Alert archive / Nevada / Flash Flood Warnings in 2016

Flash Flood Warning 90, NWS Las Vegas, NV

August 18, 2016Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 18, 2016, 4:56 PM PDT for Clark County, Nevada. It was in force for 3 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, 2016, 4:56 PM PDT (23:56 UTC)
Expired
Aug 18, 2016, 8:00 PM PDT
In force
3 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), 100 km from the middle of the area, began a volume at 23:57 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, 11.9 hours before the alert went out and 78 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 2016-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 18 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 2016-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
18 J/kg
Mixed-layer CIN
-295 J/kg
Mixed-layer LCL
3236 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

770 
WGUS55 KVEF 182356
FFWVEF
NVC003-190300-
/O.NEW.KVEF.FF.W.0090.160818T2356Z-160819T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
456 PM PDT THU AUG 18 2016

THE NATIONAL WEATHER SERVICE IN LAS VEGAS  HAS ISSUED A

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

* UNTIL 800 PM PDT

* AT 455 PM PDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. FLASH FLOODING IS EXPECTED TO
  BEGIN SHORTLY. A RAIN GAUGE NEAR MOAPA HAS REPORTED NEARLY AN INCH
  OF RAIN IN ONE HOUR. 

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  MOAPA TOWN...OVERTON...MOAPA VALLEY...
  LOGANDALE AND SR 168 MILE MARKER 21.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO CROSS FLOODED
ROADS. FIND AN ALTERNATE ROUTE.

&&

LAT...LON 3643 11494 3679 11496 3681 11437 3650 11432

$$

ASG
3 follow-up statements
919 
WGUS55 KVEF 182358 CCA
FFWVEF
NVC003-190300-
/O.COR.KVEF.FF.W.0090.160818T2356Z-160819T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
458 PM PDT THU AUG 18 2016

THE NATIONAL WEATHER SERVICE IN LAS VEGAS  HAS ISSUED A

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

* UNTIL 800 PM PDT

* AT 457 PM PDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. FLASH FLOODING IS EXPECTED TO
  BEGIN SHORTLY. A RAIN GAUGE NEAR MOAPA HAS REPORTED NEARLY AN INCH
  OF RAIN IN FIFTEEN MINUTES.  

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  MOAPA TOWN...OVERTON...MOAPA VALLEY...
  LOGANDALE AND SR 168 MILE MARKER 21.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO CROSS FLOODED
ROADS. FIND AN ALTERNATE ROUTE.

&&

LAT...LON 3643 11494 3679 11496 3681 11437 3650 11432

$$

ASG
553 
WGUS75 KVEF 190134
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
634 PM PDT THU AUG 18 2016

NVC003-190300-
/O.CON.KVEF.FF.W.0090.000000T0000Z-160819T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
634 PM PDT THU AUG 18 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM PDT FOR
NORTHEASTERN CLARK COUNTY...

AT 631 PM PDT...DOPPLER RADAR INDICATED RAIN HAS LIGHTENED UP ACROSS
THE AREA, BUT ADDITIONAL THUNDERSTORMS WITH HEAVY RAIN ARE LIKELY TO
MOVE INTO THE AREA. RAIN GAUGES IN THE AREA HAVE REPORTED NEARLY TWO
INCHES OF RAIN IN THE PAST TWO HOURS.  

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
MOAPA TOWN...OVERTON...MOAPA VALLEY...
LOGANDALE AND SR 168 MILE MARKER 21.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 3643 11494 3679 11496 3681 11437 3650 11432

$$

ASG
862 
WGUS75 KVEF 190254
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
754 PM PDT THU AUG 18 2016

NVC003-190304-
/O.EXP.KVEF.FF.W.0090.000000T0000Z-160819T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
754 PM PDT THU AUG 18 2016

...THE FLASH FLOOD WARNING FOR NORTHEASTERN CLARK COUNTY WILL EXPIRE
AT 800 PM PDT...

THE HEAVY RAIN HAS ENDED. FLOODING IS NO LONGER EXPECTED TO POSE A
THREAT. PLEASE CONTINUE TO HEED ANY REMAINING ROAD CLOSURES.

LAT...LON 3643 11494 3679 11496 3681 11437 3650 11432

$$

ASG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 2:30 PM PDTFlash Flood WarningVEFClark3 hr
Aug 18, 3:08 PM PDTSevere Thunderstorm WarningVEFClark37 min
Aug 18, 4:22 PM PDTSevere Thunderstorm WarningVEFClark38 min

Nearby

Flash Flood Warnings in Nevada, 2016Every flash flood warning in 2016

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.