Alert archive / California / Flash Flood Warnings in 2024

Flash Flood Warning 4, NWS Los Angeles, CA

February 4, 2024Los Angeles County, California

NWS Los Angeles, CA issued this flash flood warning at Feb 4, 2024, 3:41 PM PST for Los Angeles County, California. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Feb 4, 2024, 3:41 PM PST (23:41 UTC)
Expired
Feb 5, 2024, 12:00 AM PST
In force
8 hr
Issued by
NWS Los Angeles, CA
Area
Storm-based polygon
Flood severity
None

County Los Angeles County, CA

The radar

The Santa Ana Mts radar (KSOX), 71 km from the middle of the area, began a volume at 23:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Vandenberg AFB, CA (KVBG), launched 12:00Z, 11.7 hours before the alert went out and 214 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Vandenberg AFB, CA at 12:00Z on 2024-02-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Vandenberg AFB, CA at 12:00Z on 2024-02-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 696 square meters per square second.1939587897117136156Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
597 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
696 m²/s²
0-3 km storm-relative helicity
987 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Los Angeles, CA wrote its last area forecast discussion before this flash flood warning went out at Feb 4, 3:15 PM PST, 26 minutes earlier.

Area forecast discussion, Feb 4, 3:15 PM PST, 26 minutes before
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In the hours before

Local storm report, Feb 4, 12:40 PM PST, 3 hours 1 minute before
Preliminary Local Storm Report
National Weather Service Los Angeles/Oxnard CA
1240 PM PST Sun Feb 4 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0920 AM     Non-Tstm Wnd Gst 2 NNE Los Olivos        34.70N 120.10W
02/04/2024  M58 MPH          Santa Barbara      CA   Mesonet

            Mesonet station TT480 Sbcfd Portable 1.

1210 PM     Non-Tstm Wnd Gst 1 SE Santa Ynez         34.60N 120.09W
02/04/2024  M58 MPH          Santa Barbara      CA   Mesonet

            Mesonet station AP901 Santa Ynez.

0700 AM     Non-Tstm Wnd Gst Refugio State Beach     34.46N 120.08W
02/04/2024  M59 MPH          Santa Barbara      CA   Mesonet

            Mesonet station 623SE Sce Refugio Beach.

1000 AM     Non-Tstm Wnd Gst 3 ENE Cayucos           35.46N 120.86W
02/04/2024  M59 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG569 Whale Rock Rsvr (PGE).

1010 AM     Non-Tstm Wnd Gst 3 SW Guadalupe          34.93N 120.61W
02/04/2024  M59 MPH          Santa Barbara      CA   Mesonet

            Mesonet station 417PG Guadalupe.

1220 PM     Non-Tstm Wnd Gst 6 ENE Santa Margarita   35.41N 120.53W
02/04/2024  M59 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG190 Flying Lady Rd (PGE).

0900 AM     Non-Tstm Wnd Gst 5 W Lompoc              34.67N 120.55W
02/04/2024  M60 MPH          Santa Barbara      CA   Mesonet

            Mesonet station 449PG Renwick Ave.

0928 AM     Non-Tstm Wnd Gst 2 N Orcutt              34.90N 120.45W
02/04/2024  M60 MPH          Santa Barbara      CA   ASOS

            ASOS station KSMX Santa Maria Apt.

1120 AM     Non-Tstm Wnd Gst 1 E Big Pines           34.38N 117.66W
02/04/2024  M60 MPH          Los Angeles        CA   Mesonet

            Mesonet station SE547 Ford Observatory
            (SCE).

1210 PM     Non-Tstm Wnd Gst 5 NNE Goleta            34.50N 119.79W
02/04/2024  M60 MPH          Santa Barbara      CA   Mesonet

            Mesonet station 422SE Painted Cave Rd (SCE).

0902 AM     Non-Tstm Wnd Gst 3 SSE San Luis Obispo   35.23N 120.63W
02/04/2024  M61 MPH          San Luis Obispo    CA   ASOS

            ASOS station KSBP San Luis Obispo Apt.

0935 AM     Non-Tstm Wnd Gst 1 WSW Figueroa Mountain 34.73N 120.01W
02/04/2024  M61 MPH          Santa Barbara      CA   Mesonet

            Mesonet station FGMC1 Figueroa Mountain
            RAWS.

