Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 95, NWS Las Vegas, NV

July 31, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Jul 31, 2021, 5:18 PM MST for Mohave County, Arizona. It was in force for 2 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 31, 2021, 5:18 PM MST (00:18 UTC)
Expired
Jul 31, 2021, 7:40 PM MST
In force
2 hr
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), 76 km from the middle of the area, began a volume at 00:18 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.

What was reported inside it

TimeReportWhereRemark
Jul 31, 5:20 PM MSTFLASH FLOOD11 Ne Dolan Springs, AZWATER FLOWING ACROSS STOCKTON HILL ROAD.
Jul 31, 6:15 PM MSTFLASH FLOOD15 Ne Dolan Springs, AZCOUNTY OFFICIALS CLOSED ANTARES ROAD FROM PIERCE FERRY ROAD TO HUNTINGTON AVENUE DUE TO FLASH FLOODING DAMAGE. A FOOT DEEP RUT HAS BEEN CARVED INTO THE ROAD DUE TO FLOOD WATERS. TIME AND LOCATION ESTIMATED BY RADAR AND NEARBY REPORTS. ROAD REMAINS CLOSED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 00:00Z, 0.3 hours before the alert went out and 157 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 00:00Z on 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 127 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 00:00Z on 2021-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 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
127 J/kg
Mixed-layer CIN
-127 J/kg
Mixed-layer LCL
2350 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

044 
WGUS55 KVEF 010018
FFWVEF
AZC015-010315-
/O.NEW.KVEF.FF.W.0095.210801T0018Z-210801T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
518 PM PDT Sat Jul 31 2021

The National Weather Service in Las Vegas has issued a

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

* Until 815 PM MST.

* At 518 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area, especially across portions 
  Stockton Hill Road. 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...
  Pierce Ferry And Antares Roads, Grand Canyon Ranch and Dolan 
  Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3547 11401 3546 11411 3557 11415 3577 11417
      3590 11416 3588 11398 3563 11380

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

$$

CP
1 follow-up statement
013 
WGUS75 KVEF 010240
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
740 PM PDT Sat Jul 31 2021

AZC015-010250-
/O.CAN.KVEF.FF.W.0095.000000T0000Z-210801T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
740 PM MST Sat Jul 31 2021

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL MOHAVE COUNTY...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 500 AM MST Sunday for 
portions of northwest Arizona, southeast California and Nevada.

LAT...LON 3547 11401 3546 11411 3557 11415 3577 11417
      3590 11416 3588 11398 3563 11380

$$

CP

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.