Alert archive / Nevada / Flash Flood Warnings in 2018

Flash Flood Warning 151, NWS Las Vegas, NV

October 4, 2018Clark County, Nevada; San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Oct 4, 2018, 12:11 AM PDT for Clark County, Nevada; San Bernardino County, California. 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
Oct 4, 2018, 12:11 AM PDT (07:11 UTC)
Expired
Oct 4, 2018, 3:15 AM PDT
In force
3 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

Counties San Bernardino County, CA, Clark County, NV

The radar

The Las Vegas radar (KESX), 56 km from the middle of the area, began a volume at 07:16 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 00:00Z, 7.2 hours before the alert went out and 132 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 00:00Z on 2018-10-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 65 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2018-10-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 square meters per square second.1939587897117Sfc1 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
65 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
2880 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
-2 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.

986 
WGUS55 KVEF 040711
FFWVEF
CAC071-NVC003-041015-
/O.NEW.KVEF.FF.W.0151.181004T0711Z-181004T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
1211 AM PDT THU OCT 4 2018

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  Northeastern San Bernardino County in southern California...
  South central Clark County in southern Nevada...

* Until 315 AM PDT.

* At 1209 AM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain across eastern areas of the Mojave National Preserve. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Searchlight, Mitchell Caverns, Nipton Road Mile Marker 3, Black
  Canyon Equestrian Campground, Cal-Nev-Ari and Hole In The Wall
  Campground.

LAT...LON 3538 11482 3497 11501 3495 11515 3482 11524
      3482 11567 3539 11513 3553 11530 3558 11526
      3551 11484

$$

Boothe
1 follow-up statement
390 
WGUS75 KVEF 041007
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
307 AM PDT THU OCT 4 2018

CAC071-NVC003-041016-
/O.EXP.KVEF.FF.W.0151.000000T0000Z-181004T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-Clark NV-
307 AM PDT THU OCT 4 2018

...THE FLASH FLOOD WARNING FOR NORTHEASTERN SAN BERNARDINO AND SOUTH
CENTRAL CLARK COUNTIES WILL EXPIRE AT 315 AM 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 3538 11482 3497 11501 3495 11515 3482 11524
      3482 11567 3539 11513 3553 11530 3558 11526
      3551 11484

$$

JS

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 3, 5:26 PM PDTAreal Flood AdvisoryVEFLincoln3 hr
Oct 3, 7:22 PM PDTAreal Flood AdvisoryVEFLincoln5 hr
Oct 3, 9:30 PM PDTFlash Flood WarningVEFClark5 hr
Oct 3, 10:20 PM PDTAreal Flood AdvisoryVEFNye79 min
Oct 4, 1:53 AM PDTFlash Flood WarningVEFClark2 hr
Oct 3, 5:46 PM PDTFlash Flood WarningVEFInyo, San Bernardino119 min
Oct 3, 6:06 PM PDTAreal Flood AdvisoryVEFSan Bernardino3 hr
Oct 3, 6:18 PM PDTSevere Thunderstorm WarningVEFInyo, San Bernardino42 min
Oct 3, 7:54 PM PDTAreal Flood AdvisoryVEFSan Bernardino2 hr
Oct 3, 8:18 PM PDTSevere Thunderstorm WarningVEFSan Bernardino24 min
Oct 3, 8:55 PM PDTFlash Flood WarningVEFSan Bernardino5 hr
Oct 3, 9:54 PM PDTFlash Flood WarningVEFSan Bernardino2 hr
Oct 3, 10:16 PM PDTAreal Flood AdvisoryVEFSan Bernardino2 hr
Oct 3, 10:47 PM PDTFlash Flood WarningVEFSan Bernardino3 hr

Nearby

Flash Flood Warnings in Nevada, 2018Flash Flood Warnings in California, 2018Every flash flood warning in 2018

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.