Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 71, NWS Las Vegas, NV

August 3, 2017San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 3, 2017, 7:41 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, 7:41 AM PDT (14:41 UTC)
Expired
Aug 3, 2017, 10:45 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), 148 km from the middle of the area, began a volume at 14:42 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.

What was reported inside it

TimeReportWhereRemark
Aug 3, 8:27 AM PDTFLASH FLOOD10 Nnw Vidal Junction, CACHP REPORTS US 95 APPROXIMATELY 12 MILES NORTH OF VIDAL JUNCTION IS COMPLETELY FLOODED WITH VEHICLES GETTING STUCK.

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, 2.7 hours before the alert went out and 214 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°0°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.

967 
WGUS55 KVEF 031441
FFWVEF
CAC071-031745-
/O.NEW.KVEF.FF.W.0071.170803T1441Z-170803T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
741 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 1045 AM PDT

* At 740 AM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain along Highway 95 between Needles and Vidal Junction. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Highway 95 At Mile Marker 29, Black Meadow Landing Campground, 
  Earp and Big River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3408 11446 3421 11445 3423 11499 3482 11505
      3480 11461 3478 11456 3471 11447 3461 11443
      3459 11444 3452 11438 3446 11439 3445 11434
      3436 11423 3436 11419 3430 11414 3426 11413
      3426 11416 3417 11425

$$

BP
3 follow-up statements
835 
WGUS75 KVEF 031550
FFSVEF

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

CAC071-031745-
/O.CON.KVEF.FF.W.0071.000000T0000Z-170803T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
850 AM PDT THU AUG 3 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 AM PDT FOR
SOUTHEASTERN SAN BERNARDINO COUNTY...

At 847 AM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area.  Flash flooding is expected to begin
shortly.

Some locations that will experience flooding include...
Highway 95 At Mile Marker 29, Parker Dam, Needles, Black Meadow
Landing Campground, Earp and Big River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3408 11446 3421 11445 3423 11499 3482 11505
      3480 11461 3478 11456 3471 11447 3461 11443
      3459 11444 3452 11438 3446 11439 3445 11434
      3436 11423 3436 11419 3430 11414 3426 11413
      3426 11416 3417 11425

$$

DSB
958 
WGUS75 KVEF 031645
FFSVEF

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

CAC071-031745-
/O.CON.KVEF.FF.W.0071.000000T0000Z-170803T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
945 AM PDT THU AUG 3 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 AM PDT FOR
SOUTHEASTERN SAN BERNARDINO COUNTY...

At 945 AM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area.  Flash flooding is expected to begin
shortly.

Some locations that will experience flooding include...
Highway 95 At Mile Marker 29, Parker Dam, Needles, Black Meadow
Landing Campground, Earp and Big River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3408 11446 3421 11445 3423 11499 3482 11505
      3480 11461 3478 11456 3471 11447 3461 11443
      3459 11444 3452 11438 3446 11439 3445 11434
      3436 11423 3436 11419 3430 11414 3426 11413
      3426 11416 3417 11425

$$

DSB
707 
WGUS75 KVEF 031739
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
1039 AM PDT THU AUG 3 2017

CAC071-031746-
/O.EXP.KVEF.FF.W.0071.000000T0000Z-170803T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
1039 AM PDT THU AUG 3 2017

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN SAN BERNARDINO COUNTY
WILL EXPIRE AT 1045 AM PDT...

Earlier reported flooding on US 95 has ended so the Flash Flood 
Warning will be allowed to expire Flooding is no longer expected to 
pose a threat at this time. Showers and thunderstorms are expected 
periodically through the rest of the day.  Please continue to heed 
any remaining road closures.

LAT...LON 3408 11446 3421 11445 3423 11499 3482 11505
      3480 11461 3478 11456 3471 11447 3461 11443
      3459 11444 3452 11438 3446 11439 3445 11434
      3436 11423 3436 11419 3430 11414 3426 11413
      3426 11416 3417 11425

$$

DSB

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, 6:02 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.