Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 127, NWS Las Vegas, NV

August 18, 2012Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 18, 2012, 4:56 PM MST for Mohave County, Arizona. It was in force for 2 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
Aug 18, 2012, 4:56 PM MST (23:56 UTC)
Expired
Aug 18, 2012, 7:00 PM MST
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Mohave County, AZ

The radar

The Las Vegas radar (KESX), 119 km from the middle of the area, began a volume at 23:56 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, 11.9 hours before the alert went out and 167 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.

465 
WGUS55 KVEF 182356
FFWVEF
AZC015-190200-
/O.NEW.KVEF.FF.W.0127.120818T2356Z-120819T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
456 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 700 PM MST.

* AT 448 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER CENTRAL MOHAVE COUNTY...OR
  34 MILES NORTHEAST OF KINGMAN. THE STORM PRODUCING VERY HEAVY RAIN
  WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  BUCK AND DOE ROAD NORTHWEST OF PEACH SPRINGS.  

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.

CAMPERS AND HIKERS SHOULD BE ALERT TO THE POSSIBILITY OF RAPIDLY
RISING WATER AND BE PREPARED TO MOVE QUICKLY TO HIGHER GROUND IF
FLASH FLOODING IS OBSERVED.

&&

LAT...LON 3567 11368 3567 11345 3551 11344 3546 11367

$$

ASG
2 follow-up statements
122 
WGUS75 KVEF 190050
FFSVEF

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

AZC015-190200-
/O.CON.KVEF.FF.W.0127.000000T0000Z-120819T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
550 PM MST SAT AUG 18 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 PM MST FOR
CENTRAL MOHAVE COUNTY...

AT 539 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A THUNDERSTORM PRODUCING VERY HEAVY RAIN.  THIS STORM WAS
LOCATED OVER CENTRAL MOHAVE COUNTY...OR 37 MILES NORTHEAST OF
KINGMAN. THE THUNDERSTORM WITH EXCESSIVE RAIN WAS NEARLY STATIONARY.

LOCATIONS IMPACTED INCLUDE...

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 3567 11368 3567 11345 3551 11344 3546 11367

$$

ASG
237 
WGUS75 KVEF 190155
FFSVEF

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

AZC015-190201-
/O.EXP.KVEF.FF.W.0127.000000T0000Z-120819T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
655 PM MST SAT AUG 18 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 700 PM MST FOR CENTRAL
MOHAVE COUNTY...

THE STORM THAT PRODUCED THE EARLIER HEAVY RAIN HAS DISSIPATED AND NO 
LONGER IS CONSIDERED A FLASH FLOOD THREAT. THEREFORE THE WARNING 
WILL BE ALLOWED TO EXPIRE AT 7 PM. MOTORISTS SHOULD CONTINUE TO BE 
ALERT TO PONDING OF WATER ON AREA ROADWAYS INCLUDING BUCK AND DOE 
ROAD NORTH OF STATE ROUTE 66 NEAR PEACH SPRINGS.

LAT...LON 3567 11368 3567 11345 3551 11344 3546 11367

$$

JS

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, 12:25 PM MSTFlash Flood WarningVEFMohave78 min
Aug 18, 2:43 PM MSTSevere Thunderstorm WarningVEFMohave47 min
Aug 18, 3:45 PM MSTFlash Flood WarningVEFMohave94 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.