Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 155, NWS Las Vegas, NV

August 22, 2012San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 22, 2012, 11:50 AM PDT for San Bernardino County, California. It was in force for 54 min. 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 22, 2012, 11:50 AM PDT (18:50 UTC)
Expired
Aug 22, 2012, 12:44 PM PDT
In force
54 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County San Bernardino County, CA

The radar

The Santa Ana Mts radar (KSOX), 145 km from the middle of the area, began a volume at 18:54 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

San Diego, CA (KNKX), launched 12:00Z, 6.8 hours before the alert went out and 182 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, San Diego, CA at 12:00Z on 2012-08-22Temperature 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, San Diego, CA at 12:00Z on 2012-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 square meters per square second.193958Sfc1 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
596 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
6 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.

851 
WGUS55 KVEF 221850
FFWVEF
CAC071-222045-
/O.NEW.KVEF.FF.W.0155.120822T1850Z-120822T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1150 AM PDT WED AUG 22 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 145 PM PDT.

* AT 1147 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR JOSHUA TREE LAKE 
  CAMPGROUND...OR 11 MILES NORTHWEST OF TWENTYNINE PALMS. THE STORM 
  PRODUCING VERY HEAVY RAIN WAS MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  HIGHWAY 62 BETWEEN JOSHUA TREE AND TWENTYNINE PALMS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. NEVER TRY TO CROSS A FLOODED ROADWAY OR
WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3411 11605 3412 11606 3412 11620 3429 11641
      3438 11617 3411 11600 3411 11601

$$

MORGAN
1 follow-up statement
003 
WGUS75 KVEF 221944
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1244 PM PDT WED AUG 22 2012

CAC071-221953-
/O.CAN.KVEF.FF.W.0155.000000T0000Z-120822T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1244 PM PDT WED AUG 22 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTH CENTRAL SAN
BERNARDINO COUNTY...

AT 1242 PM PDT...RADAR INDICATED THAT HEAVY RAIN HAD MOVED NORTHEAST 
AWAY FROM JOSHUA TREE AND TWENTYNINE PALMS. NO REPORTS OF FLOODING 
HAD BEEN RECEIVED FROM THIS AREA...SO THE FLASH FLOOD WARNING HAS 
BEEN CANCELLED.

LAT...LON 3411 11605 3412 11606 3412 11620 3429 11641
      3438 11617 3411 11600 3411 11601

$$

MORGAN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 7:57 PM PDTSevere Thunderstorm WarningVEFSan Bernardino48 min
Aug 22, 3:53 AM PDTAreal Flood AdvisoryVEFInyo3 hr
Aug 22, 9:19 AM PDTAreal Flood AdvisoryVEFInyo, San Bernardino3 hr
Aug 22, 9:34 AM PDTFlash Flood WarningVEFInyo, San Bernardino116 min
Aug 22, 9:45 AM PDTFlash Flood WarningVEFSan Bernardino2 hr
Aug 22, 10:05 AM PDTSevere Thunderstorm WarningVEFSan Bernardino25 min
Aug 22, 10:45 AM PDTFlash Flood WarningVEFSan Bernardino2 hr
Aug 22, 10:49 AM PDTFlash Flood WarningVEFSan Bernardino116 min
Aug 22, 11:27 AM PDTSevere Thunderstorm WarningVEFSan Bernardino48 min
Aug 22, 11:30 AM PDTFlash Flood WarningVEFSan Bernardino56 min
Aug 22, 11:58 AM PDTFlash Flood WarningVEFSan Bernardino2 hr
Aug 22, 1:03 PM PDTFlash Flood WarningVEFSan Bernardino87 min
Aug 22, 1:42 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 22, 1:47 PM PDTFlash Flood WarningVEFInyo36 min
Aug 22, 1:50 PM PDTFlash Flood WarningVEFSan Bernardino115 min
Aug 22, 1:55 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Aug 22, 2:57 PM PDTFlash Flood WarningVEFInyo2 hr
Aug 22, 3:55 PM PDTFlash Flood WarningVEFInyo65 min

Nearby

Flash Flood Warnings in California, 2012Every flash flood warning in 2012

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.