Alert archive / Nevada / Flash Flood Warnings in 2018

Flash Flood Warning 9, NWS Reno, NV

July 21, 2018Washoe County, Nevada

NWS Reno, NV issued this flash flood warning at Jul 21, 2018, 4:57 PM PDT for Washoe County, Nevada. It was in force for 2 hr. 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 21, 2018, 4:57 PM PDT (23:57 UTC)
Expired: Jul 21, 2018, 7:00 PM PDT
In force: 2 hr
Issued by: NWS Reno, NV
Area: Storm-based polygon
Flood severity: None

County Washoe County, NV

The radar

The Reno radar (KRGX), 31 km from the middle of the area, began a volume at 23:59 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

Reno, NV (KREV), launched 12:00Z, 12.0 hours before the alert went out and 133 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

439 
WGUS55 KREV 212357
FFWREV
NVC031-220200-
/O.NEW.KREV.FF.W.0009.180721T2357Z-180722T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Reno has issued a

* Flash Flood Warning for...
  Southern Washoe County in western Nevada...

* Until 700 PM PDT.

* At 454 PM PDT, Doppler radar indicated thunderstorms from 
  Winnemucca Ranch Road northward to Pyramid Lake are producing very 
  heavy rain. Up to one inch of rain has already fallen in the 
  Sutcliffe area. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Sutcliffe, Virginia Peak, Highway 445 north of Spanish Springs and 
  Highway 446. 

Excessive rainfall over the Tule burn scar may result in debris 
flows over Highway 446. 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 4019 11962 3975 11945 3971 11970 4013 11987

$$

Brong

1 follow-up statement

386 
WGUS75 KREV 220047
FFSREV

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

NVC031-220200-
/O.CON.KREV.FF.W.0009.000000T0000Z-180722T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Washoe NV-
547 PM PDT SAT JUL 21 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 PM PDT FOR
THE PYRAMID LAKE AREA OF WASHOE COUNTY...

At 546 PM PDT, Doppler radar indicated thunderstorms continue to 
produce heavy rain in the Pyramid Lake area over the Tule Burn Scar 
along Highway 445 north of Sutcliffe and along Highway 447 near the 
Tohakum burn scar.

Excessive rainfall over the burn scars may result in debris flows 
impacting Highways 445 and 447. 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 4019 11962 3975 11945 3971 11970 4013 11987

$$

Brong

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 12:30 PM PDT	Special Weather Statement	REV	Douglas, Lyon, Storey	3 hr
Jul 21, 1:47 PM PDT	Areal Flood Advisory	REV	Douglas	48 hr
Jul 21, 2:41 PM PDT	Flash Flood Warning	REV	Douglas	5 hr
Jul 21, 3:29 PM PDT	Areal Flood Advisory	REV	Storey, Washoe	2 hr
Jul 21, 3:32 PM PDT	Areal Flood Advisory	REV	Lyon	3 hr
Jul 21, 3:44 PM PDT	Special Weather Statement	REV		31 min
Jul 21, 3:50 PM PDT	Flash Flood Warning	REV	Storey, Washoe	4 hr
Jul 21, 4:08 PM PDT	Special Weather Statement	REV	Douglas	52 min

Nearby

Flash Flood Warnings in Nevada, 2018 Every 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.