Three dead as California hit by a series of storms over Christmas period.

Three people have died and many others have been affected by flooding as California has been hit by a series of storms over the Christmas period. A 74-year-old man from Redding, in Shasta County, died on the weekend of 20-21 December 2025, after his car became trapped in floodwaters, despite efforts by local police officers to rescue him. On Monday 22 December a woman in her 70s died after being swept into the sea by a large wave at MacKerricher State Park in Mendocino County. On Wednesday 24 December a 64-year-old man from San Diego was struck by a falling tree.

A car partially buried by a mudslide in San Bernadino County, California. CBS News.

Many areas have been affected by flooding, with some communities in San Bernadino County facing evacuation orders in order to keep them safe. Several flash floods have been reported in Los Angeles County, where 27 cm of rainfall was recorded on Wednesday 24 December, with a large landslip reported in Altadena, on a slope which had been stripped of vegetation by wildfires in January this year. Around 130 households were evacuated due to concerns about flooding and landslides in Los Angeles, mostly in the Pacific Palisades neighbourhood, which was also hit by wildfires in January. Windspeeds gusting in excess of 100 km per hour have been recorded in San Francisco, where waves more than 7 m high have been reported. More than 100 000 people have been left without power due to the storms, mostly in the central part of the state.

The storms have been driven by a phenomenon called an atmospheric river, in which a narrow band of saturated air carries large volumes of moisture for long distances. Such streams typically originate in tropical regions, and typically travel along the boundaries between diverging weather systems. As with other storm systems, once they pass over land they lose momentum, and can be forced upwards by hills or mountains, causing them to cool and deposit their moisture as precipitation, causing high rainfall and often flooding.

A diagrammatic representation of an atmospheric river. National Weather Service/National Atmospheric and Oceanic Organization/Wikimedia Commons.

Atmospheric rivers are a common phenomenon on the west coast of the United States, and a significant driver of local weather conditions. However, these systems are becoming both more common and more severe as a result of the warming climate, which has led to rising temperatures over the tropical Pacific, and subsequently higher levels of atmospheric moisture, combined with a tendency form storm systems and other weather events to form and move much more quickly, making it harder for meteorologists to make long term predictions about where and when such storms will hit.

See also...

Magnitude 5.5 Earthquake in San Bernardino County, California.

The United States Geological Survey recorded a Magnitude 5.5 Earthquake at a depth of about 8.4 km beneath San Bernardion County, California, slightly after 1.30 am local time (slightly after 8.30 am GMT) on Thursday 4 June 2020. There are no reports of any damage or injuries relating to this quake, but people have reported feeling it across much of California, Arizona, southern Nevada, and parts of Beja California.

The approximate location of the 4 June 2020 San Bernardino County Earthquake. USGS.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

Tectonic boundaries and faults in California and the surrounding area. USGS.

Witness accounts of Earthquakes can help geologists to understand these events and the underlying structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.

See also...

Follow Sciency Thoughts on Facebook.

Cloud of Ladybird Beetles, confuse US Weather Radar.

A United States National Weather Service station in San Diego was briefly confused by the apparent sudden appearance of a large cloud over San Bernardino County, California. The cloud appeared without warning on the San Diego CA Radar system on Wednesday 5 June 2019, and appeared to be about 130 km across, far larger than would usually be expected to form rapidly over a fairly dry part of Southern California in June. This prompted the weather station to contact ground observers in the area, who reported a large cloud of the Beetles travelling at between 1500 and 2750 m, with the densest part of the cloud less than 20 km across.

Large cloud of Ladybird Beetles detected over Southern California by a weather radar system. National Weather Service.

Ladybird Beetles, Coccinellidae, are primarily carnivorous Beetles, many species targeting agricultural pests such as Aphids or Scale Insects, so that they are widely used as biological controls. though most species will eat some plant matter, and some are minor pests in their own right. Most species are red or orange in colour, often with conspicuous spots; the name 'Ladybird' refers to the apparent resemblance of the colour of the Beetles to the cloak of the Virgin Mary, which by convention was always depicted as red in classical European art, although many species have less conspicuous colouration, making them harder to identify as part of the group. Large clouds of Ladybirds are an uncommon phenomenon. usually associated with droughts, which can lead to shortages of prey items, causing large numbers of the Beetles to take to the air at the same time.

