter of hours, overwhelming storm drains and causing small streams and short rivers to quickly overflow their banks. As the ground becomes saturated, the risk of debris flows, road washouts and hillside collapses will increase substantially.

"From Tuesday night to early Friday, the second atmospheric river will spray rain of varying intensity throughout Central and Southern California.

"A general 4-6 inches of rain is forecast to fall on the Los Angeles basin. Downtown, L.A. had seven times its historical average monthly rainfall for November with 5.53 inches. While no rain has fallen so far in L.A. this month, from two to three times December's average rainfall of 2.48 inches may occur with the stormy pattern from Tuesday to Saturday.

"On the southwest-facing hillsides of the Transverse Ranges, 6-12 inches will pour down with an AccuWeather Local StormMax™ of 16 inches. Even in many desert areas of Southeastern California, between 0.25 of an inch to 1 inch of rain is expected to fall.

"Just as with the first atmospheric river up north, rain will be drenching, leading to rapid urban flooding and flooding of small streams and short-run rivers, along with mudslides, washouts and the potential for hillside slides in Southern California. "

Source:
https://www.accuweather.com/en/severe-weather/2nd-atmospheric-river-to-flood-california-with-firehose-of-rain-into-christmas/1846140

#ClimateChange #AtmosphericRivers #ExtremeWeather #ExtremeRain #Landslides #Flooding #ExtremeWx