Alert archive / California / Flash Flood Warnings in 2016

Flash Flood Warning 70, NWS Las Vegas, NV

August 3, 2016San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 3, 2016, 8:40 PM PDT for San Bernardino County, California. It was in force for 6 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 3, 2016, 8:40 PM PDT (03:40 UTC)
Expired
Aug 4, 2016, 2:30 AM PDT
In force
6 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County San Bernardino County, CA

The radar

The Las Vegas radar (KESX), 143 km from the middle of the area, began a volume at 03:40 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

Yuma Prvg Ground, AZ (K1Y7), launched 00:00Z, 3.7 hours before the alert went out and 218 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, Yuma Prvg Ground, AZ at 00:00Z on 2016-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 172 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Yuma Prvg Ground, AZ at 00:00Z on 2016-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -48 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
172 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
2778 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-48 m²/s²
0-3 km storm-relative helicity
-47 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

152 
WGUS55 KVEF 040340
FFWVEF
CAC071-040930-
/O.NEW.KVEF.FF.W.0070.160804T0340Z-160804T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
840 PM PDT WED AUG 3 2016

THE NATIONAL WEATHER SERVICE IN LAS VEGAS  HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN SAN BERNARDINO COUNTY IN SOUTHERN CALIFORNIA...

* UNTIL 230 AM PDT

* NUMEROUS THUNDERSTORMS HAVE BEEN PRODUCING HEAVY RAIN WEST OF
  HIGHWAY 95 OVER CHEMEHUEVI WASH. RUNOFF FROM THIS HEAVY RAIN WILL
  FLOW DOWN THE WASH AND ACROSS HIGHWAY 95 ABOUT HALF WAY BETWEEN
  NEEDLES AND VIDAL JUNCTION. FLOOD WATERS WILL EVENTUALLY WORK DOWN
  CHEMEHUEVI WASH TO THE HAVASU LAKE AREA. 

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  HIGHWAY 95 AT MILE MARKER 29.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3436 11485 3462 11483 3450 11438 3447 11438
      3446 11439 3445 11438 3445 11434 3444 11433
      3443 11436

$$

JH
2 follow-up statements
865 
WGUS75 KVEF 040645
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1145 PM PDT WED AUG 3 2016

CAC071-040930-
/O.CON.KVEF.FF.W.0070.000000T0000Z-160804T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1145 PM PDT WED AUG 3 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 230 AM PDT FOR
SOUTHEASTERN SAN BERNARDINO COUNTY...

AT 1142 PM PDT...RAIN HAD ENDED ACROSS SOUTHEAST SAN BERNARDINO
COUNTY. HOWEVER...RUNOFF HEADING DOWN CHEMEHUEVI WASH COULD STILL
FLOOD HIGHWAY 95 AND POINTS DOWN THE WASH TO THE EAST.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
HIGHWAY 95 AT MILE MARKER 29.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3436 11485 3462 11483 3450 11438 3447 11438
      3446 11439 3445 11438 3445 11434 3444 11433
      3443 11436

$$

JH
069 
WGUS75 KVEF 040814
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
114 AM PDT THU AUG 4 2016

CAC071-040823-
/O.CAN.KVEF.FF.W.0070.000000T0000Z-160804T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
114 AM PDT THU AUG 4 2016

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN SAN BERNARDINO COUNTY IS
CANCELLED...

THERE WERE NO REPORTS OF FLOODING ON HIGHWAY 95 FROM EARLIER HEAVY
RAIN IN THE CHEMEHUEVI WASH, SO THE FLASH FLOOD WARNING HAS BEEN
CANCELLED.

LAT...LON 3436 11485 3462 11483 3450 11438 3447 11438
      3446 11439 3445 11438 3445 11434 3444 11433
      3443 11436

$$

MORGAN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 6:20 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 4, 12:37 AM PDTFlash Flood WarningVEFSan Bernardino113 min
Aug 4, 2:24 AM PDTFlash Flood WarningVEFSan Bernardino2 hr
Aug 4, 1:49 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 4, 3:25 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 4, 4:39 PM PDTAreal Flood AdvisoryVEFSan Bernardino5 hr
Aug 4, 4:42 PM PDTAreal Flood AdvisoryVEFSan Bernardino3 hr

Nearby

Flash Flood Warnings in California, 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.