Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 123, NWS Las Vegas, NV

August 30, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 30, 2021, 4:30 PM MST for Mohave County, Arizona. It was in force for 100 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 30, 2021, 4:30 PM MST (23:30 UTC)
Expired
Aug 30, 2021, 6:10 PM MST
In force
100 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Mohave County, AZ

The radar

The Las Vegas radar (KESX), 81 km from the middle of the area, began a volume at 23:33 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, 11.5 hours before the alert went out and 137 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-pSkew-T log-p diagram, Las Vegas, NV at 12:00Z on 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 37 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Las Vegas, NV at 12:00Z on 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -27 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
37 J/kg
Mixed-layer CIN
-324 J/kg
Mixed-layer LCL
3297 m above ground
0-6 km bulk shear
2 kt
0-1 km storm-relative helicity
-27 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

371 
WGUS55 KVEF 302330
FFWVEF
AZC015-310230-
/O.NEW.KVEF.FF.W.0123.210830T2330Z-210831T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
430 PM PDT Mon Aug 30 2021

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  Northwestern Mohave County in northwestern Arizona...

* Until 730 PM MST.

* At 430 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Meadview area. Flash flooding is ongoing or 
  expected to begin shortly.

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

  SOURCE...Radar.

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

* Some locations that will experience flash flooding include...
  Meadview.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

&&

LAT...LON 3605 11411 3605 11403 3594 11403 3595 11412

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

$$

CM
1 follow-up statement
050 
WGUS75 KVEF 310110
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
610 PM PDT Mon Aug 30 2021

AZC015-310120-
/O.CAN.KVEF.FF.W.0123.000000T0000Z-210831T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
610 PM MST Mon Aug 30 2021

...FLASH FLOOD WARNING IS CANCELLED FOR MEADVIEW IN NORTHWESTERN 
MOHAVE COUNTY...

The heavy rain that occurred around Meadview earlier this afternoon 
has not resulted in any flooding impacts and the Flash Flood Warning 
has been cancelled.

LAT...LON 3605 11411 3605 11403 3594 11403 3595 11412

$$

JA

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 5:42 PM MSTSevere Thunderstorm WarningVEFMohave48 min
Aug 30, 3:28 AM MSTFlash Flood WatchVEFMohave59 hr
Aug 30, 4:35 PM MSTFlash Flood Warning Considerable damage threatVEFMohave3 hr

Nearby

Flash Flood Warnings in Arizona, 2021Every 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.