CW3E Event Summary: 4-6 February 2024

14 February 2024

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Major CA Winter Storm (4-6 Feb 2024)

Overall summary:

  • A strong atmospheric river (AR) impacted much of California on 4-6 Feb 2024.
  • It was an AR3 in the Santa Barbara base on the Ralph (2019) AR scale.

Precipitation impacts:

  • Widespread precipitation of 1-5” fell across most of California with 5-10” in the coastal mountains and Los Angeles Basin. Some areas of the San Gabriel Mountains received 10-15” of precipitation.
  • Los Angeles recorded one of its wettest multi-day stretches on record.
  • Heavy rain resulted in hundreds of mudslides and high flows on area rivers.
  • Year-to-date percent of normal snowfall increased by 10-20% across the Sierra Nevada mountains.

Wind and power outages:

    • Storm produced widespread winds of 60+ mph across northern California with local peak wind gusts around the San Francisco Bay Area of 80-100 mph.
    • Strong winds and wet soils felled hundreds of trees.
    • A reported 1.4 million customers were without power at various points across the state.


Summary slide

IVT across the northeast Pacific Ocean during this event

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IVT near the US West Cost during this event

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Peak IVT values for this AR

Water vapor satellite loop of the event

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Radar loop of the event

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AR Recon IOP 31 map

CW3E Radiosondes

MSLP analysis of bomb cyclone

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Wind gust analysis

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Peak wind gusts

Total precipitation and share of annual rainfall

Chance in WYTD percent of normal precipitation

Chance in WYTD percent of normal precipitation LA area

Rainfall statistics for downtown LA

Snowfall analysis

Summary of impacts

Images of trees toppled

Images of landslides

Images of flooding

River gage data for the Los Angeles River

Images of snowfall

Example of FIRO operations

Summary provided by: P. Iniguez, C. Castellano, J. Cordeira, , J. Kalansky, S. Roj, and M. Steen.

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