Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 70, NWS Las Vegas, NV

August 3, 2017San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 3, 2017, 6:02 AM PDT for San Bernardino County, California. It was in force for 3 hr. 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 3, 2017, 6:02 AM PDT (13:02 UTC)
Expired
Aug 3, 2017, 9:00 AM 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), 181 km from the middle of the area, began a volume at 13:04 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
Aug 3, 6:45 AM PDTFLASH FLOOD4 Wnw Rice, CACALTRANS REPORTS FLOODING AT SALT MINE NEAR MM103 ON CA 62.

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

The nearest sounding before it

Yuma Prvg Ground, AZ (K1Y7), launched 12:00Z, 1.0 hours before the alert went out and 201 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 12:00Z on 2017-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 643 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, Yuma Prvg Ground, AZ at 12:00Z on 2017-08-03The 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
643 J/kg
Mixed-layer CIN
-190 J/kg
Mixed-layer LCL
1749 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

536 
WGUS55 KVEF 031302
FFWVEF
CAC071-031600-
/O.NEW.KVEF.FF.W.0070.170803T1302Z-170803T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
602 AM PDT THU AUG 3 2017

The National Weather Service in Las Vegas has issued a

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

* Until 900 AM PDT

* At 600 AM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain moving north across the Mohave Desert area. Flash 
  flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Highway 62 and Vidal Junction.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3424 11570 3422 11445 3408 11446 3407 11532
      3412 11552 3407 11555 3409 11560 3403 11560
      3404 11572

$$

AA
1 follow-up statement
525 
WGUS75 KVEF 031428
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
728 AM PDT THU AUG 3 2017

CAC071-031600-
/O.CON.KVEF.FF.W.0070.000000T0000Z-170803T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
728 AM PDT THU AUG 3 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 AM PDT FOR
SOUTHEASTERN SAN BERNARDINO COUNTY...

At 726 AM PDT, Doppler radar continued to indicate thunderstorms 
producing heavy rain across the warned area.  Flash flooding is 
occurring or expected to begin shortly along Highway 62 between 
Vidal Junction and Twentynine Palms. 

Some locations that will experience flooding include...
Vidal Junction and Highway 62.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3424 11570 3422 11445 3408 11446 3407 11532
      3412 11552 3407 11555 3409 11560 3403 11560
      3404 11572

$$

BP

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 5:53 PM PDTFlash Flood WarningVEFInyo2 hr
Aug 2, 7:19 PM PDTSevere Thunderstorm WarningVEFSan Bernardino26 min
Aug 2, 7:36 PM PDTFlash Flood WarningVEFInyo3 hr
Aug 2, 8:09 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 2, 8:19 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 2, 8:57 PM PDTAreal Flood AdvisoryVEFInyo3 hr
Aug 2, 9:54 PM PDTAreal Flood AdvisoryVEFSan Bernardino3 hr
Aug 2, 10:04 PM PDTFlash Flood WarningVEFInyo, San Bernardino3 hr
Aug 2, 11:36 PM PDTAreal Flood AdvisoryVEFSan Bernardino3 hr
Aug 3, 2:27 AM PDTFlash Flood WatchVEFInyo, San Bernardino21 hr
Aug 3, 7:41 AM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 3, 8:59 AM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 3, 2:00 PM PDTFlash Flood WarningVEFSan Bernardino3 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.