1020 AM     Non-Tstm Wnd Gst Gaviota                 34.47N 120.21W
02/04/2024  M61 MPH          Santa Barbara      CA   Mesonet

            Mesonet station SE239 Gaviota (SCE).

0819 AM     Non-Tstm Wnd Gst 4 SSW Lompoc            34.60N 120.49W
02/04/2024  M62 MPH          Santa Barbara      CA   Mesonet

            Mesonet station EW2332 Lompoc.

0950 AM     Non-Tstm Wnd Gst 2 WSW Santa Margarita   35.36N 120.66W
02/04/2024  M62 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG119 TV Towers (PGE).

1046 AM     Non-Tstm Wnd Gst 5 WSW Figueroa Mountain 34.73N 120.07W
02/04/2024  M62 MPH          Santa Barbara      CA   Mesonet

            Mesonet station TT594 Sbcfd Portable 2.

1150 AM     Non-Tstm Wnd Gst 3 WNW Refugio State Bea 34.48N 120.12W
02/04/2024  M62 MPH          Santa Barbara      CA   Mesonet

            Mesonet station 367SE Sce Coastal View.

1134 AM     Non-Tstm Wnd Gst 5 W Lompoc              34.67N 120.56W
02/04/2024  M63 MPH          Santa Barbara      CA   Mesonet

            Mesonet station TT414 Vandenberg Portable.

0930 AM     Non-Tstm Wnd Gst 10 WNW Gaviota          34.52N 120.38W
02/04/2024  M64 MPH          Santa Barbara      CA   Mesonet

            Mesonet station SE687 Dangemond (SCE).

1000 AM     Non-Tstm Wnd Gst 5 E Cambria             35.53N 121.00W
02/04/2024  M64 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG594 Green Valley Rd (PGE).

0900 AM     Non-Tstm Wnd Gst 8 SSW Lake Nacimiento   35.62N 120.92W
02/04/2024  M65 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG494 Adelaida Foothills
            (PGE).

1040 AM     Non-Tstm Wnd Gst 2 E Cayucos             35.45N 120.87W
02/04/2024  M66 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG741 Cayucos Road.

1150 AM     Non-Tstm Wnd Gst 8 W Gaviota             34.47N 120.36W
02/04/2024  M66 MPH          Santa Barbara      CA   Mesonet

            Mesonet station SE456 San Agustin (SCE).

0809 AM     Non-Tstm Wnd Gst 2 NW Gaviota            34.49N 120.24W
02/04/2024  M68 MPH          Santa Barbara      CA   Mesonet

            Mesonet station GVTC1 Gaviota Hills RAWS.

1000 AM     Non-Tstm Wnd Gst 2 NE Vandenberg Village 34.73N 120.44W
02/04/2024  M68 MPH          Santa Barbara      CA   Mesonet

            Mesonet station PG825 Divide-Cabrillo.

1020 AM     Non-Tstm Wnd Gst 1 N Morro Bay           35.38N 120.85W
02/04/2024  M68 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station 072PG Hillcrest Drive.

1010 AM     Non-Tstm Wnd Gst 7 E Black Mountain      35.38N 120.22W
02/04/2024  M69 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG775 Lewis Ranch Road.

1020 AM     Non-Tstm Wnd Gst 4 WNW Atascadero        35.50N 120.76W
02/04/2024  M69 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG191 El Monte Rd (PGE).

1135 AM     Non-Tstm Wnd Gst 10 SSW California Valle 35.19N 120.08W
02/04/2024  M70 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station BRHC1 Branch Mtn RAWS.

1040 AM     Non-Tstm Wnd Gst 12 NNE Los Alamos       34.92N 120.22W
02/04/2024  M71 MPH          Santa Barbara      CA   Mesonet

            Mesonet station PG611 Tepesquet Canyon Road.

1200 PM     Non-Tstm Wnd Gst 8 S Agua Dulce          34.39N 118.34W
02/04/2024  M71 MPH          Los Angeles        CA   Mesonet

            Mesonet station SE678 Magic Mtn Truck Trl
            (SCE).

1100 AM     Non-Tstm Wnd Gst 3 NNE Los Alamos        34.79N 120.26W
02/04/2024  M72 MPH          Santa Barbara      CA   Mesonet

            Mesonet station PG665 Cat Canyon Road.

