February 2024 California atmospheric rivers
{{Short description|Weather event}}
{{Further|2023–24 North American winter}}
{{Use mdy dates|date=June 2024}}
{{Infobox flood
| name = February 2024 California atmospheric rivers
| image = February 4th Atmospheric River.png
| image_size =
| alt =
| caption = GOES-West satellite view of the bomb cyclone impacting California on February 4
| date = February 4–7, 2024
| damages = ~$3 billionhttps://www.gov.ca.gov/wp-content/uploads/2024/03/3.22.24-MDD-request-for-early-Feb.-storms.pdf
| affected = California
| cause = Atmospheric river associated with an Extratropical cyclone
}}
In early February 2024, two atmospheric rivers brought extensive flooding, intense winds, and power outages to portions of California. The storms caused record-breaking rainfall totals to be observed in multiple areas, as well as the declaration of states of emergency in multiple counties in Southern California.{{Cite web |title=Southern California sees record-setting rain totals {{!}} abc7.com |url=https://abc7.com/amp/storm-rain-totals-in-southern-california/14388316/ |access-date=2024-02-06 |website=abc7.com}}{{Cite web |date=2024-02-06 |title=California storm full coverage: State of emergency declared as atmospheric river brings 'potentially historic' flood threat |url=https://news.yahoo.com/california-storm-full-coverage-state-of-emergency-declared-as-atmospheric-river-brings-potentially-historic-flood-threat-151348871.html |access-date=2024-02-06 |website=Yahoo News |language=en-US}} Wind gusts of hurricane force were observed in San Francisco, along with wind gusts reaching over 100 miles per hour (160 km/h) in the Sierra Nevada.{{Cite web |date=2024-02-05 |title=Hurricane-force gusts topped 100 mph in Bay Area during rare storm |url=https://www.kron4.com/news/bay-area/hurricane-force-gusts-top-100-mph-in-bay-area-during-rare-storm/ |access-date=2024-02-06 |website=KRON4 |language=en-US}}{{Cite web |date=2024-02-05 |title=Wind Gusts Topped 100 MPH In Marins Coastal Mountains |url=https://patch.com/california/sanrafael/wind-gusts-topped-100-mph-marins-coastal-mountains |access-date=2024-02-07 |website=San Rafael, CA Patch |language=en}} Widespread landslides occurred as a result of the storms, as well as multiple rivers overflowing due to the excessive rainfall.{{Cite web |title='1-in-1,000 year rain' event: State of emergency due to floods, mudslides in California: Updates |url=https://www.usatoday.com/story/news/nation/2024/02/05/california-weather-floods-mudslides-atmospheric-river-updates/72477613007/ |access-date=2024-02-06 |website=USA TODAY |language=en-US}} Stormchaser Reed Timmer stated that "Biblical flooding" was possible throughout California during the atmospheric river.{{cite web |last1=Timmer |first1=Reed |author1-link=Reed Timmer |title=CAT 5 - California Biblical Flooding possible Today |url=https://www.youtube.com/watch?v=yXf2iCdcYXQ |website=YouTube |publisher=@ReedTimmerWx |access-date=4 February 2024 |archive-url=https://web.archive.org/web/20240204193534/https://www.youtube.com/watch?v=yXf2iCdcYXQ |archive-date=4 February 2024 |location=California |format=YouTube video |date=4 February 2024 |url-status=dead}}
Meteorological history
File:WPC Excessive Rainfall Outlook for California on February 4, 2024.jpg
File:NOAA California Atmospheric River.png
From February 1 to February 2, 2024, California experienced the impact of the first Pineapple Express storm caused by the atmospheric river, which subsequently traversed the United States and settled over the I-25 corridor in Colorado.{{citation needed|date=February 2024}}
Another storm struck on February 4, with the National Weather Service categorizing it as "potentially life-threatening", and forcing Los Angeles into a state of emergency.{{Cite web |last=Oberholtz |first=Chris |date=2024-02-02 |title=Los Angeles, San Diego under State of Emergency as atmospheric river lashes Southern California |url=https://www.foxweather.com/weather-news/flood-rain-snow-wind-california-atmospheric-river-weekend |access-date=2024-02-05 |website=FOX Weather |language=en-US}} Seven additional counties declared a state of emergency: Orange County, San Bernardino County, Riverside County, San Diego County, San Luis Obispo County, Santa Barbara County, and Ventura County.