Alert archive / California / Flash Flood Warnings in 2014

Flash Flood Warning 151, NWS Las Vegas, NV

September 8, 2014San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Sep 8, 2014, 9:04 AM PDT for San Bernardino County, California. It was in force for 3 hr. 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
Sep 8, 2014, 9:04 AM PDT (16:04 UTC)
Expired
Sep 8, 2014, 12:00 PM PDT
In force
3 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), 113 km from the middle of the area, began a volume at 16:06 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
Sep 8, 11:30 AM PDTFLASH FLOOD4 Sw Essex, CATRAINED SPOTTER REPORTED A BRIDGE WASHED OUT IN THE AREA OF A WASH ALONG RT. 66, ALONG WITH MUD ACROSS THE ROADS THROUGHOUT THE AREA IN AND AROUND ESSEX.

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

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 4.1 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, Las Vegas, NV at 12:00Z on 2014-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 162 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 2014-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 square meters per square second.19395878Sfc1 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
162 J/kg
Mixed-layer CIN
-138 J/kg
Mixed-layer LCL
1247 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

982 
WGUS55 KVEF 081604
FFWVEF
CAC071-081900-
/O.NEW.KVEF.FF.W.0151.140908T1604Z-140908T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
904 AM PDT MON SEP 8 2014

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL NOON PDT

* AT 900 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM THUNDERSTORMS NEAR ESSEX...OR 25 MILES
  SOUTHEAST OF MITCHELL CAVERNS. THIS AREA OF THUNDERSTORM ACTIVITY
  HAS PRODUCED OVER A HALF OF AN INCH OF RAIN ESPECIALLY SOUTH OF
  ESSEX. RUNOFF INTO WASHES WILL FLOW TOWARD NATIONAL TRAILS HIGHWAY
  RESULTING IN FLASH FLOODING AND DEBRIS WASHING ONTO THE ROADS.
  OTHER ROADS IN THE AREA WILL ALSO BE AT RISK TO FLOOD.

* LOCATIONS IMPACTED INCLUDE...
  ESSEX
  NATIONAL TRAILS HIGHWAY 
  INTERSTATE 40 BETWEEN MILE MARKERS 84 AND 125.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
ROADS. TO ESCAPE RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO
CROSS A FLOODED ROAD OR ENTER A FLOOD CHANNEL. TURN AROUND...DONT
DROWN!

REPORT FLOODING TO THE LAS VEGAS NATIONAL WEATHER SERVICE VIA
FACEBOOK OR TWITTER.

&&

LAT...LON 3476 11561 3507 11490 3473 11487 3441 11560

$$

STACHELSKI
2 follow-up statements
409 
WGUS75 KVEF 081756
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1056 AM PDT MON SEP 8 2014

CAC071-081900-
/O.CON.KVEF.FF.W.0151.000000T0000Z-140908T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1056 AM PDT MON SEP 8 2014

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

AT 1050 AM PDT...RADAR INDICATED THAT THUNDERSTORMS HAD GENERALLY
DECREASED IN INTENSITY IN THE ESSEX AREA. HOWEVER...RUNOFF FROM HEAVY
RAIN THAT FELL EARLIER WILL STILL RESULT IN WATER FLOWING ACROSS LOW 
LYING SPOTS ON ROADS AS WELL AS WATER COLLECTING IN POOR DRAINAGE 
AREAS.

LOCATIONS IMPACTED INCLUDE...
  ESSEX
  NATIONAL TRAILS HIGHWAY 
  INTERSTATE 40 BETWEEN MILE MARKERS 84 AND 125.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
ROADS. TO ESCAPE RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO
CROSS A FLOODED ROAD OR ENTER A FLOOD CHANNEL. TURN AROUND...DONT
DROWN!

REPORT FLOODING TO THE LAS VEGAS NATIONAL WEATHER SERVICE VIA
FACEBOOK OR TWITTER.

&&

LAT...LON 3476 11561 3507 11490 3473 11487 3441 11560

$$

STACHELSKI
005 
WGUS75 KVEF 081857
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1157 AM PDT MON SEP 8 2014

CAC071-081907-
/O.EXP.KVEF.FF.W.0151.000000T0000Z-140908T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN BERNARDINO CA-
1157 AM PDT MON SEP 8 2014

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

THUNDERSTORMS IN THE ESSEX AREA HAVE ENDED. ANY RUNOFF FROM HEAVIER 
THAT RAIN THAT FELL EARLIER SHOULD BE DECREASING. THEREFORE THE 
FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3476 11561 3507 11490 3473 11487 3441 11560

$$

STACHELSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 5:34 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 5:28 AM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 8:53 AM PDTAreal Flood AdvisoryVEFSan Bernardino3 hr
Sep 8, 9:37 AM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 11:33 AM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 11:45 AM PDTAreal Flood AdvisoryVEFInyo, San Bernardino3 hr
Sep 8, 1:20 PM PDTFlash Flood WarningVEFInyo, San Bernardino3 hr
Sep 8, 1:53 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 1:58 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 2:18 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 3:18 PM PDTFlash Flood WarningVEFSan Bernardino3 hr
Sep 8, 3:21 PM PDTFlash Flood WarningVEFSan Bernardino5 hr

Nearby

Flash Flood Warnings in California, 2014Every flash flood warning in 2014

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.