Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 204, NWS Las Vegas, NV

September 11, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Sep 11, 2012, 2:18 PM PDT for Clark County, Nevada. It was in force for 4 hr. 8 reports 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
Sep 11, 2012, 2:18 PM PDT (21:18 UTC)
Expired
Sep 11, 2012, 6:15 PM PDT
In force
4 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), 99 km from the middle of the area, began a volume at 21:18 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
Sep 11, 2:45 PM PDTFLASH FLOODValley Of Fire (Slcn2), NVVALLEY OF FIRE VISTORS CENTER REPORTS 2 FEET OF WATER ACROSS A SECTION OF WHITE DOME ROAD. IN PROCESS OF EVACUATING AND CLOSING PARK.
Sep 11, 2:50 PM PDTFLASH FLOODOverton, NVREPORT FROM THE NHP THAT STATE ROUTE 169 IN OVERTON IS CLOSED NEAR THE OVERTON WASH.
Sep 11, 2:55 PM PDTFLASH FLOOD5 Sse Logandale, NVSPOTTER REPORTS THAT 1.5 FEET OF WATER OVER WARM SPRING LOOP ROAD AND ALSO OVER STATE ROUTE 168 IN MOAPA.
Sep 11, 2:59 PM PDTFLASH FLOOD2 Sse Logandale, NVSPOTTER REPORTED MULTIPLE ROAD CLOSURES IN LOGANDALE. GUBLER ROAD AND HEYER IS CLOSED.
Sep 11, 3:04 PM PDTFLASH FLOOD10 Sw Moapa, NVNHP REPORTS THAT INTERSTATE 15 IS CLOSED AT MILE MARKER 75. THIS IS WHERE THE CALIFORNIA WASH CROSSES I-15.
Sep 11, 3:04 PM PDTFLASH FLOOD4 Wnw California Wash (, NVNHP REPORTS THAT INTERSTATE 15 IS CLOSED AT MILE MARKER 75. THIS IS WHERE THE CALIFORNIA WASH CROSSES I-15.
Sep 11, 5:17 PM PDTFLASH FLOOD1 Sse Moapa, NVSWIFT WATER RESCUE WHERE THE CALIFORNIA WASH CROSSES HIDDEN VALLEY ROAD IN MOAPA. WATER IS FLOWING OVER THE CAB OF THE PICKUP TRUCK.
Sep 11, 5:17 PM PDTFLASH FLOOD5 Sse Logandale, NVSWIFT WATER RESCUE WHERE THE CALIFORNIA WASH CROSSES HIDDEN VALLEY ROAD IN MOAPA. WATER IS FLOWING OVER THE CAB OF THE PICKUP TRUCK.

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 12:00Z, 9.3 hours before the alert went out and 89 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 2012-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 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 2012-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
2 J/kg
Mixed-layer CIN
-171 J/kg
Mixed-layer LCL
1725 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
37 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.

362 
WGUS55 KVEF 112118
FFWVEF
NVC003-120115-
/O.NEW.KVEF.FF.W.0204.120911T2118Z-120912T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
218 PM PDT TUE SEP 11 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 615 PM PDT.

* AT 214 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM A CLUSTER OF THUNDERSTORMS FROM VALLEY OF
  FIRE TO MOAPA AND OVERTON.  THE THUNDERSTORMS WERE MOVING EAST
  AROUND 10 MPH AND WILL PRODUCE OVER ONE INCH OF RAINFALL IN LESS
  THAN AN HOUR. HIGH WATER FLOWS ARE ALSO EXPECTED IN CALIFORNIA 
  WASH... THE MUDDY RIVER AND MEADOW VALLEY WASH.

* LOCATIONS IMPACTED INCLUDE...
  OVERTON...VALLEY OF FIRE STATE PARK...VALLEY OF FIRE...LOGANDALE
  AND OVERTON BEACH.

THIS INCLUDES INTERSTATE 15 BETWEEN MILE MARKERS 69 AND 93.

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 3675 11460 3647 11434 3636 11443 3644 11488

$$

JA
3 follow-up statements
071 
WGUS75 KVEF 112228
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
328 PM PDT TUE SEP 11 2012

NVC003-120115-
/O.CON.KVEF.FF.W.0204.000000T0000Z-120912T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
328 PM PDT TUE SEP 11 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM PDT FOR
CENTRAL CLARK COUNTY...