{{Cite web |last=CityWatch |date=2024-02-04 |title=Pineapple Express Storm Hits Los Angeles: State of Emergency Declared |url=https://www.citywatchla.com/los-angeles/28382-pineapple-express-storm-hits-los-angeles-state-of-emergency-declared |access-date=2024-02-05 |website=www.citywatchla.com }}{{Cite web |date=2024-02-04 |title=Emergency declaration and urgent warnings as Southern California storm gains ferocity |url=https://www.latimes.com/california/story/2024-02-04/powerful-winter-storm-moves-into-southern-california |access-date=2024-02-05 |website=Los Angeles Times |language=en-US}} The rain was expected to last for days, with some parts of California expected to receive record amounts of rain.{{Cite news |title=Atmospheric River Could Bring 'Life-Threatening Flooding' to Southern California |work=The New York Times |date=2 February 2024 |url=https://www.nytimes.com/2024/02/02/us/california-atmospheric-river-storm-forecast.html |last1=Jones |first1=Judson }}
Various news outlets projected that Los Angeles might witness an accumulation of rainfall equivalent to six months' worth between February 3 and February 5. Simultaneously, the Sierra Nevada mountains were anticipated to receive 1 to 3 feet (30 to 91 cm) of snow, while higher elevations, such as Mammoth Lakes, CA, could potentially experience over 4 feet (120 cm) of snow. The NASCAR exhibition race at the Los Angeles Memorial Coliseum was moved forward one day to February 3 from the scheduled February 4 race in anticipation of the rainstorm. Additionally, portions of the San Bernardino Mountains' foothills were expected to receive substantial rainfall, with estimates ranging from 10 to 12 inches (250 to 300 mm). One man was killed on February 4 after a tree struck him due to the winds.{{Cite news |date=2024-02-05 |title='Catastrophic' flooding to hit California as bad weather continues |url=https://www.bbc.com/news/world-us-canada-68202944 |access-date=2024-02-05 |language=en-GB}}
= February 5 =
Downtown Los Angeles received {{convert|4.1|in|mm}} of rain on February 4, 2024, marking it the wettest day since March 15, 2003. Several Malibu, California schools were closed due to inaccessibility because of severe weather causing road closures.{{Cite web |author=Mary Gilbert, Antoinette Radford and Eric Zerkel |date=2024-02-05 |title=Malibu schools are closed due to weather-related road closures |url=https://www.cnn.com/us/live-news/california-atmospheric-river-flooding-rain-02-05-24/h_41c653a5934d11477c7ae8959b9eb367 |access-date=2024-02-05 |website=CNN |language=en}} Power outages caused by the storms left approximately 850,000 people without power.{{Cite news |title=California Power Outages Affect More Than 850,000 Customers |work=The New York Times |date=5 February 2024 |url=https://www.nytimes.com/2024/02/04/us/california-power-outages-storm-wind.html |access-date=February 5, 2024 |last1=Albeck-Ripka |first1=Livia |last2=Knight |first2=Heather }}{{Cite web |date=2024-02-05 |title=Over 500,000 without power in California |url=https://www.nbcnews.com/news/weather/live-blog/potentially-life-threatening-storm-system-begins-pounding-california-l-rcna137204 |access-date=2024-02-05 |website=NBC News |language=en}} Fallen trees blocked roads and cut power lines in multiple locations. Wind gusts up to 162 mph (260 km/h) occurred at various high elevation locations, including the Sierra Nevada mountains and Lagunitas Forest.{{Cite web |author=Mary Gilbert, Antoinette Radford and Eric Zerkel |date=2024-02-05 |title=Ferocious wind gusts hit 162 mph in the Sierra Nevada mountains |url=https://www.cnn.com/us/live-news/california-atmospheric-river-flooding-rain-02-05-24/h_f1ad3351cf6b8e5b4fb9f1d5837c6782 |access-date=2024-02-05 |website=CNN |language=en}}{{Cite web |last=Speck |first=Emilee |date=2024-02-05 |title=Atmospheric river drenches Los Angeles with record-setting rain, blasts Sierra with 160-mph winds |url=https://www.foxweather.com/extreme-weather/atmospheric-river-california-rain-totals-wind-snow-stats |access-date=2024-02-06 |website=FOX Weather }} As of February 5, at least three people had died from falling trees.{{Cite web |date=2024-02-05 |title=Death toll at 3 as California storm brings heavy rain, flooding, mudslides |url=https://www.latimes.com/california/story/2024-02-05/stunning-rain-mudslides-flooding-thrash-southern-california-dangerous-storm-isnt-done |access-date=2024-02-06 |website=Los Angeles Times |language=en-US}}
= February 6 =
