Alert archive / California / Flash Flood Warnings in 2011

Flash Flood Warning 91, NWS Las Vegas, NV

September 13, 2011San Bernardino County, California; Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Sep 13, 2011, 9:56 AM PDT for San Bernardino County, California; Mohave County, Arizona. It was in force for 83 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, 9:56 AM PDT (16:56 UTC)
Expired
Sep 13, 2011, 11:19 AM PDT
In force
83 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

Counties Mohave County, AZ, San Bernardino County, CA

The radar

The Las Vegas radar (KESX), 102 km from the middle of the area, began a volume at 16:57 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, 4.9 hours before the alert went out and 193 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.

502 
WGUS55 KVEF 131656
FFWVEF
AZC015-CAC071-131945-
/O.NEW.KVEF.FF.W.0091.110913T1656Z-110913T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EXTREME SOUTHWESTERN MOHAVE COUNTY IN NORTHWEST ARIZONA...
  EAST CENTRAL SAN BERNARDINO COUNTY IN SOUTHERN CALIFORNIA...

* UNTIL 1245 PM PDT/1245 PM MST/.

* AT 948 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
VERY HEAVY RAIN FROM A THUNDERSTORM NEAR NEEDLES ALONG HIGHWAY 95 
AND INTERSTATE 40...SLOWLY MOVING TO THE NORTH. 

* LOCATIONS IMPACTED INCLUDE...NEEDLES...NEEDLES KOA 
CAMPGROUND...AND MOHAVE VALLEY. LOW WATER CROSSINGS LOCATED ALONG 
NEEDLES HIGHWAY AND THE PAIUTE WASH...ALONG WITH SEVERAL LOW WATER 
CROSSINGS ALONG ROUTE 95 BETWEEN MILE MARKERS 210 AND 220 WILL 
LIKELY BE SIGNIFICANTLY IMPACTED.

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 TWITTER #NWSVEGAS.


&&

LAT...LON 3480 11468 3493 11475 3497 11454 3484 11447
      3470 11443 3469 11465

$$
KENNEDY
1 follow-up statement
292 
WGUS75 KVEF 131819
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1119 AM PDT TUE SEP 13 2011

AZC015-CAC071-131823-
/O.CAN.KVEF.FF.W.0091.000000T0000Z-110913T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-SAN BERNARDINO CA-
1119 AM PDT TUE SEP 13 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EAST CENTRAL SAN
BERNARDINO AND EXTREME SOUTHWESTERN MOHAVE COUNTIES...

ALTHOUGH LIGHT MODERATE RAINFALL IS EXPECTED TO CONTINUE THROUGH 
NOON OVER NEEDLES AND ALONG PORTIONS OF INTERSTATE 40 AND HIGHWAY 95 
BETWEEN TOPOCK AND MOHAVE VALLEY...RECENT REPORTS FROM THE AREA 
INDICATE ONLY MINOR ROADWAY FLOODING AT THIS TIME. MINOR ROADWAY 
FLOODING WILL LIKELY CONTINUE THROUGH NOON TODAY.

LAT...LON 3480 11468 3493 11475 3497 11454 3484 11447
      3470 11443 3469 11465

$$

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, 10:22 AM PDTFlash Flood WarningVEFSan Bernardino113 min
Sep 13, 11:09 AM PDTFlash Flood WarningVEFSan Bernardino27 min
Sep 13, 4:33 AM PDTAreal Flood AdvisoryVEFMohave41 min
Sep 13, 5:10 AM PDTFlash Flood WarningVEFMohave2 hr
Sep 13, 5:32 AM PDTAreal Flood AdvisoryVEFMohave118 min
Sep 13, 8:23 AM PDTFlash Flood WarningVEFMohave112 min

Nearby

Flash Flood Warnings in California, 2011Flash Flood Warnings in Arizona, 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.