Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 154, NWS Las Vegas, NV

August 22, 2012San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Aug 22, 2012, 11:30 AM PDT for San Bernardino County, California. It was in force for 56 min. 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 22, 2012, 11:30 AM PDT (18:30 UTC)
Expired
Aug 22, 2012, 12:26 PM PDT
In force
56 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), 121 km from the middle of the area, began a volume at 18:32 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 22, 11:30 AM PDTFLASH FLOOD1 Ne Joshua Tree, CATHE CALIFORNIA HIGHWAY PATROL REPORTED THAT WATER FLOWED OVER STATE ROUTE 62 NEAR SUNBURST STREET LEAVING MUD AND DEBRIS ON THE HIGHWAY.

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

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 6.5 hours before the alert went out and 168 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°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.

696 
WGUS55 KVEF 221830
FFWVEF
CAC071-222030-
/O.NEW.KVEF.FF.W.0154.120822T1830Z-120822T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1130 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 130 PM PDT.

* AT 1126 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
  VERY HEAVY RAIN FROM THUNDERSTORMS EXTENDING FROM YUCCA VALLEY TO 
  JOSHUA TREE. THESE STORMS WILL PRODUCE VERY HEAVY RAIN WHICH COULD 
  FLOOD HIGHWAYS 62 AND 247.

* LOCATIONS IMPACTED INCLUDE...
  HIGHWAYS 62 AND 247.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. 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 3407 11649 3413 11649 3420 11644 3429 11645
      3429 11641 3413 11621 3412 11626 3408 11627

$$

MORGAN
1 follow-up statement
517 
WGUS75 KVEF 221926
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1226 PM PDT WED AUG 22 2012

CAC071-221935-
/O.CAN.KVEF.FF.W.0154.000000T0000Z-120822T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1226 PM PDT WED AUG 22 2012

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

AT 1225 PM PDT...RADAR INDICATED THAT HEAVY RAIN HAD ENDED OVER THE 
SOUTHERN END OF HIGHWAY 247 AS WELL AS HIGHWAY 62 WEST OF MILE 
MARKER 24. NO REPORTS OF FLOODING HAD BEEN RECEIVED FROM THIS 
AREA...SO THE FLASH FLOOD WARNING HAS BEEN CANCELLED.

A FLASH FLOOD WARNING REMAINS IN EFFECT FOR AREAS JUST TO THE NORTH 
AND EAST UNTIL 145 PM PDT.

LAT...LON 3407 11649 3413 11649 3420 11644 3429 11645
      3429 11641 3413 11621 3412 11626 3408 11627

$$

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, 11:50 AM PDTFlash Flood WarningVEFSan Bernardino54 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.