Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 141, NWS Las Vegas, NV

August 21, 2012Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 21, 2012, 3:16 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 21, 2012, 3:16 PM MST (22:16 UTC)
Expired
Aug 21, 2012, 5:15 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), 138 km from the middle of the area, began a volume at 22:18 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 21, 4:15 PM MSTFLASH FLOOD5 Nnw Peach Springs, AZTHE HUALAPAI LODGE REPORTED THAT DIAMOND CREEK ROAD WAS COMPLETELY WASHED OUT DUE TO FLASH FLOODING FROM THE PEACH SPRINGS TURNOFF ALL THE WAY TO THE COLORADO RIVER. THE ROAD HAS BEEN CLOSED.

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

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 10.3 hours before the alert went out and 154 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 2012-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 465 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 2012-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 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
465 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
1171 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
1 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.

019 
WGUS55 KVEF 212216
FFWVEF
AZC015-220015-
/O.NEW.KVEF.FF.W.0141.120821T2216Z-120822T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
316 PM MST TUE AUG 21 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 515 PM MST.

* AT 309 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
VERY HEAVY RAIN FROM A CLUSTER OF THUNDERSTORMS NORTH OF STATE ROUTE 
66 IN EASTERN MOHAVE COUNTY NEAR DIAMOND CREEK CAMPGROUND. THE 
THUNDERSTORM PRODUCING VERY HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...DIAMOND CREEK ROAD AND DIAMOND CREEK 
CAMPGROUND.

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 3584 11332 3581 11331 3553 11333 3551 11349
      3587 11351 3589 11331 3584 11331

$$

KENNEDY
2 follow-up statements
350 
WGUS75 KVEF 212321
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
421 PM MST TUE AUG 21 2012

AZC015-220015-
/O.CON.KVEF.FF.W.0141.000000T0000Z-120822T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
421 PM MST TUE AUG 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 515 PM MST FOR
CENTRAL MOHAVE COUNTY...

AT 414 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE STRONG THUNDERSTORMS PRODUCING VERY HEAVY ALONG DIAMOND 
CREEK ROAD NEAR DIAMOND CREEK CAMPGROUND AND PEACH SPRINGS. LOCAL 
LAW ENFORCEMENT HAVE NOT YET RECEIVED ANY REPORTS OF FLASH 
FLOODING...BUT DID REPORT LONG PERIODS OF HEAVY RAIN IN THE AREA.

LOCATIONS IMPACTED INCLUDE...DIAMOND CREEK CAMPGROUND...DIAMOND 
CREEK ROAD...PEACH SPRINGS...AND ROUTE 66 NEAR PEACH SPRINGS.

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 3584 11332 3581 11331 3553 11333 3551 11349
      3587 11351 3589 11331 3584 11331

$$

KENNEDY
825 
WGUS75 KVEF 220017
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
517 PM MST TUE AUG 21 2012

AZC015-220021-
/O.EXP.KVEF.FF.W.0141.000000T0000Z-120822T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
517 PM MST TUE AUG 21 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 515 PM MST FOR CENTRAL
MOHAVE COUNTY...

THE THUNDERSTORMS WHICH PRODUCED THE HEAVY RAIN NORTH OF ROUTE 66 
OVER DIAMOND CREEK ROAD AND DIAMOND CREEK HAVE DISSIPATED AND THE 
WARNING WILL BE ALLOWED TO EXPIRE. THE HUALAPAI LODGE ALONG ROUTE 66 
HAS REPORTED THAT DIAMOND CREEK ROAD HAS BEEN CLOSED...AS THE ROAD 
HAS COMPLETELY BEEN WASHED OUT DUE TO FLASH FLOODING.


LAT...LON 3584 11332 3581 11331 3553 11333 3551 11349
      3587 11351 3589 11331 3584 11331

$$

KENNEDY

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 20, 8:01 PM MSTFlash Flood WarningVEFMohave119 min
Aug 21, 11:39 AM MSTFlash Flood WatchVEFMohave36 hr
Aug 21, 1:43 PM MSTSevere Thunderstorm WarningVEFMohave32 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.