Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 121, NWS Las Vegas, NV

August 18, 2012Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 18, 2012, 12:25 PM MST for Mohave County, Arizona. It was in force for 78 min. 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 18, 2012, 12:25 PM MST (19:25 UTC)
Expired
Aug 18, 2012, 1:43 PM MST
In force
78 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Mohave County, AZ

The radar

The Las Vegas radar (KESX), 113 km from the middle of the area, began a volume at 19:28 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, 7.4 hours before the alert went out and 189 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, Flgstf/Belemont, AZ at 12:00Z on 2012-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 124 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2012-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
124 J/kg
Mixed-layer CIN
-135 J/kg
Mixed-layer LCL
1298 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
-13 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

050 
WGUS55 KVEF 181925
FFWVEF
AZC015-182130-
/O.NEW.KVEF.FF.W.0121.120818T1925Z-120818T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1225 PM MST SAT AUG 18 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL MOHAVE COUNTY IN NORTHWEST ARIZONA...

* UNTIL 230 PM MST.

* AT 1215 PM MST...TRAINED WEATHER SPOTTERS REPORTED FLASH FLOODING
  FROM A THUNDERSTORM NEAR HUALAPAI MOUNTAIN PARK...OR 11 MILES      
  SOUTHEAST OF KINGMAN...MOVING NORTHEAST AT 10 MPH. AN AUTOMATED    
  GAGE NEAR HUALAPAI MOUNTAIN ROAD HAS REPORTED 1.10 INCHES IN THE   
  PAST HOUR.

* LOCATIONS IMPACTED INCLUDE...HUALAPAI MOUNTAIN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO CROSS A FLOODED
ROADWAY OR WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3516 11389 3511 11373 3500 11387 3513 11397

$$

PIERCE
2 follow-up statements
089 
WGUS75 KVEF 182002
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
102 PM MST SAT AUG 18 2012

AZC015-182130-
/O.CON.KVEF.FF.W.0121.000000T0000Z-120818T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
102 PM MST SAT AUG 18 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 230 PM MST FOR
CENTRAL MOHAVE COUNTY...

AT 1250 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
THUNDERSTORM WEAKENING AS IT NEARS INTERSTATE 40 EAST OF KINGMAN.  
THIS STORM WAS LOCATED NEAR HUALAPAI MOUNTAIN PARK...OR 12 MILES 
EAST OF KINGMAN...MOVING EAST AT 10 MPH. HEAVY RAIN HAS LEAD TO 
FLASH FLOODING OF NORMALLY DRY WASHES AND DRAINAGES IN THE AREA. 
WATER ACROSS HUALAPAI MOUNTAIN ROAD NEAR MILE MARKER 10 IS SLOWING 
ACCESS TO AND FROM HUALAPAI MOUNTAIN PARK.  

LOCATIONS IMPACTED INCLUDE...HUALAPAI MOUNTAIN ROAD...HUALAPAI 
MOUNTAIN PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO CROSS A FLOODED
ROADWAY OR WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3516 11389 3511 11373 3500 11387 3513 11397

$$

PIERCE
190 
WGUS75 KVEF 182043
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
143 PM MST SAT AUG 18 2012

AZC015-182051-
/O.CAN.KVEF.FF.W.0121.000000T0000Z-120818T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
143 PM MST SAT AUG 18 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR CENTRAL MOHAVE
COUNTY...

THE THUNDERSTORM THAT PRODUCED FLASH FLOODING ON HUALAPAI MOUNTAIN 
HAS WEAKENED. RUNOFF IN NORMALLY DRY WASHES AND SMALL DRAINAGE AREAS 
ON HUALAPAI MOUNTAIN HAVE RECEDED. THE FLASH FLOOD WARNING HAS BEEN 
CANCELLED.

LAT...LON 3516 11389 3511 11373 3500 11387 3513 11397

$$

PIERCE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 6:21 PM MSTAreal Flood AdvisoryVEFMohave106 min
Aug 18, 2:43 PM MSTSevere Thunderstorm WarningVEFMohave47 min
Aug 18, 3:45 PM MSTFlash Flood WarningVEFMohave94 min
Aug 18, 4:56 PM MSTFlash Flood WarningVEFMohave2 hr

Nearby

Flash Flood Warnings in Arizona, 2012Every flash flood warning in 2012

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.