Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 41, NWS Las Vegas, NV

July 21, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Jul 21, 2021, 1:24 PM MST for Mohave County, Arizona. It was in force for 5 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, 1:24 PM MST (20:24 UTC)
Expired: Jul 21, 2021, 6:30 PM MST
In force: 5 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), 112 km from the middle of the area, began a volume at 20:24 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.4 hours before the alert went out and 191 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: 77 J/kg
Mixed-layer CIN: -129 J/kg
Mixed-layer LCL: 1785 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: -11 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

215 
WGUS55 KVEF 212024
FFWVEF
AZC015-212330-
/O.NEW.KVEF.FF.W.0041.210721T2024Z-210721T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  The Flag Burn Area in...
  Central Mohave County in northwestern Arizona...

* Until 430 PM MST.

* At 124 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Flag Burn Area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Flag Burn
           Area.

  SOURCE...Radar.

  IMPACT...Life-threatening flash flooding of areas in and around
           the Flag Burn Area.

* Some locations that will experience flash flooding include...
  Kingman, Pine Lake, and Hualapai Mountain Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life-threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of Wheeler Wash and other washes 
in and around Pine Lake and the Hualapai Mountain Park. Severe ash 
and debris flows can occur well downstream of the burn area which 
could potentially impact area roads. Watch for falling rocks. If you 
encounter flood waters...climb to safety.

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

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 3509 11383 3509 11381 3508 11384 3508 11385
      3508 11386 3508 11387 3507 11388 3508 11390
      3516 11408 3518 11405 3519 11401 3516 11393
      3512 11390 3510 11388 3509 11387 3509 11386
      3509 11385

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

$$

AN

3 follow-up statements

196 
WGUS75 KVEF 212134
FFSVEF

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

AZC015-212330-
/O.CON.KVEF.FF.W.0041.000000T0000Z-210721T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
234 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING FOR THE FLAG BURN AREA REMAINS IN EFFECT 
UNTIL 430 PM MST THIS AFTERNOON FOR CENTRAL MOHAVE COUNTY...

At 234 PM MST, Doppler radar and automated rain gauges indicated 
thunderstorms that produced heavy rain over the Flag Burn Area. 
Between 0.75 and 1.25 inches of rain have fallen according to rain 
gauges located on the Hualapai Mountain. The rainfall that prompted 
the warning has ended but drainage from this rainfall is likely 
still ongoing. Flash flooding is expected to continue.

HAZARD...Life-threatening flash flooding. Thunderstorms with
         heavy rainfall likely producing flash flooding in and
         around the Flag Burn Area.

SOURCE...Radar and automated gauges.

IMPACT...Life-threatening flash flooding of areas in and around
         the Flag Burn Area.

Some locations that will experience flash flooding include...
  Kingman and Hualapai Mountain Park.

Rainfall has currently ended but drainage flooding is likely still 
ongoing. If no additional development occurs before the end of the 
warning period, this warning will be allowed to expire.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life-threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of Wheeler Wash and other washes 
in and around Pine Lake and the Hualapai Mountain Park. Severe 
drainage and debris flows can occur well downstream of the burn area 
which could potentially impact area roads. Watch for falling rocks. 
If you encounter flood waters...climb to safety and if in a vehicle, 
turn around, don't drown.

&&

LAT...LON 3509 11383 3509 11381 3508 11384 3508 11385
      3508 11386 3508 11387 3507 11388 3508 11390
      3516 11408 3518 11405 3519 11401 3516 11393
      3512 11390 3510 11388 3509 11387 3509 11386
      3509 11385

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

$$

TB

587 
WGUS55 KVEF 212321
FFWVEF
AZC015-220130-
/O.EXT.KVEF.FF.W.0041.000000T0000Z-210722T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Las Vegas has extended the

* Flash Flood Warning for...
  The Flag Burn Area in...
  Central Mohave County in northwestern Arizona...

* Until 630 PM MST.

* At 421 PM MST, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain south of the Flag Burn Area 
  heading north. Between 0.75 and 1.25 inches of rain have already 
  fallen and an additional 0.5 to 1 inch are possible in the warned 
  area. Flash flooding is expected to continue.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Flag Burn
           Area.

  SOURCE...Radar and automated gauges.

  IMPACT...Life-threatening flash flooding of areas in and around
           the Flag Burn Area.

* Some locations that will experience flash flooding include...
  Kingman and Hualapai Mountain Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life-threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of Wheeler Wash and other washes 
in and around Pine Lake and the Hualapai Mountain Park. Severe ash 
and debris flows can occur well downstream of the burn area which 
could potentially impact area roads. Watch for falling rocks. If you 
encounter flood waters...climb to safety.

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

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 3509 11383 3509 11381 3508 11384 3508 11385
      3508 11386 3508 11387 3507 11388 3508 11390
      3516 11408 3518 11405 3519 11401 3516 11393
      3512 11390 3510 11388 3509 11387 3509 11386
      3509 11385

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

$$

TB

101 
WGUS75 KVEF 220122
FFSVEF

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

AZC015-220132-
/O.EXP.KVEF.FF.W.0041.000000T0000Z-210722T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
622 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING FOR THE FLAG BURN AREA WILL EXPIRE AT 630 PM 
MST THIS EVENING FOR CENTRAL MOHAVE COUNTY...

The heavy rain has ended and only light rain is expected over the 
next couple hours. Additional life-threatening flooding is no longer 
expected. Please continue to heed remaining road closures as runoff 
may be continuing in this area.

LAT...LON 3509 11383 3509 11381 3508 11384 3508 11385
      3508 11386 3508 11387 3507 11388 3508 11390
      3516 11408 3518 11405 3519 11401 3516 11393
      3512 11390 3510 11388 3509 11387 3509 11386
      3509 11385

$$

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, 2:25 PM MST	Areal Flood Advisory	VEF	Mohave	2 hr
Jul 21, 3:35 PM MST	Flash Flood Warning Considerable damage threat	VEF	Mohave	3 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.