Multiple waves of precipitation brought periods of heavy rain, mountain snow and gusty winds to interior Northern California over the Christmas holiday and through the end of the month. Storm total snow amounts of 10 to 40 inches were measured in the northern Sierra Nevada and southern Cascades from December 24th through 29th that led to periods of chain restrictions along the mountain passes.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS STO wrote it up.
Multiple waves of precipitation brought periods of heavy rain, mountain snow and gusty winds to interior Northern California over the Christmas holiday and through the end of the month. Storm total snow amounts of 10 to 40 inches were measured in the northern Sierra Nevada and southern Cascades from December 24th through 29th that led to periods of chain restrictions along the mountain passes. Additionally, there were multiple reports of roadway flooding in the Valley, and mud/dirt/rock slides in the foothills that led to brief road closures lasting a few hours.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sacramento, CA wrote its last area forecast discussion before the first event at Dec 23, 2:03 PM PST, 13 hours earlier.
Area Forecast Discussion National Weather Service Sacramento CA 203 PM PST Mon Dec 23 2024 .SYNOPSIS... Periodic chances for moderate precipitation and breezy to gusty southerly winds are expected to continue through the weekend as a series of weather systems impacts the region. Isolated thunderstorms possible on Tuesday. .DISCUSSION... Cloudy skies continue to blanket much of interior Northern California as light showers ahead of the next system start to shimmy over the Coastal Range. This next system, which arrives later tonight and lasts into Tuesday, is expected to be stronger and colder than previous weekend systems. Current probabilities of exceeding 1 inch of liquid precipitation are around 70-100% across the northern Sacramento Valley, foothills and mountains. Forecast precipitation totals sit around 0.25-1" across the Valley, with 1-2.5 inches possible along the Sierra/southern Cascades and foothills. Snow levels will start above pass levels, but rapidly lower to around 5000-6500 feet by Tuesday morning. NBM advertises a 60-90% probability of exceeding 6 inches of snowfall through Tuesday evening. Moderate mountain snow is expected, with snowfall rates up to 1-2.5" per hour possible Tuesday morning. A Winter Weather Advisory remains in effect for the southern Cascades and northern Sierra for elevations above 6000 feet from 7 AM to 7 PM Tuesday. Total snow accumulations of 5 to 10 inches are forecast above 6000 feet; locally higher amounts over peaks. Additionally, NBM depicts a 10-20% probability of thunderstorm development on Tuesday. Isolated thunderstorms will be possible along the main frontal band as it passes through early tomorrow morning, and also behind the front with some possible clearing late morning into the early evening. Gusty southerly winds are also anticipated late Monday night through Tuesday morning as the system moves through, with gusts up to 25-35 mph over the northern Sacramento Valley and northeast foothills; stronger gusts over the Sierra. Precipitation chances are expected to taper off Tuesday night, with overall dry conditions anticipated for much of Wednesday (Christmas Day) as short-lived ridging moves overhead. With a drier period expected to follow, additional chances for fog development will likely be possible (10-20% probability of visibilities less than 1 mile). Ensembles indicate an active pattern continuing through the weekend. The next wave is expected to arrive late Wednesday night or early Thursday, bringing another round of widespread Valley/foothill rain and mountain travel impacts. Snow levels will start around 4500 to 5500 feet early Thursday, then increase to around 5500-6000 feet by Thursday afternoon. Moderate snow is possible, with probabilities of snowfall exceeding 6 inches above 6000 feet ranging from 40% to 70% through Thursday night. Breezy southerly winds will accompany the system. Please continue to check weather.gov/sto for the latest updates and check quickmap.dot.ca.gov before you go this holiday season! .EXTENDED DISCUSSION (Friday THROUGH Monday)... While uncertainty remains, ensembles suggest an active pattern persisting late week into the weekend as additional waves move across the area. Probabilities of liquid precipitation exceeding 0.5 inches range from 40% to 60% across the Delta and southern Sacramento through Sunday night, while probabilities of exceeding 1 inch around 60% to 95% favor the northern Sacramento Valley, foothills and mountains. Probabilities of snowfall exceeding 6 inches above 6000 feet through Friday evening sit around 20% to 50% at this time, with minor to moderate mountain travel impacts. Snow levels start around 6000 feet Friday morning, then rise above pass levels by Saturday. Drier conditions may return by early next week. Please continue to check weather.gov/sto for the latest updates and check quickmap.dot.ca.gov before you go this holiday season! && .AVIATION... MVFR/IFR with localized LIFR conditions from low ceilings and scattered showers north of I-80 this afternoon. Valley and mountains from 00z Tue through 12z Tue as light to moderate precip. develops. Light southerly winds less than 12 kts expected until 00z Tue, then 15-30kt gusts through the Valley with 35-45 kts along the Sierra crest after 09z Tues. Snow levels around 6500-7500 feet, becoming 8000-9000 feet after 00z Tue. Snow levels then drop to 5000-6000 feet after 18Z Tuesday. Isolated thunderstorms will also be possible between 12z Tuesday through 00Z Wednesday for much of the Valley, foothills, and Sierra. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 7 AM to 7 PM PST Tuesday for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. &&
The national radar mosaic for the moment the first event began.
14 flood, 1 debris flow. Local standard time, as filed.
California Highway Patrol reported roadway flooding from heavy rain near Lake California Drive and Del Mar Drive just east of Interstate 5.
California Highway Patrol reported roadway flooding from heavy rain on State Route 36 near Mile Marker 49.4.
California Highway Patrol reported roadway flooding from rain along eastbound Interstate 80 and Cordelia Offramp.
California Highway Patrol reported roadway flooding from heavy rain with 1 foot of water across the roadway at Granada Drive and Bonita Way.
California Highway Patrol a mud/dirt/rock slide on Highway 36 near Mile Marker 60.50, 4 miles west of Payne's Creek. Both lanes were blocked as a result.
California Highway Patrol reported the eastbound side of the roadway flooded on Old River Road near County Road 126.
California Highway Patrol reported roadway flooding on State Route 36 and Antelope Boulevard from heavy rain.
California Highway Patrol reported roadway flooding across both lanes on Highway 99 at Keefer Road from heavy rain.
California Highway Patrol reported roadway flooding on Highway 99 and Blackberry Avenue from heavy rain. Highway 99 was closed between Blackberry Avenue and Electric Avenue for about 1.5 hours.
California Highway Patrol reported a mud/dirt/rock slide on Cohasset Road.
California Highway Patrol reported flooding in the northbound lane of Highway 99 at Long Creek Bridge from heavy rain.
California Highway Patrol reported roadway flooding with water coming into the northbound lane on Highway 99 at Cana Pine Creek Road.
California Highway Patrol reported roadway flooding of Highway 99 at Tecate Road. Vehicles were barely able to pass.
California Highway Patrol reported roadway flooding on southbound Highway 99W at Vina Ave.
Caltrans reported a rockslide 3.5 miles east of Belden along State Route 70. The road was closed for about 4 hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2024Every state in 2024This day in weather historyWarnings in California, December 2024
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1222767, 1222768, 1222769, 1222770, 1222782, 1222771, 1222772, 1222773, 1222774, 1222783, 1222775, 1222776, 1222777, 1222778, 1222779.