A major winter storm, with winds gusting up to near hurricane strength is moving towards northern California. Dubbed a “bomb cyclone” due to rapid central pressure drop, it more than qualifies for the 24 millibars (mb) in 24 hours “bomb” cyclone designation.
As of 11AM Wednesday Jan 4th, the central pressure of the storm as it was just off the California coast was 28.33 inches (959.36 millibars) as seen in the graphic below. That pressure is lower than the centrral pressure of many hurricanes.

The National Weather Service (NWS) has produced forecasts for areas of likely flooding that covers much of the Sacramento Valley and the north coast.
Because this winter storm is relatively warm, snow levels are averaging higher, causing rain to fall on snow-laden areas, creating snow-melt which will overwhelm already waterlogged soil, making for fast runoff into creeks and rivers.



The NWS has issued a Winter Storm Warning for the Northern Sierra Nevada.
Heavy snow expected. Total snow accumulations of 4 to 10 inches, except 6 to 18 inches west of Highway 395. Lowest valleys below 4000-4500 feet elevation are only expected to see up to 3 inches of snow.
…
Snow levels will start off below 4000 feet before briefly increasing to 5000-6000 feet Wednesday afternoon. Snow levels will then fall again to 4500-5000 feet Thursday. This storm will come in 2 parts, and areas east of Highway 395 may see a brief break Wednesday evening.
For the areas Near lake Tahoe, the NWS advises the situation is even worse:
Heavy snow expected. Total snow accumulations of 8 to 14 inches, except 1 to 2 feet above 7000 feet. Localized amounts up to 3 feet are expected for the Sierra crest. Winds gusting as high as 100 mph over Sierra ridgelines with gusts up to 40 mph in the Tahoe Basin.
In addition, widespread damaging winds are forecast from this winter storm.



Winds on the valley floor are expected to gust as high as 60 mph, with higher elevations seeing stronger wind gusts.
Dr. Ryan Maue had this to say on Twitter:
Watching CNN this morning talking about the storm, I was appalled and how smoothly they have transitioned from Severe Drought to Floods! The CAGW Loonies need to transition to humans.
Well said.
Our permanent warming and drought in Colorado is among the coldest and wettest.
Then why is Lake Mead empty? Should we be blaming greedy Coloradans? 😉
Well that’s why it’s called a Climate Crisis silly. It’s all about the CAGW Loonies bomb. I’m working feverishly on a grant for controlled humidicrib environment with no touchscreens as treatment. The computer modelling should clinch it.
If the real problem is that the right amount of rain is falling but in the wrong places, then we should consider building a national (or even world) water-pipeline grid to move it around, as we do with electricity. As far as I can tell, all the reasons we don’t are political, not technical.
So … will this result in permanent drought or permanent flooding?
Both have been claimed as the result of using fossil fuel.
Or maybe the claim itself is the permanent “bomb”?
Have “winter bomb cyclones” happened on the West Coast before?
When? (Assuming they didn’t come with a new name for past events.)
What caused them?
After ‘bomb cyclone’ soaks West Coast, Yosemite Falls roars back to life”This is such a joy to see,” one observer said.
https://www.nbcnews.com/news/us-news/after-bomb-cyclone-soaks-west-coast-yosemite-falls-roars-back-n1282345
Oct. 25, 2021, 11:28 PM CDT
By Tim Stelloh
A powerful storm that drenched the West Coast with record-breaking rainfall and hurricane-force winds triggered landslides, flooded roads and left two people dead in Washington State.
It also resurrected one of California’s most iconic natural features — Yosemite Falls.
