A series of atmospheric rivers has been aimed at California this week, bringing torrents of rain and high winds since 2023 began. Atmospheric rivers are flowing columns of water vapor that can dump high amounts of precipitation in a relatively short time. Plus, the storm that’s striking California this week (January 4-6, 2023) underwent what meteorologists call bombogenesis. That’s when a mid-latitude storm’s low pressure falls by 24 millibars within 24 hours. When that happens, the storm rapidly intensifies.
Our #GOESWest?? full-disc satellite shows a powerful storm undergoing bombogenesis off the northern CA Coast.
What is a “Bomb Cyclone”? By definition, it is a low pressure system that experiences a fall in pressure of 24 millibars in 24 hours. #CAwx https://t.co/zmYAPqXknp pic.twitter.com/IDnazirGPx
— NWS Sacramento (@NWSSacramento) January 4, 2023
California experienced an earlier onslaught of precipitation on New Year’s Eve from an atmospheric river. And even when this current storm passes, the extended forecast for California still shows increased precipitation, as the atmospheric river will continue to aim for the West Coast. As a matter of fact, the National Weather Service’s outlook for January 10-14 still has California at 80-90% above normal for precipitation.
Here are the latest Key Messages highlighting the series of atmospheric rivers that will continue to significantly impact CA into next week. Considerable flood impacts and dangerous mountain travel will resume over northern and central CA Saturday, and carry into Tues. pic.twitter.com/zC62ajyoR7
— NWS Weather Prediction Center (@NWSWPC) January 5, 2023
#AtmosphericRiver storm train continuing to roll into the West Coast through next week pic.twitter.com/wNbgbgOzzn
— Jay Cordeira (@jaycordeira) January 5, 2023
Here are the precipitation totals so far for the series of atmospheric rivers affecting California that began on December 26, 2022. We will add to these totals in the next couple weeks as additional systems are expected. For more data, visit https://t.co/6wTyTSKPbx pic.twitter.com/yNSGtQuFE4
— NWS Weather Prediction Center (@NWSWPC) January 5, 2023
Bomb cyclone has impressive strength
Because the storm system is so strong, the Air Force sent five Hurricane Hunter planes to California to monitor and track it. Marin County, north of San Francisco, had one recorded wind gust of 101 miles per hour (about 160 kph)!
With the band of showers moving out of the area, we’ve gotten a little bit of time to look back at last night’s peak wind gusts.
The “winner” is Pablo Point in the Marin County mountains, recording a gust of 101 mph! #CAwx pic.twitter.com/yhvoKxhaHF
— NWS Bay Area ? (@NWSBayArea) January 5, 2023
Impressive wind showing up in Marin. Gusts up to 85 mph now (4:10-4:30)! #cawx pic.twitter.com/D2VSUN768s
— NWS Bay Area ? (@NWSBayArea) January 5, 2023
Impacts from the massive storm
As of Thursday morning, January 5, the storm had claimed two lives in California. A redwood tree falling onto a home killed a two-year-old, and a 19-year-old woman hydroplaned on a partly flooded road, striking a utility pole.
Also, there were many reports of flooding on roads on social media, and high winds closed some ski resorts in the Sierra Nevadas.
Lots of flooding for days now. And it’s not easy to see while driving. Be careful out there #LosAngeles #BombCyclone #PineappleExpress #LARain pic.twitter.com/UykXCuTWjz
— Chhaya Néné (@ChhayaNene) January 5, 2023
#flooding on #highway101 this morning ? #bayarea #sanfrancisco #rain #weather #atmosphericriver #morningcommute pic.twitter.com/FN8NHC75bW
— Liz Dzeng, MD, PhD, MPH (@LizDzeng) December 31, 2022
? Aptos – we’re experiencing coastal flooding along the coastal roads. Please avoid the area. pic.twitter.com/uVANMQY52M
— CHP Santa Cruz (@CHPscrz) January 5, 2023
BREAKING: Capitola Wharf was split in half when a section of the wharf collapsed into the ocean. 30-foot waves, powerful tidal surges, and gusty winds are battering the beaches right now. Capitola Village is flooded.
(Video by Autumn Rose Purdy) #AtmosphericRiver pic.twitter.com/vTfqA8FEa9— Amy Larson (@AmyLarson25) January 5, 2023
TRAFFIC ALERT: UPDATE @Pacifica Continue to avoid N/B SR-1 past Manor Dr. Landslide blocking #2 lane. @CHPSanFrancisco onscene. An update will be posted. https://t.co/xcJOOkL6Kk pic.twitter.com/tfAWPS3Be4
— Pacifica Police (@PacificaPolice) January 5, 2023
A little bit windy at Palisades Tahoe ski resort on Wednesday. (Credit: Marucs Morgan – Palisades Tahoe) pic.twitter.com/Rlco7YLgBA
— KSBW Action News 8 (@ksbw) January 5, 2023
Alleviating drought?
So will all this rain and snow help alleviate the drought in California? On January 3, Scooty Nickerson of the Bay Area’s Mercury News said:
California’s Sierra is closing in on the 2nd-largest snowpack we’ve seen at this time of year in the last two decades.
But, he said, it’s too early to declare an end to the drought, because:
Last year, we started 2022 with a similar bounty – and then ended the snow season way, way, way below normal.
While some of the reservoirs are starting to feel the impact of the atmospheric river, it’s not affecting all of them. For example, Lake Mead gets its water from the Colorado River, which is to the east. By the way, you can track the water levels in California’s reservoirs at its Department of Water Resources website.
Week over week drought classification/improvement. Area in D4 (Exceptional Drought) is no longer on the map. The drought monitor class change map also helps show where there was 1 class (category) improvement. #CAwx pic.twitter.com/NlltVDBlwc
— NWS Bay Area ? (@NWSBayArea) January 6, 2023
22,400,000,000,000 gallons of water is a fairly conservative approximation of what will fall over the state of California over the next 15 days. That’s 22 Trillion , 400 billion gallons! #cawx Too bad it cant all be caught and stored. pic.twitter.com/ZxeqvxBgS1
— Michael Snyder (@SeattleWXGuy) January 4, 2023
The wettest 10 day period for Downtown San Francisco since 1871! Downtown San Francisco received 10.33″ Dec 26 – Jan 4 (yesterday). All time 10 day record was 14.37″ in Jan 1862. #cawx
— NWS Bay Area ? (@NWSBayArea) January 5, 2023
?? Check out this awesome picture of the Phantom Falls in the North Table Mountain Ecological Reserve north of Oroville, CA! All the rain over the last week has led to these normally dry creeks becoming waterfalls. #CAwx
Photo Credit: Mike Manzone pic.twitter.com/xsB2n1oRCG
— NWS Sacramento (@NWSSacramento) January 6, 2023
Bomb cyclone was not a surprise
At least, there was plenty of warning that the storm was coming. Weather forecasts showed satellite images of the giant swirl in the atmosphere days in advance as it approached the coast. And shoppers in California stocked up at the grocery stores in advance of the storm, emptying shelves.
The changing of the guard: watch as #GOES18 takes over for #GOES17 in this #GOESWest water vapor loop. Big storm for the first day on the job! And a seamless transition. Great job @NOAASatellites. pic.twitter.com/zyNkRM5335
— UW-Madison CIMSS (@UWCIMSS) January 4, 2023
The produce department at the grocery store right now. Guess people took the storm warnings seriously pic.twitter.com/YajpwcF3YV
— Zephyr (@CeciliaQuick) January 4, 2023
Bottom line: A bomb cyclone hit California this week, bringing high winds plus heavy rains and snow. More rain is on the way.
