Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 42, NWS Las Vegas, NV

July 15, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jul 15, 2012, 1:12 PM PDT for Clark 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
Jul 15, 2012, 1:12 PM PDT (20:12 UTC)
Expired
Jul 15, 2012, 3:15 PM PDT
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Clark County, NV

The radar

The Las Vegas radar (KESX), 93 km from the middle of the area, began a volume at 20:15 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, 8.2 hours before the alert went out and 12 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 2012-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 335 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 2012-07-15The 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
335 J/kg
Mixed-layer CIN
-212 J/kg
Mixed-layer LCL
1353 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
8 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.

412 
WGUS55 KVEF 152012
FFWVEF
NVC003-152215-
/O.NEW.KVEF.FF.W.0042.120715T2012Z-120715T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
112 PM PDT SUN JUL 15 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 315 PM PDT.

* AT 110 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR HILLTOP CAMPGROUND...OR
  NEAR MT. CHARLESTON. THE STORM PRODUCING VERY HEAVY 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.

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 3642 11571 3642 11549 3611 11549 3611 11572

$$

STACHELSKI
2 follow-up statements
168 
WGUS75 KVEF 152103
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
203 PM PDT SUN JUL 15 2012

NVC003-152215-
/O.CON.KVEF.FF.W.0042.000000T0000Z-120715T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
203 PM PDT SUN JUL 15 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 PM PDT FOR WEST
CENTRAL CLARK COUNTY...

AT 155 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE THUNDERSTORMS MOVING SLOWLY NORTH AROUND 5 MPH OVER MT 
CHARLESTON. HEAVY RAIN WAS REPORTED EARLIER ON MT CHARLESTON WITH 
RUNOFF CAUSING DEBRIS INCLUDING LARGE ROCKS TO WASH ONTO ROADS. 
ALTHOUGH RAINFALL IS NOT AS HEAVY AS ABOUT AN HOUR AGO...ADDITIONAL 
RAINFALL AND RUNOFF FROM EARLIER ACTIVITY WILL STILL RESULT IN 
FLOODING AS WELL AS THE POTENTIAL FOR DEBRIS TO WASH ONTO ROADS. 

LOCATIONS IMPACTED INCLUDE...
MT CHARLESTON.

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 3642 11571 3642 11549 3611 11549 3611 11572

$$

STACHELSKI
767 
WGUS75 KVEF 152214
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
314 PM PDT SUN JUL 15 2012

NVC003-152223-
/O.EXP.KVEF.FF.W.0042.000000T0000Z-120715T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
314 PM PDT SUN JUL 15 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 315 PM PDT FOR WEST CENTRAL
CLARK COUNTY...

HEAVY RAIN HAS ENDED OVER MT. CHARLESTON AND RADAR SHOWED ANY RAIN 
FALLING ACROSS MT CHARLESTON WAS PRESENTLY LIGHT IN INTENSITY. BE 
CAREFUL IF TRAVELING IN THIS AREA AS ROADS WILL STILL BE SLICK FROM 
THE HEAVIER RAIN THAT FELL EARLIER.

LAT...LON 3642 11571 3642 11549 3611 11549 3611 11572

$$

STACHELSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 6:02 PM PDTAreal Flood AdvisoryVEFClark116 min
Jul 14, 8:41 PM PDTAreal Flood AdvisoryVEFClark16 min
Jul 14, 8:56 PM PDTFlash Flood WarningVEFClark109 min
Jul 15, 10:14 AM PDTFlash Flood WatchVEFClark, Lincoln, Nye11 hr
Jul 15, 10:30 AM PDTFlash Flood WarningVEFLincoln4 hr
Jul 15, 1:24 PM PDTFlash Flood WarningVEFNye4 hr
Jul 15, 1:58 PM PDTFlash Flood WarningVEFLincoln82 min
Jul 15, 2:16 PM PDTSevere Thunderstorm WarningVEFClark44 min
Jul 15, 2:41 PM PDTAreal Flood AdvisoryVEFClark3 hr
Jul 15, 3:01 PM PDTFlash Flood WarningVEFLincoln6 hr
Jul 15, 4:40 PM PDTFlash Flood WarningVEFClark65 min
Jul 15, 4:58 PM PDTFlash Flood WarningVEFClark92 min

Nearby

Flash Flood Warnings in Nevada, 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.