Before a “bomb cyclone” slammed into the state Sunday, dropping nearly a foot of rain in some parts of a region strained by a climate change-fueled megadrought, the 2,425-foot falls had all but vanished, as often happens by late summer or fall.
But by Monday, more than six inches of rain had fallen across Yosemite Valley in 36 hours, the park said on Facebook. And the falls roared back to life, as one observer put it on Twitter.
https://twitter.com/i/status/1452449401633267713
So beautiful, Yosemite Falls.
“Bomb cyclone” is a bogus neologism. See my other remarks above.
It’s been par for the course for many years now.
Every weather event has to have some extra superlative attached to it.
Thus, hurricanes or storms always “slam into” something. And it’s no accident that you are often told this by a very attractive female “weather girl”.
One of my favorites is when they say a storm is “targeting” something.
It’s all in the presentation.
https://youtu.be/tocuyJ1Fu7U
Permanent drought-flood – part of the weather weirding thing.
What’s “weird” is that some believe these contradictory claims are, somehow, “proof” that fossil fuels are the “cause” of all of it.
Right up there with that end of snow-heavier snow thing.
Relax…over the past 100 years ALl climate related deaths (including floods) have decreased by nearly 99%. Let’s tell that story as often as possible. Totally disarms any predicated catastrophes.
Thanks, Anthony.
Regards,
Bob
Sorry, Anthony. This is not to downplay your post in any way, but, with the term bomb cyclone, I had to:
Francois: Do you know what kind of bomb it was?
Clouseau: The exploding kind.
Regards,
Bob
So … they’re dropping a bomb claim that will explode itself?
Sounds about right.
But isn’t it a berm?
“Beum”. Because it goes “beum.”
If it was “berm”, that would be a “berm cyclone”, and that would make no sense.
I blame the merth and the minkey, or though that could be A Shot in the Dark.
But it’s a very dry bomb cyclone don’t ya know and all caused by “he who must be named, CO2”
Bomb is scary ….but CAGW Cyclone is coming next.
And as the Democratic Peoples Republic of California has done nothing to add water storage, this will do little about the drought.
They do continuously drain some reservoirs in order to protect minnows/smelt fisheries.
I wish they could develop a viable mutually beneficial aquaculture.
My understanding is that the problem with the Delta Smelt is introduced Striped Bass predation, not water per se.
The true problem with the delta smelt is that none have been observed for years. But CA keep pretending it still exists virtue signaling by wasting water and crippling agriculture.
Creating Energy and Food shortages is central to their “plans.”
Once they have entrenched those shortages via their advocated “policies,” they will then have the excuse to dictate the “solutions” to the crisis THEY CREATED.
Isn’t that the whole point of governments – to solve the crises and problems they have created?
The published rationale for plans like that is that building enough infrastructure would encourage more people to move here.
If you don’t want that to happen, why not just ban it? Create transferable permits to live in this state. Issue one per legal resident. Then stop issuing them.
Of course now that California’s tax (and other) laws are driving more people to leave the state than come here, I guess the permits are no longer necessary. What a waste of the nice climate, though.
The (non) problem was that the delta smelt was helped out of existence by Fish and Wildlife by introducing a similar smelt to try to help. First the Delta disappeared then the replacement slowly went away.
No environmental problems associated with having no smelt (of any kind)….
In 24 hours, an Arctic cyclone (stratospheric intrusion) will reach the California coast. A lot of snow will fall in the mountains. We warn that roads will be impassable during the snowstorm. As much rain may fall in the lowlands as in hurricanes.


