Alert archive / California / Flash Flood Warnings in 2004

Flash Flood Warning 4, NWS Las Vegas, NV

August 12, 2004San Bernardino County, California; Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 12, 2004, 9:53 PM PDT for San Bernardino County, California; Clark County, Nevada. It was in force for 29 days. 1 report 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
Aug 12, 2004, 9:53 PM PDT (04:53 UTC)
Expired
Sep 10, 2004, 4:30 PM PDT
In force
29 days
Issued by
NWS Las Vegas, NV
Area
Counties, with a storm outline in the text

Counties San Bernardino County, CA, Clark County, NV

The radar

The Las Vegas radar (KESX), 64 km from the middle of the area, began a volume at 04:53 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 9, 7:21 PM PDTFLASH FLOOD9 W Nipton, CACALIFORNIA HIGHWAY PATROL REPORTED NIPTON RD ABOUT 500 FEET FROM INTERSTATE 15. ROADWAY IS COMPLETELY WASHED OUT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Mercury/Desert R, NV (KDRA), launched 00:00Z, 4.9 hours before the alert went out and 129 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 00:00Z on 2004-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2004-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
4380 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
40 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.

000 
WGUS55 KVEF 130452
FFWVEF
NVC003-130645-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
953 PM PDT THU AUG 12 2004

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 1145 PM PDT

* AT 945 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM NEAR CALLVILLE BAY...MOVING
  SOUTH AT 5 MPH.

* THE STORM PRODUCING FLASH FLOODING WILL OTHERWISE REMAIN OVER   
  THE BOULDER BASIN AREA OF LAKE MEAD.

ADDITIONAL RAINFALL AMOUNTS OF ONE INCH ARE POSSIBLE OVER THE AREA 
NEAR NORTHSHORE ROAD BETWEEN LAS VEGAS BAY AND CALLVILLE BAY. GYPSUM 
AND GOVERNMENT WASHES WILL LIKELY BEGIN TO FILL WITH SIGNIFICANT 
RUNOFF AND COULD AFFECT TRAVEL ALONG NORTHSHORE ROAD.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE 
DANGERS OF FLOODING. DO NOT DRIVE OR WALK ACROSS AREAS WHERE WATER 
COVERS THE ROAD.

LAT...LON 3623 11457 3626 11474 3611 11479 3616 11457

$$

ADAIR
1 follow-up statement
000 
WGUS55 KVEF 102135
FFWVEF
CAC071-102330-
/X.NEW.KVEF.FF.W.0004.040910T2133Z-040910T2330Z/
/0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
233 PM PDT FRI SEP 10 2004

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL SAN BERNARDINO COUNTY IN SOUTHEAST CALIFORNIA

* UNTIL 430 PM PDT

* AT 224 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM A THUNDERSTORM OVER ALONG I-15 NEAR MOUNTAIN   
  PASS.

* THE STORM PRODUCING FLASH FLOODING WILL CONTINUE TO IMPACT I-15    
  NEAR MOUNTAIN PASS BETWEEN MILE MARKER 166 AND 175.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

FLOODING IS OCCURRING OR IS IMMINENT. MOST FLOOD RELATED DEATHS OCCUR
IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED BRIDGES...
DIPS...OR LOW WATER CROSSINGS. NEVER TRY TO CROSS A FLOWING STREAM...
EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER
GROUND.

LAT...LON 3552 11573 3537 11560 3551 11530 3566 11546

$$
CZYZYK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 13, 11:08 AM PDTSevere Thunderstorm WarningVEFSan Bernardino37 min
Aug 13, 11:32 AM PDTFlash Flood WarningVEFSan Bernardino28 days
Aug 13, 12:14 PM PDTFlash Flood WarningVEFSan Bernardino2 hr
Aug 13, 12:42 PM PDTSevere Thunderstorm WarningVEFSan Bernardino48 min
Aug 13, 12:57 PM PDTSevere Thunderstorm WarningVEFSan Bernardino48 min
Aug 13, 1:36 PM PDTFlash Flood WarningVEFSan Bernardino28 days

Nearby

Flash Flood Warnings in California, 2004Flash Flood Warnings in Nevada, 2004Every flash flood warning in 2004

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.