Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 138, NWS Las Vegas, NV

August 20, 2012Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 20, 2012, 8:01 PM MST for Mohave County, Arizona. It was in force for 119 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 20, 2012, 8:01 PM MST (03:01 UTC)
Expired
Aug 20, 2012, 10:00 PM MST
In force
119 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), 88 km from the middle of the area, began a volume at 03:01 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.

What was reported inside it

TimeReportWhereRemark
Aug 20, 8:08 PM MSTHEAVY RAIN 02 Sw Kingman, AZTRAINED SPOTTER REPORTED VERY HEAVY RAIN AND 4 INCHES OF WATER ON HUALAPAI ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 00:00Z, 3.0 hours before the alert went out and 181 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, Las Vegas, NV at 00:00Z on 2012-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 633 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Las Vegas, NV at 00:00Z on 2012-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.193958Sfc1 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
633 J/kg
Mixed-layer CIN
-150 J/kg
Mixed-layer LCL
2388 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
30 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.

483 
WGUS55 KVEF 210301
FFWVEF
AZC015-210500-
/O.NEW.KVEF.FF.W.0138.120821T0301Z-120821T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
801 PM MST MON AUG 20 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 1000 PM MST.

* AT 753 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR GOLDEN VALLEY AND         
  KINGMAN. THE STORM PRODUCING VERY HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  GOLDEN VALLEY AND KINGMAN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. 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 3530 11424 3531 11400 3518 11395 3519 11408
      3515 11409 3517 11421

$$

JS
2 follow-up statements
433 
WGUS75 KVEF 210410
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
910 PM MST MON AUG 20 2012

AZC015-210500-
/O.CON.KVEF.FF.W.0138.000000T0000Z-120821T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
910 PM MST MON AUG 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1000 PM MST FOR
CENTRAL MOHAVE COUNTY...

AT 857 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A THUNDERSTORM PRODUCING MODERATE TO HEAVY RAIN WITH RADAR 
RAINFALL ESTIMATES OF GREATER THAN ONE INCH IN THE PAST HOUR. RAIN 
GAGE AMOUNTS OF A HALF INCH OR MORE WERE REPORTED IN A 30 MINUTE 
PERIOD. THIS STORM WAS LOCATED OVER KINGMAN AND WAS NEARLY 
STATIONARY.

LOCATIONS IMPACTED INCLUDE...
GOLDEN VALLEY...KINGMAN...ANDY DEVINE ROAD...STOCKTON ROAD AND 
HIGHWAY 93 IN OR NEAR KINGMAN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. 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 3530 11424 3531 11400 3518 11395 3519 11408
      3515 11409 3517 11421

$$

JS
814 
WGUS75 KVEF 210506
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1006 PM MST MON AUG 20 2012

AZC015-210513-
/O.EXP.KVEF.FF.W.0138.000000T0000Z-120821T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
1006 PM MST MON AUG 20 2012

...THE FLASH FLOOD WARNING HAS EXPIRED FOR CENTRAL MOHAVE COUNTY...

RAIN HAS ENDED IN THE WARNED AREA AND THE WARNING IS NO LONGER IN 
EFFECT. HOWEVER...FLOODING RELATED PROBLEMS WILL CONTINUE THROUGH 
THE EVENING WITH SOME ROADS REMAINING IMPASSABLE DUE TO THE FLOOD 
WATERS. MOTORISTS ARE URGED TO AVOID FLOODED AREAS UNTIL WATER HAS 
RECEDED.

LAT...LON 3530 11424 3531 11400 3518 11395 3519 11408
      3515 11409 3517 11421

$$

JS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 5:51 PM MSTSevere Thunderstorm WarningVEFMohave39 min
Aug 20, 6:09 PM MSTFlash Flood WarningVEFMohave2 hr
Aug 20, 7:37 PM MSTFlash Flood WarningVEFMohave4 hr
Aug 21, 11:39 AM MSTFlash Flood WatchVEFMohave36 hr
Aug 21, 1:43 PM MSTSevere Thunderstorm WarningVEFMohave32 min
Aug 21, 3:16 PM MSTFlash Flood WarningVEFMohave119 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.