Another cyclone from the north with precipitation may approach California in the next few days.
Donner, party of 87.
Donner, party of 87… er, make that 86.
There’s always room for one more at our table.
I thought the joke was (when dining at a restaurant in particular), “Donner, party of one?”
You have to get the hostess to go along
“Donner, party of 12”
“Donner, party of 10”
“Donner, party of 5”
When I was constantly hauling loads back and forth across the country I would do my very best to use either I-10 or I-40 during the winter months. But if I had to use a northern Interstate when going to or coming from the left coast during the winter it would be I-80 rather than I-70 or I-90.
I-80 goes through a pass very near that the Donner party tried to use and in fact when using the pass truckers often refer to it as going through “the Donner”.
“Bomb cyclone” is a faddish phrase that’s worse than useless because it’s misleading. A “bomb” is a manufactured device that explodes. A “cyclone” is a natural, low pressure system where wind rushes towards the center. Calling an implosion an explosion doesn’t work, even as metaphor.
The scary term, “bomb cyclone” is another example of weather media striving to be lurid and frightening, rather than precise, which is what meteorology — and science in general — used to strive for. Neologisms for ancient, normal phenomena push understanding in the wrong direction.
More intellectual degradation in service of grabbing eyeballs does NOT serve the public well.
When weather reporting returns to terms like “storm,” and “intense low” we’ll understand more, which ought to be the purpose of science in the first place.
I guess “Atmospheric River” wasn’t scaring the children enough.
Commotio cordis cyclone doesn’t roll off the tongue either.
“Atmospheric River” scared me plenty tonight on the News Hour. Especially when they said that it was caused by climate change.
“Pineapple Express” sounds too cheerful and fun!
“Mostly Peaceful” ?
Okay, time to do some digging. I always thought that the term arose after the New England Blizzard of 1978, the reference standard for a blizzard by nearly all who lived through it.
I found many references to “a [the] 1980 article in the journal Monthly Weather Review.” I finally found it in the October issue at https://journals.ametsoc.org/view/journals/mwre/108/10/1520-0493_1980_108_1589_sdcot_2_0_co_2.xml?tab_body=pdf
So, blame it on Fred Sanders. Apparently there are other references to storms bombing out in the 1940s.
And yes, the term is being used to describe any storm that undergoes bombogenesis – commonly 24 mb pressure fall in 24 hours, though I noted an equation involving the latitude, IIRC, sin(latitude)/sin(60) mb per hour to accommodate the faster development at higher latitudes.
As for lurid and frightening, note that cold and warm fronts refer to wartime battle fronts, only between air masses, not humans.
Even blizzard. From https://www.southcoasttoday.com/story/news/2022/01/28/winter-weather-definition-blizzard-bomb-cyclone-bombogensis-thundersnow-nor-easter-windchill/9242383002/
Perhaps a meteorologist could show a record of how many of these storms with precipitous pressure drops have actually hit the central California coast. Specifically fronts which cause drops equal to or in excess of “24 millibars (mb) in 24 hours”.
My own memory is short but I would guess Colorado has suffered similar crazy barometric drops somwhere across the state just about every year. We had one excitingly dubbed a “bomb cyclone” just before Christmas, December 22. Fort-five degrees and windy as hell when I went into King Soopers; 28 degrees when I came out – and I wasn’t just squeezing the Charmin.
In any case, all those atmospheric rivers of snow have left the Colorado snowpack in good shape for another year. Six of the eight major drainages are way above the average for this time of year and the Western Slope looks particularly good. Colorado Headwaters are at 130% of average; Yampa and the White at 150%.
Best regards for the year of the rabbit.
So now instead of “the blizzard of 78” that event should be named “the bomb cyclone of 78”?
See the problem there?
I suppose the “bomb cyclone” (or “the cyclone bombed out and”) brought _both_ Blizzards in 1978 works for me.
The only names I’m familiar with for rain storms that bomb out and stay rain or mostly rain are “nor’easter” along the Atlantic coast and the “Witch of November” in the upper Mississippi River and Great Lakes.
However, I do agree “bomb cyclone” is way overused.
Well, at my Central Indiana home this last polar blast certainly failed to produce a blizzard. We got the cold,wind, and rain, but barely 3” of snow.
Totally agree. When I was younger (back when I was a kid they still had the tv meteorologist moving warm and cold fronts and highs and lows around on an actual board rather than a computer graphic) things were simple and direct. Storms were just storms….rain was just rain – maybe heavy rain, but rain. A snow storm was just that – a snow storm! Hot weather was hot weather, and not often called a heat wave unless it lasted many days…
“Bomb cyclone” was the term used also in Ontario just before and during Christmas. Plans were cancelled. Roads weren’t maintained. In the end, the snowfall forecasts were drastically downgraded. No one seemed to know why.
Scientist: There is going to be a big winter storm with high winds and precipitation as the system is undergoing explosive cyclogenesis
Reporter: Esplosive cyclo-what the heck is that?
Scientist: it is a rapid intensification of the storm system indicated by a large drop in barometric pressure in the center
Reporter: I’ll lose my readers with all that jargon. Can’t we just call it a “bomb cyclone”?
Scientist: Whatever floats your boat…
This is the current situation. More heavy rainfall is already reaching the northern California coast.


