Alert archive / Nevada / Flash Flood Warnings in 2011

Flash Flood Warning 81, NWS Las Vegas, NV

September 11, 2011Clark County, Lincoln County, Nye County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Sep 11, 2011, 3:27 PM PDT for Clark County, Lincoln County, Nye County, Nevada. 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
Sep 11, 2011, 3:27 PM PDT (22:27 UTC)
Expired
Sep 11, 2011, 5:30 PM PDT
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

Counties Clark County, NV, Lincoln County, NV, Nye County, NV

The radar

The Las Vegas radar (KESX), 157 km from the middle of the area, began a volume at 22:30 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

Las Vegas, NV (KVEF), launched 12:00Z, 10.5 hours before the alert went out and 62 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 12:00Z on 2011-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 10 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 12:00Z on 2011-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.19395878Sfc1 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
10 J/kg
Mixed-layer CIN
-244 J/kg
Mixed-layer LCL
1944 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
164 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.

740 
WGUS55 KVEF 112227
FFWVEF
NVC003-017-023-120030-
/O.NEW.KVEF.FF.W.0081.110911T2227Z-110912T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
327 PM PDT SUN SEP 11 2011

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EXTREME SOUTHWESTERN LINCOLN COUNTY IN SOUTH CENTRAL NEVADA...
  SOUTH CENTRAL NYE COUNTY IN SOUTH CENTRAL NEVADA...
  NORTHWESTERN CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 530 PM PDT.

* AT 325 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER EXTREME NORTHWESTERN CLARK
  COUNTY...OR 13 MILES NORTHEAST OF MERCURY. THE STORM PRODUCING VERY
  HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME NORTHWESTERN CLARK...EXTREME 
  SOUTHWESTERN LINCOLN AND SOUTHERN NYE COUNTIES...INCLUDING THE 
  NEVADA NATIONAL SECURITY SITE.

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 TWITTER #NWSVEGAS.

&&

LAT...LON 3692 11600 3692 11577 3674 11577 3674 11600

$$

MORGAN
2 follow-up statements
240 
WGUS75 KVEF 112328
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
428 PM PDT SUN SEP 11 2011

NVC003-017-023-120030-
/O.CON.KVEF.FF.W.0081.000000T0000Z-110912T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-NYE NV-LINCOLN NV-
428 PM PDT SUN SEP 11 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM PDT FOR
EXTREME SOUTHWESTERN LINCOLN...SOUTH CENTRAL NYE AND NORTHWESTERN
CLARK COUNTIES...

AT 423 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A THUNDERSTORM PRODUCING VERY HEAVY RAIN.  THIS STORM WAS
LOCATED OVER EXTREME NORTHWESTERN CLARK COUNTY...OR 13 MILES
NORTHEAST OF MERCURY. THE THUNDERSTORM WITH EXCESSIVE RAIN WAS NEARLY
STATIONARY. THE HEAVY RAIN FROM THIS THUNDERSTORM WILL DRAIN INTO A 
DRY LAKE BED ON THE SOUTHERN PART OF THE NEVADA NATIONAL SECURITY 
SITE...A FEW MILES NORTH OF MERCURY. ANYONE WORKING IN OR NEAR THIS 
DRY LAKE BED SHOULD MOVE TO HIGHER GROUND.

LOCATIONS IMPACTED INCLUDE...
MAINLY RURAL AREAS OF EXTREME EASTERN NYE COUNTY.

LAT...LON 3692 11600 3692 11577 3674 11577 3674 11600

$$

MORGAN
993 
WGUS75 KVEF 120030
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
530 PM PDT SUN SEP 11 2011

NVC003-017-120038-
/O.CAN.KVEF.FF.W.0081.000000T0000Z-110912T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-LINCOLN NV-
530 PM PDT SUN SEP 11 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EXTREME
SOUTHWESTERN LINCOLN AND NORTHWESTERN CLARK COUNTIES...

THE HEAVY RAIN HAS ENDED AND THE IMMEDIATE THREAT OF ADDITIONAL 
FLASH FLOODING HAS ENDED...BUT RUNOFF MAY CONTINUE TO CAUSE MINOR 
FLOODING AND RAPIDLY RUNNING WASHES THROUGH 800 PM.

LAT...LON 3689 11600 3691 11590 3674 11590 3674 11600

$$

NVC023-120030-
/O.CON.KVEF.FF.W.0081.000000T0000Z-110912T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NYE NV-
530 PM PDT SUN SEP 11 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM PDT FOR SOUTH
CENTRAL NYE COUNTY...

AT 524 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A THUNDERSTORM PRODUCING VERY HEAVY RAIN.  THIS STORM WAS
LOCATED OVER SOUTH CENTRAL NYE COUNTY...OR 11 MILES NORTH OF MERCURY.
THE THUNDERSTORM WITH EXCESSIVE RAIN WAS NEARLY STATIONARY. RADAR 
ESTIMATES OVER THE PAST 3 HOURS HAVE BEEN IN EXCESS OF THREE INCHES 
OVER A LARGE AREA AND ALL OF THE RUNOFF HAS BEEN INTO SOUTHERN NYE 
COUNTY. 

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 TWITTER #NWSVEGAS.

&&

LAT...LON 3689 11600 3691 11590 3674 11590 3674 11600

$$

SC

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 2:06 PM PDTSevere Thunderstorm WarningVEFClark24 min
Sep 11, 2:52 PM PDTSevere Thunderstorm WarningVEFClark23 min
Sep 11, 3:03 PM PDTSevere Thunderstorm WarningVEFClark27 min
Sep 11, 3:13 PM PDTSevere Thunderstorm WarningVEFClark47 min
Sep 11, 3:26 PM PDTSevere Thunderstorm WarningVEFClark, Lincoln, Nye24 min
Sep 11, 3:52 PM PDTSevere Thunderstorm WarningVEFClark38 min
Sep 11, 4:25 PM PDTSevere Thunderstorm WarningVEFClark, Lincoln35 min
Sep 11, 4:30 PM PDTSevere Thunderstorm WarningVEFLincoln35 min
Sep 11, 4:37 PM PDTAreal Flood AdvisoryVEFNye47 min
Sep 11, 4:54 PM PDTSevere Thunderstorm WarningVEFClark, Lincoln36 min

Nearby

Flash Flood Warnings in Nevada, 2011Every flash flood warning in 2011

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.