Alert archive / Nevada / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Las Vegas, NV

June 29, 2021Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jun 29, 2021, 2:29 PM PDT for Clark County, Nevada. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 29, 2021, 2:29 PM PDT (21:29 UTC)
Expired: Jun 29, 2021, 4:29 PM PDT
In force: 2 hr
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), 76 km from the middle of the area, began a volume at 21:32 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, 9.5 hours before the alert went out and 35 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: 41 J/kg
Mixed-layer CIN: -205 J/kg
Mixed-layer LCL: 3715 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 38 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

836 
WGUS55 KVEF 292129
FFWVEF
NVC003-300030-
/O.NEW.KVEF.FF.W.0002.210629T2129Z-210630T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
229 PM PDT Tue Jun 29 2021

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  Southwestern Clark County in southern Nevada...

* Until 530 PM PDT.

* At 229 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain along and to the north of Highway 160 west of Mountain 
  Spring Summit. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Doppler radar.

  IMPACT...Life-threatening flash flooding of low-water
           crossings, creeks, normally dry washes and roads.

* Some locations that will experience flash flooding include...
  Highway 160 west of the Mountain Spring Summit.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3615 11560 3609 11562 3603 11564 3600 11573
      3594 11567 3600 11553 3615 11551

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

SC

2 follow-up statements

582 
WGUS75 KVEF 292219
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
319 PM PDT Tue Jun 29 2021

NVC003-300030-
/O.CON.KVEF.FF.W.0002.000000T0000Z-210630T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
319 PM PDT Tue Jun 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM PDT THIS 
AFTERNOON FOR SOUTHWESTERN CLARK COUNTY...

At 319 PM PDT, Doppler radar indicated that the thunderstorms that 
produced heavy rain near Highway 160 have weakened. Flash flooding 
is still possible from runoff from the earlier heavy rainfall.

HAZARD...Life-threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Doppler radar.

IMPACT...Life-threatening flash flooding of low-water crossings,
         creeks, normally dry washes and roads.

Some locations that will experience flash flooding include...
  Highway 160 west of the Mountain Springs Summit.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3615 11560 3609 11562 3603 11564 3600 11573
      3594 11567 3600 11553 3615 11551

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

SC

187 
WGUS75 KVEF 292329
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
429 PM PDT Tue Jun 29 2021

NVC003-292339-
/O.CAN.KVEF.FF.W.0002.000000T0000Z-210630T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
429 PM PDT Tue Jun 29 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN CLARK COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

LAT...LON 3615 11560 3609 11562 3603 11564 3600 11573
      3594 11567 3600 11553 3615 11551

$$

SC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 29, 3:24 PM PDT	Severe Thunderstorm Warning	VEF	Lincoln	51 min
Jun 29, 3:26 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Lincoln	3 hr
Jun 29, 4:17 PM PDT	Severe Thunderstorm Warning	VEF	Clark, Lincoln	58 min

Nearby

Flash Flood Warnings in Nevada, 2021 Every flash flood warning in 2021

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.