LOCAL LAW ENFORCEMENT OFFICIALS REPORTED THAT STATE ROUTE 168 IN 
MOAPA AND STATE ROUTE 169 IN OVERTON WERE CLOSED AROUND 250 PM DUE 
TO FLASH FLOODING. FLOODING WAS ALSO IMPACTING ROADS IN VALLEY OF 
FIRE AND A STATE PARK OFFICIAL SAID THE PARK WAS BEING EVACUATED 
BETWEEN 230 PM AND 3 PM. THUNDERSTORMS THAT PRODUCED HEAVY RAIN OVER 
THIS AREA HAVE DISSIPATED AND MOVED TO THE EAST BUT LIGHT TO 
MODERATE RAIN SHOWERS WILL PERSIST THROUGH 430 PM.

FLOODING OF WASHES AND ROADS IN THE AREA WILL CONTINUE THROUGH THE 
LATE AFTERNOON AS RUNOFF FROM THE PREVIOUS HEAVY RAINFALL MAKES ITS 
WAY DOWN DRAINAGE CHANNELS.ALSO...THE CALIFORNIA WASH WHICH 
PARALLELS I-15 AND FLOWS TOWARD MOAPA AND EVENTUALLY LOGANDALE AND 
OVERTON WILL BE CARRYING HIGH WATER.

LOCATIONS IMPACTED INCLUDE...
OVERTON...MOAPA AND LOGANDALE.

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 3675 11460 3647 11434 3636 11443 3644 11488

$$

JA
947 
WGUS75 KVEF 112353
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
453 PM PDT TUE SEP 11 2012

NVC003-120115-
/O.CON.KVEF.FF.W.0204.000000T0000Z-120912T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
453 PM PDT TUE SEP 11 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM PDT FOR 
NORTHEAST CLARK COUNTY...

LOCAL LAW ENFORCEMENT OFFICIALS REPORTED WATER FLOWING BANK FULL IN 
THE CALIFORNIA WASH WHICH FLOWS ACROSS STATE ROUTES 78 AND 168 NEAR 
MOAPA. WATER FROM THE WASH CLOSED THE SOUTHBOUND LANE OF INTERSTATE 
15 AROUND 3 PM. THIS HIGH WATER WILL FLOW INTO THE MUDDY RIVER THEN 
MAKE ITS WAY DOWN THROUGH LOGANDALE AND OVERTON THIS EVENING. NO 
ADDITIONAL SIGNIFICANT RAIN IS EXPECTED BUT PEOPLE IN THE MOAPA 
VALLEY NEED TO BE AWARE OF HIGH FLOWS IN THE MUDDY RIVER WHICH MAY 
IMPACT ROADS LATER THIS EVENING.

THIS INCLUDES INTERSTATE 15 NEAR MILE MARKER 75.

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 3675 11460 3647 11434 3636 11443 3644 11488

$$

JA
707 
WGUS75 KVEF 120114
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
614 PM PDT TUE SEP 11 2012

NVC003-120122-
/O.EXP.KVEF.FF.W.0204.000000T0000Z-120912T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
614 PM PDT TUE SEP 11 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 615 PM PDT FOR CENTRAL
CLARK COUNTY...

HEAVY RAIN HAS ENDED ACROSS NORTHEAST CLARK COUNTY BUT HIGH FLOWS IN 
THE CALIFORNIA WASH WILL MOVE DOWN THE MUDDY RIVER THROUGH LOGANDALE 
AND OVERTON LATE THIS EVENING AND LIKELY THROUGH EARLY WEDNESDAY 
MORNING. THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE ON 
SCHEDULE BUT A FLOOD WARNING IS IN EFFECT FOR THE MUDDY RIVER 
THROUGH 4 AM WEDNESDAY.

LAT...LON 3675 11460 3647 11434 3636 11443 3644 11488

$$

JA

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 3:24 AM PDTFlash Flood WarningVEFClark111 min
Sep 11, 4:52 AM PDTFlash Flood WarningVEFNye113 min
Sep 11, 8:28 AM PDTAreal Flood AdvisoryVEFLincoln3 hr
Sep 11, 11:33 AM PDTAreal Flood AdvisoryVEFClark3 hr
Sep 11, 12:32 PM PDTFlash Flood WarningVEFClark88 min
Sep 11, 1:44 PM PDTAreal Flood AdvisoryVEFClark27 min
Sep 11, 1:51 PM PDTFlash Flood WarningVEFClark114 min
Sep 11, 2:08 PM PDTFlash Flood WarningVEFClark93 min
Sep 11, 2:16 PM PDTSevere Thunderstorm WarningVEFClark44 min
Sep 11, 3:39 PM PDTFlash Flood WarningVEFClark2 hr
Sep 11, 4:02 PM PDTFlash Flood WarningVEFClark118 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.