Downtown Los Angeles had received {{convert|7.03|in|mm}} of rain in two days from February 4–5 making it the third wettest two-day span in the city's history. For reference, Downtown Los Angeles only averages {{convert|14.25|in|mm}} of rain in a normal rain year.{{cite web |title=Summary: Major CA Winter Storm (4-6 Feb 2024) |website=Center for Western Weather and Water Extremes |publisher=University of California-San Diego |date=February 14, 2024 |url=https://cw3e.ucsd.edu/summary-major-ca-winter-storm-4-6-feb-2024/ |access-date=January 23, 2025}} Heavy rainfall caused more than 300 landslides and severe flash flooding throughout the state.{{Cite news |last1=Cappucci |first1=Matthew |last2=Livingston |first2=Ian |date=February 6, 2024 |title=After record rains, California storm shifts east. What's next? |url=https://www.washingtonpost.com/weather/2024/02/06/california-atmospheric-river-forecast-rainfall-totals/ |access-date=February 6, 2024 |newspaper=The Washington Post}} San Diego received record rainfall for California at higher elevations causing floods and prompting road closures.{{Cite web |last=Staff • • |first=NBC 7 |date=2024-02-06 |title=Heavy rain floods roads, prompts road closures for San Diego County |url=https://www.nbcsandiego.com/news/local/closed-or-flooded-roads-in-san-diego-county/3426003/ |access-date=2024-02-06 |website=NBC 7 San Diego |language=en-US}} Two tornado warnings would be issued for portions of San Diego County by the National Weather Service due to a severe thunderstorm produced by the storm complex, although no damage would be caused.{{cite web |date=2024-02-06 |title=National Weather Service lifts tornado warning for San Diego County; no damage reported |url=https://www.sandiegouniontribune.com/news/public-safety/story/2024-02-06/tornado-warning-issued-for-parts-of-south-county-east-county |access-date=2024-02-06 |website=San Diego Union-Tribune }}{{Cite web |date=2024-02-06 |title=Tornado Warning Issued For Parts Of San Diego County |url=https://patch.com/california/santee/tornado-warning-issued-parts-east-county-south-bay |access-date=2024-02-06 |website=Santee, CA Patch |language=en}}
= February 7 =
File:2024 Southern California floods.jpg
Downtown Los Angeles had received {{convert|8.51|in|mm}} of rain from February 4–6 making it the second wettest three-day span. Following {{convert|1.66|in|mm|abbr=on}} of rain in Death Valley in 72 hours, California State Route 190 was closed and the park experienced a setback in the recovery from Hurricane Hilary.[https://www.nbcnews.com/news/weather/california-rainstorms-brought-kept-lake-death-valley-rcna138211 California rainstorms brought — and kept — a lake at Death Valley], NBC News, February 7, 2024[https://www.reviewjournal.com/local/local-nevada/death-valleys-recovery-from-hilary-delayed-by-new-rain-2996535/ Death Valley’s recovery from Hilary delayed by new rain], Las Vegas Review Journal, February 8, 2024 Two tornadoes were confirmed to touch down in San Luis Obispo county.{{cite web |last1=Schlepp |first1=Travis |title=NWS confirms 2 tornadoes touched down on California Central Coast |url=https://ktla.com/news/california/nws-confirms-2-tornadoes-touched-down-on-california-central-coast/#:~:text=The%20National%20Weather%20Service%20has,Pismo%20Beach%20and%20Grover%20Beach. |website=KTLA.com |access-date=26 February 2024}}
Impact
Significant amounts of snow fell in the Sierra (2–4 feet) which brought the snowpack from 50 to 70% of average to 70-80% of average. Landslides and fallen trees due to the heavy rain and high wind gusts destroyed and damaged many homes and closed roads throughout California. Bel-Air had a peak 24-hour rainfall of {{convert|12.42|in|mm}} which equates to a 380-year return interval (0.3%).Los Angeles had been incorporating elements of a stormwater harvesting design to retain the rainwater. From February 4 to 7, the city captured 8.6 billion gallons of water, equivalent to the yearly needs of 106,000 homes.{{cite news |last1=Simon |first1=Matt |title=Los Angeles Just Proved How Spongy a City Can Be |url=https://www.wired.com/story/los-angeles-just-proved-how-spongy-a-city-can-be/ |access-date=28 February 2024 |work=WIRED |date=19 February 2024}} Most of Southern California was 150%-300% of average from October 1 to February 7. Most places throughout Northern California were still 50%-110% of average after the storms.