1140 AM     Non-Tstm Wnd Gst 5 ENE Cayucos           35.49N 120.82W
02/04/2024  M72 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG633 Old Creek Road.

0950 AM     Non-Tstm Wnd Gst 7 N Cayucos             35.55N 120.91W
02/04/2024  M73 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG175 Camino Del Capitan
            (PGE).

0854 AM     Non-Tstm Wnd Gst 12 SE Point Arguello    34.45N 120.47W
02/04/2024  M74 MPH          Santa Barbara      CA   Mesonet

            Mesonet station XCPT Pt. Conception
            Lighthouse.

1210 PM     Non-Tstm Wnd Gst 2 ENE San Luis Obispo   35.28N 120.63W
02/04/2024  M75 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG807 High School Hill.

1000 AM     Non-Tstm Wnd Gst 4 NE San Luis Obispo    35.31N 120.60W
02/04/2024  M77 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG715 Mt. Lowe (PGE).

1044 AM     Non-Tstm Wnd Gst 4 E Vandenberg Village  34.71N 120.39W
02/04/2024  M77 MPH          Santa Barbara      CA   Mesonet

            Mesonet station PUSC1 Purisima Hills.

0920 AM     Non-Tstm Wnd Gst 7 SSW Lompoc            34.57N 120.50W
02/04/2024  M78 MPH          Santa Barbara      CA   Mesonet

            Mesonet station PG852 De La Concepcion.

1100 AM     Non-Tstm Wnd Gst 5 W Santa Margarita     35.39N 120.71W
02/04/2024  M79 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG223 TV Towers Rd 2 (PGE).

0920 AM     Non-Tstm Wnd Gst 3 SSW Atascadero        35.45N 120.71W
02/04/2024  M80 MPH          San Luis Obispo    CA   Mesonet

            Mesonet station PG210 Falcon Rd (PGE).

&&
Local storm report, Feb 4, 12:47 PM PST, 2 hours 54 minutes before
Preliminary Local Storm Report
National Weather Service Los Angeles/Oxnard CA
1247 PM PST Sun Feb 4 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1243 PM     Non-Tstm Wnd Dmg San Luis Obispo         35.27N 120.66W
02/04/2024                   San Luis Obispo    CA   Emergency Mngr

            Over 22,000 people were reported without
            power in San Luis Obispo county due to the
            strong winds.

1245 PM     Non-Tstm Wnd Dmg Santa Barbara           34.43N 119.72W
02/04/2024                   Santa Barbara      CA   Emergency Mngr

            Over 10,000 people were reported to have
            lost power in Santa Barbara county due to
            the strong winds.

&&
Local storm report, Feb 4, 2:06 PM PST, 1 hour 35 minutes before
Preliminary Local Storm Report
National Weather Service Los Angeles/Oxnard CA
206 PM PST Sun Feb 4 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0130 PM     Non-Tstm Wnd Dmg 2 E Santa Barbara       34.43N 119.69W
02/04/2024                   Santa Barbara      CA   Public

            Strong winds knocked down a tree, resulting
            in some downed power lines.

&&

The office that day

Everything else NWS Los Angeles, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 3, 4:35 PM PSTCoastal Flood AdvisoryLOXLos Angeles, Santa Barbara, Ventura40 hr
Feb 4, 10:14 AM PSTRiver Flood WarningLOXVentura14 hr
Feb 4, 12:05 PM PSTAreal Flood AdvisoryLOXSanta Barbara, Ventura5 hr
Feb 4, 1:04 PM PSTAreal Flood AdvisoryLOXVentura4 hr
Feb 4, 1:38 PM PSTAreal Flood AdvisoryLOXLos Angeles2 hr
Feb 4, 2:04 PM PSTAreal Flood AdvisoryLOXSan Luis Obispo, Santa Barbara3 hr
Feb 4, 2:17 PM PSTSpecial Marine WarningLOX69 min
Feb 4, 2:40 PM PSTFlash Flood WarningLOXSanta Barbara, Ventura9 hr
Feb 4, 2:58 PM PSTFlash Flood WarningLOXSan Luis Obispo, Santa Barbara8 hr
Feb 4, 3:23 PM PSTAreal Flood AdvisoryLOXLos Angeles88 min

Nearby

Flash Flood Warnings in California, 2024Every flash flood warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.