Alert archive / Arizona / Flash Flood Watches in 2021

Flash Flood Watch 2, NWS Las Vegas, NV

July 14, 2021Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood watch at Jul 14, 2021, 10:59 AM MST for Mohave County, Arizona. It took effect at Jul 14, 2021, 1:00 PM MST. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued: Jul 14, 2021, 10:59 AM MST (17:59 UTC)
In effect from: Jul 14, 2021, 1:00 PM MST
Expired: Jul 15, 2021, 12:00 AM MST
In force: 11 hr
Issued by: NWS Las Vegas, NV
Flood severity: None

County Mohave County, AZ

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 6.0 hours before the alert went out and 177 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: 448 J/kg
Mixed-layer CIN: -374 J/kg
Mixed-layer LCL: 2057 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -19 m²/s²
0-3 km storm-relative helicity: 14 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

805 
WGUS65 KVEF 141759
FFAVEF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Las Vegas NV
1059 AM PDT Wed Jul 14 2021

AZZ001-150700-
/O.NEW.KVEF.FF.A.0002.210714T2000Z-210715T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
Including the cities of Western Grand Canyon, Mt Trumbull, Colorado 
City, Tuweep, and Pipe Spring National Monument
1059 AM MST Wed Jul 14 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH THIS EVENING...

The National Weather Service in Las Vegas has issued a

* Flash Flood Watch for a portion of northwest Arizona, including 
  the following area, Northwest Plateau.

* Through this evening.

* Thunderstorms that develop over eastern Nevada and southwest Utah 
  this afternoon are forecast to move south into northern Mohave 
  County early this evening. Rainfall rates up to 1 inch an hour are 
  possible which could trigger flash flooding of normally dry washes 
  and roadways.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

BKP

1 follow-up statement

905 
WGUS65 KVEF 150654
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
1154 PM PDT Wed Jul 14 2021

AZZ001-150800-
/O.EXP.KVEF.FF.A.0002.000000T0000Z-210715T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
Including the cities of Western Grand Canyon, Mt Trumbull, Colorado 
City, Tuweep, and Pipe Spring National Monument
1154 PM MST Wed Jul 14 2021

...FLASH FLOOD WATCH WILL EXPIRE AT MIDNIGHT MST TONIGHT...

The Flash Flood Watch for the Northwest Plateau will expire at 
Midnight MST tonight.

Flash Flooding is no longer expected to pose a threat for this area. 
Please continue to heed remaining road closures.

$$

TB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 13, 7:24 PM MST	Severe Thunderstorm Warning	VEF	Mohave	96 min
Jul 13, 8:29 PM MST	Severe Thunderstorm Warning	VEF	Mohave	91 min
Jul 13, 8:52 PM MST	Severe Thunderstorm Warning	VEF	Mohave	53 min

Nearby

Flash Flood Watches in Arizona, 2021 Every flash flood watch 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.