Alert archive / Nevada / Flash Flood Warnings in 1997

Flash Flood Warning 30, NWS Las Vegas, NV

August 10, 1997Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 10, 1997, 2:44 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 counties it named.

The facts

Issued
Aug 10, 1997, 2:44 PM PDT (21:44 UTC)
Expired
Aug 10, 1997, 4:45 PM PDT
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Whole counties

County Clark County, NV

The radar

The Las Vegas radar (KESX), 58 km from the middle of the area, began a volume at 21:48 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

Mercury/Desert R, NV (KDRA), launched 12:00Z, 9.7 hours before the alert went out and 99 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, Mercury/Desert R, NV at 12:00Z on 1997-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 714 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Mercury/Desert R, NV at 12:00Z on 1997-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 square meters per square second.193958Sfc1 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
714 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
2121 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KLAS 102149 COR
FFWLAS
NVC003-102345-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING...CORRECTION HEADER
NATIONAL WEATHER SERVICE LAS VEGAS NV
244 PM PDT SUN AUG 10 1997

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS EXTENDED THE
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
EFFECTIVE UNTIL  445 PM PDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......

IN SOUTH NEVADA

   ...EASTERN CLARK COUNTY

AT 240 PM...LAS VEGAS DOPPLER RADAR CONTINUED TO SHOW A LINE OF
SEVERE THUNDERSTORMS OVER EASTERN CLARK COUNTY ROUGHLY ALONG AND
SOUTHEAST OF INTERSTATE HIGHWAY 15.  THE LINE OF THUNDERSTORMS HAS
BEEN NEARLY STATIONARY WITH INDIVIDUAL CELLS MOVING TO THE NORTHEAST
AT 15 TO 20 MPH.

THIS IS A VERY DANGEROUS SITUATION WITH SEVERE FLASH FLOODING
OCCURRING IN HENDERSON...BOULDER CITY AS WELL AS MUCH OF THE LAKE
MEAD RECREATION AREA WITH MANY ROADS CLOSED AT THE PRESENT TIME.
DO NOT ATTEMPT TO DRIVE IN THESE AREAS.

THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH YOU SHOULD
PREPARE FOR DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...AND
DEADLY LIGHTNING.  PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT STAY AWAY FROM WINDOWS.

KOSIER

&

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Las Vegas, NV wrote its last area forecast discussion before this flash flood warning went out at Aug 10, 2:10 PM PDT, 34 minutes earlier.

Area forecast discussion, Aug 10, 2:10 PM PDT, 34 minutes before
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
210 PM PDT SUN AUG 10 1997

NO TIME FOR DISCUSSION WITH LOTS OF SEVERE WEATHER AND FLASH
FLOODING OCCURRING ATTM OVER EXTREME SRN NV/NW AZ.  WILL CONTINUE
WITH PREVIOUS TREND OF IMPROVING CONDS NEXT FEW DAYS.
LAS 4000.  KOSIER

SRN NV...NONE
ERN CA...NONE
NW AZ ...NONE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 5:02 PM PDTSevere Thunderstorm WarningVEFClark58 min
Aug 9, 5:56 PM PDTSevere Thunderstorm WarningVEFClark34 min
Aug 9, 9:29 PM PDTFlash Flood WarningVEFLincoln2 hr
Aug 10, 12:11 PM PDTSevere Thunderstorm WarningVEFClark64 min
Aug 10, 12:58 PM PDTFlash Flood WarningVEFClark2 hr
Aug 10, 12:58 PM PDTSevere Thunderstorm WarningVEFClark2 hr
Aug 10, 1:49 PM PDTFlash Flood WarningVEFLincoln56 min
Aug 10, 1:49 PM PDTSevere Thunderstorm WarningVEFLincoln56 min
Aug 10, 2:00 PM PDTFlash Flood WarningVEFLincoln2 hr
Aug 10, 2:20 PM PDTFlash Flood WarningVEFLincoln100 min
Aug 10, 2:20 PM PDTSevere Thunderstorm WarningVEFLincoln100 min
Aug 10, 2:44 PM PDTSevere Thunderstorm WarningVEFClark2 hr
Aug 10, 3:52 PM PDTFlash Flood WarningVEFLincoln3 hr
Aug 10, 3:52 PM PDTSevere Thunderstorm WarningVEFLincoln3 hr
Aug 10, 4:43 PM PDTFlash Flood WarningVEFClark2 hr
Aug 10, 4:43 PM PDTSevere Thunderstorm WarningVEFClark2 hr

Nearby

Flash Flood Warnings in Nevada, 1997Every flash flood warning in 1997

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.