Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 43, NWS Las Vegas, NV

July 21, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Jul 21, 2021, 3:35 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: Jul 21, 2021, 3:35 PM MST (22:35 UTC)
Expired: Jul 21, 2021, 6:45 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), 73 km from the middle of the area, began a volume at 22:34 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, 10.6 hours before the alert went out and 162 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: 113 J/kg
Mixed-layer CIN: -279 J/kg
Mixed-layer LCL: 2504 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 19 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

139 
WGUS55 KVEF 212235
FFWVEF
AZC015-220145-
/O.NEW.KVEF.FF.W.0043.210721T2235Z-210722T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
335 PM PDT Wed Jul 21 2021

The National Weather Service in Las Vegas has issued a

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

* Until 645 PM MST.

* At 335 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned 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...
  Packsaddle Campground, Windy Point Campground, Stockton Hill Road, 
  and Chloride.

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.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3551 11404 3547 11408 3542 11414 3537 11419
      3535 11422 3541 11427 3547 11420 3556 11417
      3557 11406

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

$$

AN

1 follow-up statement

933 
WGUS75 KVEF 220135
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
635 PM PDT Wed Jul 21 2021

AZC015-220145-
/O.EXP.KVEF.FF.W.0043.000000T0000Z-210722T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
635 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 645 PM MST THIS EVENING FOR 
SOUTHWESTERN MOHAVE COUNTY...

The heavy rain has ended over the warned area. Flash Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

LAT...LON 3551 11404 3547 11408 3542 11414 3537 11419
      3535 11422 3541 11427 3547 11420 3556 11417
      3557 11406

$$

TB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 6:47 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 hr
Jul 21, 12:07 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	4 hr
Jul 21, 1:24 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	5 hr
Jul 21, 2:25 PM MST	Areal Flood Advisory	VEF	Mohave	2 hr
Jul 21, 4:03 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	2 hr
Jul 21, 4:18 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	2 hr
Jul 21, 4:56 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.