Alert archive / California / Flash Flood Warnings in 2024

Flash Flood Warning 10, 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, 8:50 PM PST for Los Angeles County, Ventura County, California. It was in force for 13 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, 8:50 PM PST (04:50 UTC)
Expired: Feb 6, 2024, 10:00 AM PST
In force: 13 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 04:51 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 00:00Z, 4.8 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 438 m above ground
0-6 km bulk shear: 72 kt
0-1 km storm-relative helicity: 132 m²/s²
0-3 km storm-relative helicity: 198 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, 8:50 PM PST, 0 minutes earlier.

Area forecast discussion, Feb 5, 8:50 PM PST, 0 minutes before

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In the hours before

Local storm report, Feb 5, 4:10 PM PST, 4 hours 40 minutes before

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Local storm report, Feb 5, 4:11 PM PST, 4 hours 39 minutes before

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Local storm report, Feb 5, 4:17 PM PST, 4 hours 33 minutes before

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Local storm report, Feb 5, 4:41 PM PST, 4 hours 9 minutes before

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Local storm report, Feb 5, 4:43 PM PST, 4 hours 7 minutes before

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Local storm report, Feb 5, 5:09 PM PST, 3 hours 41 minutes before

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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 5, 4:18 PM PST	Areal Flood Advisory	LOX	Los Angeles, Santa Barbara, Ventura	16 hr
Feb 5, 5:34 PM PST	Areal Flood Advisory	LOX	Santa Barbara	8 hr
Feb 5, 7:17 PM PST	Areal Flood Advisory	LOX	San Luis Obispo	5 hr
Feb 5, 8:08 PM PST	Small Craft Advisory	LOX		6 hr
Feb 6, 1:53 AM PST	Areal Flood Advisory	LOX	Santa Barbara	4 hr
Feb 6, 2:24 AM PST	Small Craft Advisory	LOX		4 days
Feb 6, 8:30 AM PST	Special Weather Statement	LOX	Los Angeles	60 min
Feb 6, 9:11 AM PST	Coastal Flood Advisory	LOX	San Luis Obispo, Santa Barbara, Ventura	50 hr
Feb 6, 9:11 AM PST	High Surf Advisory	LOX	Los Angeles, San Luis Obispo, Santa Barbara, Ventura	3 days
Feb 6, 9:24 AM PST	Flash Flood Warning Considerable damage threat	LOX	Los Angeles	3 hr

Nearby

Flash Flood Warnings in California, 2024 Every 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.