Alert archive / California / Flash Flood Warnings in 2023

Flash Flood Warning 4, NWS Los Angeles, CA

January 9, 2023Santa Barbara County, California

NWS Los Angeles, CA issued this flash flood warning at Jan 9, 2023, 2:57 PM PST for Santa Barbara County, California. It was in force for 4 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: Jan 9, 2023, 2:57 PM PST (22:57 UTC)
Expired: Jan 9, 2023, 6:45 PM PST
In force: 4 hr
Issued by: NWS Los Angeles, CA
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Santa Barbara County, CA

The radar

The Vandenberg AFB radar (KVBX), 47 km from the middle of the area, began a volume at 22:57 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, 11.0 hours before the alert went out and 48 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 494 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 428 m²/s²
0-3 km storm-relative helicity: 643 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 Jan 9, 2:23 PM PST, 34 minutes earlier.

Area forecast discussion, Jan 9, 2:23 PM PST, 34 minutes before

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In the hours before

Local storm report, Jan 9, 1:36 PM PST, 1 hour 21 minutes before

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Local storm report, Jan 9, 1:51 PM PST, 1 hour 6 minutes before

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Local storm report, Jan 9, 1:57 PM PST, 1 hour before

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Local storm report, Jan 9, 2:00 PM PST, 57 minutes before

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Local storm report, Jan 9, 2:33 PM PST, 24 minutes before

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Local storm report, Jan 9, 2:47 PM PST, 10 minutes before

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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
Jan 9, 4:57 AM PST	Areal Flood Advisory	LOX	Ventura	4 hr
Jan 9, 5:10 AM PST	Areal Flood Advisory	LOX	San Luis Obispo	4 hr
Jan 9, 5:38 AM PST	Areal Flood Advisory	LOX	Santa Barbara	14 hr
Jan 9, 9:29 AM PST	Areal Flood Advisory	LOX	San Luis Obispo	6 hr
Jan 9, 10:31 AM PST	Areal Flood Advisory	LOX	Ventura	4 hr
Jan 9, 10:56 AM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	6 hr
Jan 9, 10:56 AM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara, Ventura	6 hr
Jan 9, 11:36 AM PST	Areal Flood Warning	LOX	Ventura	17 hr
Jan 9, 1:56 PM PST	Areal Flood Warning	LOX	San Luis Obispo	19 hr
Jan 9, 2:32 PM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo, Santa Barbara	4 hr
Jan 9, 3:17 PM PST	Flash Flood Warning Considerable damage threat	LOX	Los Angeles, Ventura	6 hr

Nearby

Flash Flood Warnings in California, 2023 Every flash flood warning in 2023

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.