Alert archive / California / Flash Flood Warnings in 2024

Flash Flood Warning 9, NWS Los Angeles, CA

February 5, 2024Los Angeles County, Ventura County, California

NWS Los Angeles, CA issued this flash flood warning at Feb 5, 2024, 1:08 PM PST for Los Angeles County, Ventura 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 5, 2024, 1:08 PM PST (21:08 UTC)
Expired
Feb 5, 2024, 9:00 PM PST
In force
8 hr
Issued by
NWS Los Angeles, CA
Area
Storm-based polygon
Flood severity
None

Counties Los Angeles County, CA, Ventura County, CA

The radar

The Los Angeles radar (KVTX), 47 km from the middle of the area, began a volume at 21:13 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

San Diego, CA (KNKX), launched 12:00Z, 9.1 hours before the alert went out and 215 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, San Diego, CA at 12:00Z on 2024-02-05Temperature 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, San Diego, CA at 12:00Z on 2024-02-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 259 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
1067 m above ground
0-6 km bulk shear
72 kt
0-1 km storm-relative helicity
259 m²/s²
0-3 km storm-relative helicity
304 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 5, 9:28 AM PST, 3 hours 40 minutes earlier.

Area forecast discussion, Feb 5, 9:28 AM PST, 3 hours 40 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Feb 4, 4:42 PM PSTAreal Flood AdvisoryLOXLos Angeles, Ventura7 hr
Feb 4, 4:51 PM PSTFlash Flood WarningLOXLos Angeles7 hr
Feb 4, 5:02 PM PSTAreal Flood AdvisoryLOXSan Luis Obispo7 hr
Feb 4, 5:50 PM PSTSmall Craft AdvisoryLOX19 hr
Feb 4, 6:16 PM PSTWind AdvisoryLOXLos Angeles, Ventura4 hr
Feb 4, 10:42 PM PSTAreal Flood AdvisoryLOXSan Luis Obispo, Santa Barbara5 hr
Feb 4, 11:38 PM PSTFlash Flood Warning Considerable damage threatLOXLos Angeles9 hr
Feb 4, 11:41 PM PSTAreal Flood AdvisoryLOXVentura9 hr
Feb 4, 11:56 PM PSTAreal Flood AdvisoryLOXLos Angeles9 hr
Feb 5, 1:13 AM PSTFlash Flood WarningLOXLos Angeles, Ventura8 hr
Feb 5, 9:40 AM PSTFlash Flood WarningLOXLos Angeles, Ventura11 hr
Feb 5, 10:13 AM PSTAreal Flood AdvisoryLOXLos Angeles, Ventura39 hr
Feb 5, 2:46 PM PSTWinter Weather AdvisoryLOXLos Angeles, Santa Barbara, Ventura65 hr

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.