Alert archive / California / Flash Flood Warnings in 2011

Flash Flood Warning 92, NWS Las Vegas, NV

September 13, 2011San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Sep 13, 2011, 10:22 AM PDT for San Bernardino County, California. It was in force for 113 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
Sep 13, 2011, 10:22 AM PDT (17:22 UTC)
Expired
Sep 13, 2011, 12:15 PM PDT
In force
113 min
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), 53 km from the middle of the area, began a volume at 17:23 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, 5.4 hours before the alert went out and 109 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 2011-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 239 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 2011-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 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
239 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
1707 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

712 
WGUS55 KVEF 131722
FFWVEF
CAC071-131915-
/O.NEW.KVEF.FF.W.0092.110913T1722Z-110913T1915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1022 AM PDT TUE SEP 13 2011

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 1215 PM PDT.

* AT 1014 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM 18 MILES SOUTH OF NIPTON AND
  IVANPAH ROADS...OR NEAR CIMA. THE STORM PRODUCING VERY HEAVY RAIN
  WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...EASTERN SAN BERNARDINO COUNTY SOUTH 
OF INTERSTATE 15 AND NIPTON...ALONG IVANPAH ROAD NORTH OF CIMA.

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 TWITTER #NWSVEGAS.

&&

LAT...LON 3544 11549 3552 11541 3557 11539 3556 11534
      3537 11511 3520 11522 3519 11535

$$
KENNEDY
1 follow-up statement
133 
WGUS75 KVEF 131909
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1209 PM PDT TUE SEP 13 2011

CAC071-131919-
/O.EXP.KVEF.FF.W.0092.000000T0000Z-110913T1915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1209 PM PDT TUE SEP 13 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1215 PM PDT FOR
NORTHEASTERN SAN BERNARDINO COUNTY...

ALTHOUGH MODERATE RAIN IS EXPECTED TO CONTINUE TO FALL THROUGH THE 
EARLY AFTERNOON ACROSS THE AREA...THE THREAT OF FLASH FLOODING HAS 
DECREASED SIGNIFICANTLY AND THE WARNING WILL BE ALLOWED TO EXPIRE. 
MOTORISTS ALONG MORNINGSTAR AND IVANPAH ROAD SHOULD CONTINUE TO TAKE 
CARE THOUGH...ESPECIALLY WHERE IVANPAH ROAD MEETS WILLOW WASH.

LAT...LON 3544 11549 3552 11541 3557 11539 3556 11534
      3537 11511 3520 11522 3519 11535

$$

KENNEDY

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 3:36 AM PDTFlash Flood WatchVEFSan Bernardino15 hr
Sep 13, 5:46 AM PDTAreal Flood AdvisoryVEFSan Bernardino119 min
Sep 13, 6:31 AM PDTFlash Flood WarningVEFSan Bernardino86 min
Sep 13, 8:01 AM PDTFlash Flood WarningVEFSan Bernardino119 min
Sep 13, 9:09 AM PDTFlash Flood WarningVEFSan Bernardino111 min
Sep 13, 9:56 AM PDTFlash Flood WarningVEFSan Bernardino83 min
Sep 13, 11:09 AM PDTFlash Flood WarningVEFSan Bernardino27 min

Nearby

Flash Flood Warnings in California, 2011Every flash flood warning in 2011

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.