Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 98, NWS Las Vegas, NV

August 10, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 10, 2021, 12:30 PM MST for Mohave County, Arizona. 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 outline as issued.

The facts

Issued: Aug 10, 2021, 12:30 PM MST (19:30 UTC)
Expired: Aug 10, 2021, 3:30 PM MST
In force: 3 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), 103 km from the middle of the area, began a volume at 19:35 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, 7.5 hours before the alert went out and 169 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: 6 J/kg
Mixed-layer CIN: -327 J/kg
Mixed-layer LCL: 3246 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -14 m²/s²
0-3 km storm-relative helicity: 22 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

690 
WGUS55 KVEF 101930
FFWVEF
AZC015-102230-
/O.NEW.KVEF.FF.W.0098.210810T1930Z-210810T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
1230 PM PDT Tue Aug 10 2021

The National Weather Service in Las Vegas has issued a

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

* Until 330 PM MST.

* At 1230 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain along and to the east of Buck and Doe 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...
  mainly rural areas of Central Mohave County

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3599 11377 3593 11372 3586 11365 3575 11357
      3561 11375 3587 11398 3593 11395

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

$$

SC

2 follow-up statements

215 
WGUS75 KVEF 102049
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
149 PM PDT Tue Aug 10 2021

AZC015-102230-
/O.CON.KVEF.FF.W.0098.000000T0000Z-210810T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
149 PM MST Tue Aug 10 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 PM MST THIS 
AFTERNOON FOR CENTRAL MOHAVE COUNTY...

At 149 PM MST, Doppler radar indicated thunderstorms have diminished 
along Buck and Doe Road north of Meriwhitica Road. However, doppler 
radar estimates between 1 and 1.5 inches of rain have fallen with 
the earlier storms. Runoff from these earlier storms is still likely 
producing flash flooding.

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.

Buck and Doe Road north of Meriwhitica Road

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3599 11377 3593 11372 3586 11365 3575 11357
      3561 11375 3587 11398 3593 11395

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

$$

SC

125 
WGUS75 KVEF 102226
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
326 PM PDT Tue Aug 10 2021

AZC015-102236-
/O.EXP.KVEF.FF.W.0098.000000T0000Z-210810T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
326 PM MST Tue Aug 10 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 330 PM MST THIS AFTERNOON FOR 
CENTRAL MOHAVE COUNTY...

The heavy rain has ended has ended along Buck and Doe Road. Flooding 
is no longer expected to pose a threat. Please continue to heed 
remaining road closures.

LAT...LON 3599 11377 3593 11372 3586 11365 3575 11357
      3561 11375 3587 11398 3593 11395

$$

SC

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 1:22 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	2 hr
Aug 10, 1:35 PM MST	Severe Thunderstorm Warning	VEF	Mohave	40 min
Aug 10, 2:05 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Aug 10, 2:06 PM MST	Dust Storm Warning	VEF	Mohave	54 min
Aug 10, 2:13 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Aug 10, 2:50 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Aug 10, 3:25 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Aug 10, 3:51 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Aug 10, 4:59 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr

Nearby

Flash Flood Warnings in Arizona, 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.