Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 80, NWS Las Vegas, NV

August 4, 2017San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 4, 2017, 5:41 PM PDT for 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
Aug 4, 2017, 5:41 PM PDT (00:41 UTC)
Expired
Aug 4, 2017, 8:45 PM PDT
In force
3 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), 96 km from the middle of the area, began a volume at 00:42 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, 0.7 hours before the alert went out and 90 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 2017-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 229 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 00:00Z on 2017-08-05The 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
229 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
1976 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

272 
WGUS55 KVEF 050041
FFWVEF
CAC071-050345-
/O.NEW.KVEF.FF.W.0080.170805T0041Z-170805T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
541 PM PDT FRI AUG 4 2017

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  North central San Bernardino County in southern California...

* Until 845 PM PDT

* At 541 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain northeast San Bernardino County. Flash flooding is 
  expected to begin shortly.

* Some locations that will experience flooding include...
  Baker, Mountain Pass, Nipton And Ivanpah Roads, Nipton, Sr 127 Near
  Dumont Dunes, Dumont Dunes and Tecopa.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3580 11658 3579 11574 3581 11573 3581 11565
      3541 11515 3508 11626

$$

ASG
1 follow-up statement
569 
WGUS75 KVEF 050216
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
716 PM PDT FRI AUG 4 2017

CAC071-050225-
/O.CAN.KVEF.FF.W.0080.000000T0000Z-170805T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
716 PM PDT FRI AUG 4 2017

...THE FLASH FLOOD WARNING FOR NORTH CENTRAL SAN BERNARDINO COUNTY IS
CANCELLED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3580 11658 3579 11574 3581 11573 3581 11565
      3541 11515 3508 11626

$$

ASG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 10:45 PM PDTAreal Flood AdvisoryVEFInyo3 hr
Aug 5, 4:33 PM PDTAreal Flood AdvisoryVEFInyo3 hr

Nearby

Flash Flood Warnings in California, 2017Every flash flood warning in 2017

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.