The mountains will hold back the precipitation.
In other words, weather
Yes, we used to call these “cold fronts”
It’s always a ‘bomb’ of some sort nowadays.
Pretty soon that word will lose meaning too
As when the drought scare bombs.
It must be due to the terrible climate change.
https://breadonthewater.co.za/2022/12/15/an-evaluation-of-the-greenhouse-effect-by-carbon-dioxide/
Is there any relationship between this phenomenon in the USA and the unseasonal warm weather on similar latitudes in Europe, and here in the U.K.?
Stratospheric ozone blocks the polar vortex over the Bering Sea. Therefore, the US is exposed to frequent winter stratospheric intrusions (Arctic fronts).


The main front will reach northern California tonight.


“Bomb cyclone” is a highly prejudicial term designed to elicit fear and play into the “warming climate causes extreme weather” bullshit. Entirely made up. It’s just a storm, period.
It’s just a low pressure system, and not at all unusual in the size of storm and wind velocity, or in the volume of snow and rain it is bringing to an area that the warmunists have been wailing about drought over for the last several years.
This is nothing compared to the Great Storm of 1862:
https://en.wikipedia.org/wiki/Great_Flood_of_1862
If the current storm isn’t just “big weather”, then how do you reconcile this with 1862 & AGW ?
Answer : you can’t
From another wiki article: https://en.wikipedia.org/wiki/California_flood_of_1605
“The California flood of 1605 was a massive flood that submerged large portions of present-day California (once known as Alta California). The megaflood was a result of sustained major rain storms across the region, enhanced by an unusually powerful atmospheric river. The flooding affected the indigenous peoples of California, in pre-industrial advancement populations.
In addition to this event, geologic evidence indicates that other “megafloods” occurred in the California region in the following years A.D.: 212, 440, 603, 1029, c. 1300, 1418, 1750, 1810, and 1861–62. United States Geological Survey sediment research revealed that the 1605 flood deposited a layer of silt two inches thick at the Santa Barbara basin, indicating that it was the worst flood event of the past 2,000 years, being at least 50% more powerful than any of the others recorded based on geological evidence.”
I thought wikipedia was biased towards the CAGW view point. Perhaps they are not as biased as some people think.
The “editors” probably just haven’t come across it yet…
“Someone sent us up the bomb!!”
We have a Category 4 Pineapple Express coming to California, according to the Media.
California was whining about the drought they are having, and I guess now, after the Pineapple Express does its thing, they will be complaining about all the water they are getting. You just can’t satisfy some people. It’s always something.
That’s partly from the miscommunication continually received by most people about the weather.
What is drummed into people’s heads is the incorrectly stated notion that a 30-year average is “NORMAL,” when it is nothing of the kind; it is just a long-term average, which at the end of the day would more correctly be described as a “midpoint of extremes.”
Take the recent drought and the coming Pineapple Express and divide by two, and you’ll probably be pretty close to what is incorrectly referred to as “normal.”
not a meteorologist like my dad. But rapidly intensifying lows (bomb cyclones) are not unusual, just mostly intensification unpredictable.
Yeah, but, “bomb” sounds so scary! That’s why alarmists use the term.
I suggest we use Thermobaric Cyclone. It’s a great word. It has reference to heat as well as the barometer.
Is the atmospheric river the reason for the really warm anomaly in the NH today?
The atmospheric river and the warmth are connected.
The atmospheric river is being driven by the subtropical jet stream and that same jet stream is bringing in mild Pacific ocean air to the south and the east in the United States.
Here’s a picture of it:
https://earth.nullschool.net/#current/wind/isobaric/500hPa/orthographic=-100.01,25.94,264
It hasn’t flooded this bad since the last time it flooded this bad.
A stationary low in the upper troposphere will direct more fronts with precipitation to California. It has currently generated a secondary low in southern California.


The heaviest rainfall is now occurring in the California Valley near Sacramento, where the threat of flooding is increasing.
Never let a weather event go to waste that’s what the Guardian tells us.
I can not think of a singe weather state that isn’t attributed to human induced Climate Change.
Does anyone know what normal weather looks like anymore?
For normal weather just look out of the nearest window.
There’s weather that isn’t attributed to ‘climate change;” it’s called any weather that’s not “bad.”
I don’t know about other areas, but the effects of this “bomb cyclone” on the Bay side of SF is meh. A little higher wind than normal, but nothing severe. The hummingbird on my balcony was sitting on his favorite perch during rainy days as normal.
Rain was less than last week (pre “bomb cyclone”).
Nothingburger so far (4 am Thursday)
Arctic cyclone hits west coast of US. Large amounts of snow will fall in the mountains and rain in the lowlands in California. More fronts with precipitation will come in from the north.


So….”climate change” caused the drought, and then “climate change” fixes the drought. Hmmm. Seems to me like “climate change” routinely cancels itself out.
California’s natural climate is drought and flood, flood and drought. I grew up in Los Angeles, and lived in South California until I was 22 years old. I fought brush fires, I fought flooding and mudslides and raging creeks that were washing coastal cities into the sea.
During the same period, we suffered (lack of) water emergencies on a regular basis.
That is the climate there — these storms are not the exception but the rule.
Many will comment on the historic storm that left nearly the entire Central Valley of California a lake in the 1800s. All the wonderful rich soil is there in the Central Valley because of these types of events washing the hills and mountains into the valley.
Note that this series of storms is bring much needed water and snow pack to the help modify the long-term drought across the entire Southwest.
—the name of the type of storm is being used by doom-sayers to their advantage “BOMB cyclone” — its a bomb, run for your life!
Another cyclone from the north is approaching the US west coast.


Interesting that heavy CA rain is usually associated w/El Ninos, but here it happens during La Nina w/storms moving southeastward.
You Dropped The Bomb On Me
The stratospheric polar vortex is blocked over the Bering Sea by the accumulation of ozone in the region.


https://earth.nullschool.net/#2023/01/06/1300Z/wind/isobaric/10hPa/orthographic=-137.76,69.88,406
Precipitation accumulates on the western side of the mountains.


Meanwhile, frigid air from over central Canada will flow toward the Great Lakes.


Another low from the north is fast approaching California. The front will again pull a lot of moisture from the south.


At least two more cyclones from the north will reach California in the next few days.


Warning for California of impending heavy precipitation.
A secondary low with heavy precipitation reaches California. It will stop over the mountains.


One more low is waiting in the Pacific lined up for California. It too will bring heavy precipitation.


In two days another cold front will reach California, in four days another.
Does the storm get a name? If not, why not?
Very heavy precipitation north of Sacramento. Heavy snowfall in the mountains.


The low is located over California.