Alert archive / California / Flash Flood Warnings in 2018

Flash Flood Warning 7, NWS Las Vegas, NV

July 10, 2018San Bernardino County, California

NWS Las Vegas, NV issued this flash flood warning at Jul 10, 2018, 7:48 PM PDT for San Bernardino County, California. It was in force for 98 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
Jul 10, 2018, 7:48 PM PDT (02:48 UTC)
Expired
Jul 10, 2018, 9:26 PM PDT
In force
98 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), 56 km from the middle of the area, began a volume at 02:52 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 00:00Z, 2.8 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 00:00Z on 2018-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 465 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 00:00Z on 2018-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 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
465 J/kg
Mixed-layer CIN
-44 J/kg
Mixed-layer LCL
2502 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

385 
WGUS55 KVEF 110248
FFWVEF
CAC071-110545-
/O.NEW.KVEF.FF.W.0007.180711T0248Z-180711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
748 PM PDT TUE JUL 10 2018

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  Northeastern San Bernardino County in southern California...

* Until 1045 PM PDT.

* At 746 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain over the northern part of the Mojave National Preserve. 
  The heaviest rain was falling over Morning Star Mine Road, and may 
  also flood the wash which crosses Nipton Road.

* Some locations that will experience flooding include...
  Nipton And Ivanpah Roads.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3548 11530 3528 11544 3531 11551 3547 11539

$$

Morgan
2 follow-up statements
815 
WGUS75 KVEF 110343
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
843 PM PDT TUE JUL 10 2018

CAC071-110545-
/O.CON.KVEF.FF.W.0007.000000T0000Z-180711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
843 PM PDT TUE JUL 10 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 PM PDT FOR
NORTHEASTERN SAN BERNARDINO COUNTY...

At 842 PM PDT, Doppler radar indicated that rain had ended over 
Morning Star Mine Road. However, water is likely still flowing in 
washes, and may be flowing over Nipton Road.

Some locations that will experience flooding include...
Nipton And Ivanpah Roads.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3548 11530 3528 11544 3531 11551 3547 11539

$$

Morgan
820 
WGUS75 KVEF 110426
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
926 PM PDT TUE JUL 10 2018

CAC071-110436-
/O.CAN.KVEF.FF.W.0007.000000T0000Z-180711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
926 PM PDT TUE JUL 10 2018

...THE FLASH FLOOD WARNING FOR NORTHEASTERN SAN BERNARDINO COUNTY IS
CANCELLED...

The heavy rain has ended over the Mojave Preserve. Flooding is no 
longer expected to pose a threat. Please continue to heed any 
remaining road closures.

LAT...LON 3548 11530 3528 11544 3531 11551 3547 11539

$$

Morgan

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 11:10 AM PDTAreal Flood AdvisoryVEFSan Bernardino64 min
Jul 11, 11:45 AM PDTFlash Flood WatchVEFInyo, San Bernardino10 hr
Jul 11, 12:03 PM PDTFlash Flood WarningVEFSan Bernardino5 hr
Jul 11, 1:06 PM PDTFlash Flood WarningVEFInyo3 hr
Jul 11, 2:55 PM PDTFlash Flood WarningVEFSan Bernardino2 hr
Jul 11, 3:40 PM PDTFlash Flood WarningVEFInyo2 hr
Jul 11, 4:11 PM PDTFlash Flood WarningVEFSan Bernardino3 hr

Nearby

Flash Flood Warnings in California, 2018Every flash flood warning in 2018

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.