Alert archive / California / Flash Flood Warnings in 2022

Flash Flood Warning 311, NWS Las Vegas, NV

September 28, 2022San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Sep 28, 2022, 12:05 PM PDT for San Bernardino County, California. It was in force for 3 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: Sep 28, 2022, 12:05 PM PDT (19:05 UTC)
Expired: Sep 28, 2022, 3:15 PM PDT
In force: 3 hr
Issued by: NWS Las Vegas, NV
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County San Bernardino County, CA

The radar

The Edwards AFB radar (KEYX), 129 km from the middle of the area, began a volume at 19:07 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, 7.1 hours before the alert went out and 246 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: 2402 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 1 m²/s²
0-3 km storm-relative helicity: 8 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 Las Vegas, NV wrote its last area forecast discussion before this flash flood warning went out at Sep 28, 10:05 AM PDT, 2 hours earlier.

Area forecast discussion, Sep 28, 10:05 AM PDT, 2 hours before

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The office that day

Everything else NWS Las Vegas, NV issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 28, 8:00 AM PDT	Areal Flood Advisory	VEF	Clark	2 hr
Sep 28, 11:10 AM PDT	Flash Flood Warning Considerable damage threat	VEF	Clark	3 hr
Sep 28, 2:35 PM PDT	Areal Flood Advisory	VEF	San Bernardino	3 hr

Nearby

Flash Flood Warnings in California, 2022 Every flash flood warning in 2022

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.