The coming California megastorm

[dalton99a]

https://www.nytimes.com/interactive/2022/08/12/climate/california-rain-storm.html
https://archive.ph/i6Wbq

The coming California megastorm
Aug. 13, 2022 at 10:26 am Updated Aug. 13, 2022 at 2:15 pm
By RAYMOND ZHONG

California, where earthquakes, droughts and wildfires have shaped life for generations, also faces the growing threat of another kind of calamity, one whose fury would be felt across the entire state.

This one will come from the sky.

According to new research, it will very likely take shape one winter in the Pacific, near Hawaii. No one knows exactly when, but from the vast expanse of tropical air around the Equator, atmospheric currents will pluck out a long tendril of water vapor and funnel it toward the West Coast. This vapor plume will be enormous, hundreds of miles wide and more than 1,200 miles long, and seething with ferocious winds. It will be carrying so much water that if you converted it all to liquid, its flow would be about 26 times what the Mississippi River discharges into the Gulf of Mexico at any given moment.

When this torpedo of moisture reaches California, it will crash into the mountains and be forced upward. This will cool its payload of vapor and kick off weeks and waves of rain and snow.

[Hugh_Lebowski]

1. Sooner the better (nt)

[wolfie001]

6. Is this an attempt at humor?

Not trying to be offensive, but the RW'ers have been hoping Cali falls into the ocean for decades and taking those 54 electoral votes with it.

[Zambero]

2. I drove I-5 through the CA central valley last month

Along with the triple-digit temperatures, it was a shock to see scores of dead and dying orchards along the way. This is the result of dropping water tables and an inadequate source of irrigation to sustain millions of acres of crops that receive little or no rain during the growing season. Known for its "benign" climate, California is actually a classic example of weather extremes that manifest themselves over extended periods of time. The rare periodic megastorm that visits the west coast may or may not happen any time soon, and climate change is another variable that could increase or decrease its frequency. At any rate, the dumping of 26 times the Mississippi River flow over an extended period would not the best circumstance for recharging the state's dwindling acquifer.

[MurrayDelph]

4. Several times a year,

I have to drive between Portland and Los Angeles. It's been disconcerting watching the degradation of what is now the Shasta Trickle and Shasta Pond.

My wife and I take slightly different routes for the Southern half of this drive; I frequently cut over to the 99 for the part began Sacramento and The Grapevine; it's flatter, I get better mileage (slightly lower speed limit means a slightly longer drive), and there are fewer right-wing billboards demanding Congress build "more dams" so they can have more farm water.

[Lovie777]

3. Oh my .....

although I welcome rain/snow it still sounds dangerous.

[hatrack]

5. Last serious megastorm was 1986 (I think . . . )

On edit - this is when the Auburn cofferdam collapse took place:

From Feb. 11 to Feb. 20, 1986, a series of three storms, each stronger than the previous, brought record-setting rain that, in some areas, overwhelmed flood control measures. In the end, the storms claimed 13 lives, and the damage was estimated at $400 million. The storm also brought eventual changes to California's existing flood control system.

'Atmospheric River' slams Northern California

The February storms were a classic Pineapple Express system, or what we now call an "Atmospheric River." The system was typical of the scenario that has usually given California historic rains. Satellite images from this time show a long line of clouds streaming from south of Hawaii to California. There was a long line of deep moisture being pushed along by a jet stream -- that one pilot report measured in the 200 mph range (that’s very strong).

EDIT

Round 1: The rain begins

Rain started to fall on Feb. 11 in Northern California. The first wave of rain wasn’t too bad, while the rain totals were high, there weren’t any problems caused by the first storm. During the next day and a half, Sacramento received 1.96 inches of rain and Blue Canyon got 4 inches. Those totals are similar to the storm we had this January, and our flood control systems can easily handle rain totals like that.

Round 2: Second storm starts Valentine's Day

The rain didn’t let up for long, but there was a pause between Round 1 and Round 2. The second storm started on Valentine's Day, Feb. 14, 1986, and lasted through Feb. 16. This storm was stronger and wetter than the first. The rain total in Sacramento reached 3.11 inches and Blue Canyon got 11.54 inches. After five days of rain, streams and creeks were near full -- if not overflowing -- and major rivers were running fast. Inflows to Folsom Lake jumped from around 20,000 cubic feet per second (cfs) at the start of Round 2 to around 80,000 cfs at the storm's conclusion.

Round 3: Final storm makes big impact

The final storm began Feb. 17 and lasted through Feb. 20. The rain totals exceeded the two previous storms. Sacramento got 5.13 inches (including 3.21 inches on Feb. 18, setting a record), and Blue Canyon had 18.49 inches. The 18.49 inches of rain Blue Canyon saw in just one storm is nearly the season average for Sacramento. Inflows to Folsom Lake were estimated at 250,000 cfs -- dam operators could only release 130,000 cfs.

EDIT

https://www.kcra.com/article/1986-flood-revisiting-one-of-the-costliest-storms-in-norcal-history-35-years-later/35553920#

[RussBLib]

7. This strikes me as fearmongering.

Sorry, but there is quite enough existential angst already happening without some ominous megastorm which may or may not strike in our lifetimes.

A huge-ass hurricane might strike where I live, but I cannot live in fear. We are prepared, but who knows when it might hit?