Alert archive / Nevada / Flash Flood Warnings in 2022

Flash Flood Warning 315, NWS Las Vegas, NV

September 29, 2022Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Sep 29, 2022, 2:23 PM PDT for Clark County, Nevada. It was in force for 55 min. 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 29, 2022, 2:23 PM PDT (21:23 UTC)
Expired: Sep 29, 2022, 3:18 PM PDT
In force: 55 min
Issued by: NWS Las Vegas, NV
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Clark County, NV

The radar

The Las Vegas radar (KESX), 58 km from the middle of the area, began a volume at 21:23 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

Las Vegas, NV (KVEF), launched 12:00Z, 9.4 hours before the alert went out and 50 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: 276 J/kg
Mixed-layer CIN: -194 J/kg
Mixed-layer LCL: 2357 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 8 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 29, 2:09 PM PDT, 14 minutes earlier.

Area forecast discussion, Sep 29, 2:09 PM PDT, 14 minutes before

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In the hours before

Local storm report, Sep 29, 9:25 AM PDT, 4 hours 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAS VEGAS NV
925 AM PDT THU SEP 29 2022

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

0230 PM     FLASH FLOOD      5 E JOSHUA TREE         34.14N 116.24W
09/28/2022                   SAN BERNARDINO     CA   LAW ENFORCEMENT

            HEAVY WATER AND DEBRIS ON STATE ROUTE 62
            BETWEEN ROTARY WAY AND WHITE FEATHER ROAD.
            TIME OF FLOODING ESTIMATED BY RADAR.

0307 PM     FLASH FLOOD      2 N JOSHUA TREE         34.17N 116.31W
09/28/2022                   SAN BERNARDINO     CA   LAW ENFORCEMENT

            VAN STUCK IN FLOWING WATER. INJURIES
            UNKNOWN. DRIVER UNABLE TO GET OUT.

0343 PM     FLASH FLOOD      3 N JOSHUA TREE         34.17N 116.31W
09/28/2022                   SAN BERNARDINO     CA   LAW ENFORCEMENT

            ROADWAY HEAVY WATER AND DEBRIS ON SUNBURST
            BETWEEN DENNIS AND GOLDEN.

&&

VARIAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 29, 12:06 PM PDT	Areal Flood Advisory	VEF	Clark	114 min
Sep 29, 2:06 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	114 min
Sep 28, 5:28 PM PDT	Flash Flood Warning	VEF	Mohave	3 hr
Sep 29, 12:36 PM PDT	Dust Storm Warning	VEF	Mohave	34 min
Sep 29, 1:07 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Mohave	113 min

Nearby

Flash Flood Warnings in Nevada, 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.