Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 7, NWS Las Vegas, NV

July 13, 2012San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Jul 13, 2012, 4:09 PM PDT for San Bernardino County, California. It was in force for 2 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
Jul 13, 2012, 4:09 PM PDT (23:09 UTC)
Expired
Jul 13, 2012, 6:15 PM PDT
In force
2 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), 111 km from the middle of the area, began a volume at 23:12 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 12:00Z, 11.2 hours before the alert went out and 188 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 12:00Z on 2012-07-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 12:00Z on 2012-07-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2268 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
44 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.

789 
WGUS55 KVEF 132309
FFWVEF
CAC071-140115-
/O.NEW.KVEF.FF.W.0007.120713T2309Z-120714T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
409 PM PDT FRI JUL 13 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 615 PM PDT.

* AT 400 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM 10 MILES SOUTHEAST OF ESSEX...
  OR 32 MILES SOUTHEAST OF MITCHELL CAVERNS. THE STORM PRODUCING VERY
  HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  ESSEX AND THE EXTREME EASTERN PORTION OF THE NATIONAL TRAILS
  HIGHWAY.

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 3478 11523 3482 11499 3477 11477 3449 11505
      3468 11537

$$

JENSEN
2 follow-up statements
926 
WGUS75 KVEF 132357
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
457 PM PDT FRI JUL 13 2012

CAC071-140115-
/O.CON.KVEF.FF.W.0007.000000T0000Z-120714T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
457 PM PDT FRI JUL 13 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM PDT FOR EAST
CENTRAL SAN BERNARDINO COUNTY...

AT 447 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A THUNDERSTORM WHICH IS LIKELY PRODUCING LOCALLY HEAVY 
RAINFALL. THIS STORM WAS LOCATED NEAR ESSEX...OR 22 MILES SOUTHEAST 
OF MITCHELL CAVERNS.

THE THUNDERSTORM IS NEARLY STATIONARY AND IS CURRENTLY 
DECREASING...HOWEVER ANY ADDITIONAL RAINFALL WILL ADD TO THAT WHICH 
HAS ALREADY FALLEN AND INCREASE RUNOFF.

LOCATIONS IMPACTED INCLUDE...
ESSEX AND THE EXTREME EASTERN PORTION OF THE NATIONAL TRAILS   
HIGHWAY.

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 3478 11523 3482 11499 3477 11477 3449 11505
      3468 11537

$$

JENSEN
797 
WGUS75 KVEF 140108
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
608 PM PDT FRI JUL 13 2012

CAC071-140115-
/O.EXP.KVEF.FF.W.0007.000000T0000Z-120714T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
608 PM PDT FRI JUL 13 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 615 PM PDT FOR EAST CENTRAL
SAN BERNARDINO COUNTY...

THUNDERSTORMS HAVE DECREASED OVER THE WARNED AREA. HOWEVER RUNOFF 
FROM THE THUNDERSTORMS WILL LIKELY BE FLOWING THROUGH NORMALLY DRY 
WASHES AND PONDING OF WATER MAY BE ENCOUNTERED THROUGH THE NIGHT. 
THE MAIN AREA OF CONCERN WILL BE ALONG THE NATIONAL TRAILS HIGHWAY 
NEAR ESSEX.

ADDITIONAL THUNDERSTORMS WHICH HAVE FORMED TO THE SOUTH OF THE AREA 
MAY MOVE OVER THE SAME REGION LATER THIS EVENING AND WILL BE CLOSELY 
MONITORED.

LAT...LON 3478 11523 3482 11499 3477 11477 3449 11505
      3468 11537

$$

JENSEN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 13, 6:03 AM PDTAreal Flood AdvisoryVEFSan Bernardino117 min
Jul 13, 7:03 AM PDTAreal Flood AdvisoryVEFSan Bernardino117 min
Jul 13, 1:22 PM PDTFlash Flood WarningVEFInyo113 min
Jul 13, 2:55 PM PDTFlash Flood WarningVEFInyo2 hr
Jul 13, 3:51 PM PDTFlash Flood WarningVEFSan Bernardino114 min
Jul 13, 4:16 PM PDTFlash Flood WarningVEFInyo119 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.