Alert archive / Nevada / Flash Flood Warnings in 2018

Flash Flood Warning 7, NWS Reno, NV

July 21, 2018Douglas County, Nevada; Mono County, California

NWS Reno, NV issued this flash flood warning at Jul 21, 2018, 2:41 PM PDT for Douglas County, Nevada; Mono County, California. It was in force for 5 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
Jul 21, 2018, 2:41 PM PDT (21:41 UTC)
Expired
Jul 21, 2018, 7:21 PM PDT
In force
5 hr
Issued by
NWS Reno, NV
Area
Storm-based polygon
Flood severity
None

Counties Mono County, CA, Douglas County, NV

The radar

The Reno radar (KRGX), 122 km from the middle of the area, began a volume at 21:42 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
Jul 21, 3:00 PM PDTFLASH FLOOD6 S Holbrook Junction, CACALIFORNIA HIGHWAY PATROL REPORTED A FLASH FLOOD CROSSING THE ROAD WITH TREES AND BOULDERS.

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

The nearest sounding before it

Reno, NV (KREV), launched 12:00Z, 9.7 hours before the alert went out and 155 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, Reno, NV at 12:00Z on 2018-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Reno, NV at 12:00Z on 2018-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2299 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

981 
WGUS55 KREV 212141
FFWREV
CAC051-NVC005-212345-
/O.NEW.KREV.FF.W.0007.180721T2141Z-180721T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Reno NV
241 PM PDT SAT JUL 21 2018

The National Weather Service in Reno has issued a

* Flash Flood Warning for...
  Northern Mono County in northern California...
  Douglas County in western Nevada...

* Until 445 PM PDT.

* At 239 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain along Highway 89 and the Slinkard burn scar. Flash 
  flooding and debris flows have an enhanced probability of 
  occurring. 

* Some locations that will experience flooding include...
  Highways 89 and 395 near the Slinkard burn scar. 

Excessive rainfall over the Slinkard Burn scar will result in debris 
flow. The debris flow can consist of rock, mud, vegetation and other 
loose materials.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3866 11961 3871 11958 3868 11953 3860 11952

$$

Brong
3 follow-up statements
988 
WGUS75 KREV 212221
FFSREV

Flash Flood Statement
National Weather Service Reno NV
321 PM PDT SAT JUL 21 2018

CAC051-NVC005-212345-
/O.CON.KREV.FF.W.0007.000000T0000Z-180721T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mono CA-Douglas NV-
321 PM PDT SAT JUL 21 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM PDT FOR
NORTHERN MONO AND DOUGLAS COUNTIES...

At 318 PM PDT, local law enforcement reported debris flow over 
Highway 89 in the Slinkard burn scar. Boulders and trees are 
blocking the road. 

Rainfall has diminished over the burn scar, but additional 
thunderstorms are possible through this afternoon.

Some locations that will experience flooding include...
Highway 89 in the Slinkard burn scar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3866 11961 3871 11958 3868 11953 3860 11952

$$

Brong
719 
WGUS55 KREV 212319
FFWREV
CAC051-NVC005-220245-
/O.EXT.KREV.FF.W.0007.000000T0000Z-180722T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Reno NV
419 PM PDT SAT JUL 21 2018

The National Weather Service in Reno has extended the

* Flash Flood Warning for...
  Northern Mono County in northern California...
  Douglas County in western Nevada...

* Until 745 PM PDT.

* At 415 PM PDT, additional thunderstorms producing heavy rain are 
  moving north toward the Slinkard Fire burn scar. The burn scar has 
  already produced a debris flow that pushed trees and boulders 
  across Highway 89.

* Some locations that will experience flooding include...
  Topaz Lake and Junction U.S 395 And CA 89. 

Excessive rainfall over the Slinkard Fire burn scar will result in 
debris flows moving toward Highways 395 and 89. Debris flows can 
consist of rock, mud, vegetation and other loose materials.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3866 11961 3871 11958 3868 11953 3860 11952

$$
907 
WGUS75 KREV 220221
FFSREV

Flash Flood Statement
National Weather Service Reno NV
721 PM PDT SAT JUL 21 2018

CAC051-NVC005-220229-
/O.CAN.KREV.FF.W.0007.000000T0000Z-180722T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mono CA-Douglas NV-
721 PM PDT SAT JUL 21 2018

...THE FLASH FLOOD WARNING FOR NORTHERN MONO AND DOUGLAS COUNTIES IS
CANCELLED...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Highway 89 near Monitor Pass remains closed due to an earlier 
debris flow. Please continue to heed any remaining road closures.

LAT...LON 3866 11961 3871 11958 3868 11953 3860 11952

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 12:30 PM PDTSpecial Weather StatementREVDouglas, Lyon, Storey3 hr
Jul 21, 1:47 PM PDTAreal Flood AdvisoryREVDouglas48 hr
Jul 21, 3:29 PM PDTAreal Flood AdvisoryREVStorey, Washoe2 hr
Jul 21, 3:32 PM PDTAreal Flood AdvisoryREVLyon3 hr
Jul 21, 3:44 PM PDTSpecial Weather StatementREV31 min
Jul 21, 3:50 PM PDTFlash Flood WarningREVStorey, Washoe4 hr
Jul 21, 4:08 PM PDTSpecial Weather StatementREVDouglas52 min
Jul 21, 4:57 PM PDTFlash Flood WarningREVWashoe2 hr

Nearby

Flash Flood Warnings in Nevada, 2018Flash 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.