See also...

Follow Sciency Thoughts on Facebook.

Magnitude 3.7 Earthquake in San Bernardino County, California.

The United States Geological Survey recorded a Magnitude 3.7 Earthquake at a depth of about 14.1 km about 5 km to the south of Loma Linda in San Bernadino County, California, slightly before 10.45 pm local time on Saturday 8 October 2016 (slightly before 5.45 am on Sunday 9 October GMT). There are no reports of any damage or injuries relating to this quake, but people have reported feeling it acrossthe Los Angelese Basin and much of Southern California, from Santa Barbara in the coast east to Indio and south to Tijuana in Mexico.

The approximate location of the 8 October 2016 San Bernardino County Earthquake. Google.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

 The extent of and movement on the San Andreas Fault. Geology.

Witness accounts of Earthquakes can help geologists to understand these events and the underlying structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.

See also...

Magnitude 2.9 Earthquake in Orange County, California.                                                     The United States Geological Survey recorded a Magnitude 2.9 Earthquake at a depth of about 14.5 km about 3 km to the northwest of Seal Beach in Orange County, California,slightly before...

Sewage spill closes waterfront at Long Beech, California.                                       Parts of the harbour in Long Beech, Los Angeles, had to be closed off after a collapsed pipeline leaked about nine million liters of sewage into the Los Angeles...

 Magnitude 3.5 £qrthquake beneath northern Los Angeles.                                      The United States Geological Survey recorded a Magnitude 3.5 Earthquake at a depth of about 3 km beneath the Pacoima district of Los...

Follow Sciency Thoughts on Facebook. 

 

Magnitude 4.3 Earthquake in San Bernardino County, California.

The United States Geological Survey recorded a Magnitude 4.3 Earthquake at a depth of 1.9 km, in the western Mojave Desert about 40 km east of Newberry Springs in San Bernardino County, California, slightly after 7.05 pm local time on Saturday 5 October 2013 (slightly after 2.05 am on Sunday 6 October, GMT). There are no reports of any damage or injuries arising from this quake, but it was felt as far away as Los Angeles, 200 km southwest of the epicenter.

The approximate location of the 5 October 2013 San Bernardino Earthquake. Google Maps.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

Witness accounts of Earthquakes can help geologists to understand these events and the underlying structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.

See also Magnitude 3.0 Earthquake in Orange County, California, Magnitude 2.5 Earthquake in northwest San Benito County, California, Magnitude 2.5 Earthquake on the San Diego/Riverside County boundary, southern California, Magnitude 2.8 Earthquake in San Benito County, California and Two Earthquakes in Riverside County, southern California.

Follow Sciency Thoughts on Facebook.

Magnitude 2.5 Earthquake in San Bernardino County, California.

The United States Geological Survey recorded a Magnitude 2.5 Earthquake at a depth of 100 m, in San Bernardino County, California, 61 km to the north of Joshua Tree, slightly before 11.40 am local time (slightly before 6.40 pm GMT) on Sunday 15 September 2013. This is a small quake, unlikely to have caused any damage or casualties, particularly as it occurred in a remote location, though it may have been felt locally.

The approximate location of the 15 September 2013 San Bernardino County Earthquake. Google Maps.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

Witness accounts of Earthquakes can help geologists to understand these events and the underlying structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.

See also Magnitude 4.1 Earthquake in northeast Baja California, Magnitude 2.8 Earthquake in Baja California, Magnitude 3.6 Earthquake in Inyo County, northern California, Magnitude 3.1 Earthquake to the north of the Gulf of California and Magnitude 3.2 Earthquake in southern California.

Follow Sciency Thoughts on Facebook.