Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 10, NWS Reno, NV

August 8, 2017Plumas County, California

NWS Reno, NV issued this flash flood warning at Aug 8, 2017, 6:15 PM PDT for Plumas County, California. It was in force for 3 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
Aug 8, 2017, 6:15 PM PDT (01:15 UTC)
Expired
Aug 8, 2017, 9:15 PM PDT
In force
3 hr
Issued by
NWS Reno, NV
Area
Storm-based polygon
Flood severity
None

County Plumas County, CA

The radar

The Reno radar (KRGX), 72 km from the middle of the area, began a volume at 01:15 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 00:00Z, 1.3 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, Reno, NV at 00:00Z on 2017-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 212 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2017-08-09The 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
212 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
3011 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
4 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

321 
WGUS55 KREV 090115
FFWREV
CAC063-090415-
/O.NEW.KREV.FF.W.0010.170809T0115Z-170809T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Reno NV
615 PM PDT TUE AUG 8 2017

The National Weather Service in Reno has issued a

* Flash Flood Warning for...
  Plumas County in northern California...

* Until 915 PM PDT

* At 611 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain across northeast Plumas County, mainly northwest of 
  Frenchman Lake in the drainages on either side of Dixie Mountain. 
  Doppler radar estimates 1 to 2 inches of rain has already fallen. 
  The storms are moving very slowly and reforming in the same area. 
  Flash flooding is expected to begin shortly. Small hail is also 
  likely in these storms.

* Flash flooding will remain over mainly rural areas of Plumas 
  County. 

Additional rainfall amounts of 0.75 inches to 1 inch are possible in 
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3988 12021 3990 12032 3998 12034 4004 12031
      4007 12024 4000 12020

$$
2 follow-up statements
205 
WGUS75 KREV 090143
FFSREV

Flash Flood Statement
National Weather Service Reno NV
643 PM PDT TUE AUG 8 2017

CAC063-090415-
/O.CON.KREV.FF.W.0010.000000T0000Z-170809T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Plumas CA-
643 PM PDT TUE AUG 8 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM PDT FOR
PLUMAS COUNTY...

At 640 PM PDT, thunderstorms with heavy and some small hail continue 
to develop over move over the area around Frenchman lake and Dixie 
Mountain. Rainfall estimates from doppler radar indicate in excess 
of 1.50 inches has fallen in the area between Frenchman Lake and 
Dixie Mountain. Flash flooding is expected to begin shortly.

Flash flooding will remain over mainly rural areas of Plumas County.

Additional rainfall amounts of up to 1 inch of rain are possible in 
the warned area as storms continue to redevelop and move over areas 
that have already received heavy rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3988 12021 3990 12032 3998 12034 4004 12031
      4007 12024 4000 12020

$$
519 
WGUS75 KREV 090257
FFSREV

Flash Flood Statement
National Weather Service Reno NV
757 PM PDT TUE AUG 8 2017

CAC063-090306-
/O.CAN.KREV.FF.W.0010.000000T0000Z-170809T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Plumas CA-
757 PM PDT TUE AUG 8 2017

...THE FLASH FLOOD WARNING FOR PLUMAS COUNTY IS CANCELLED...

The heavy rain has ended and runoff from the storms should be 
decreasing. Flooding is no longer expected to pose a threat. 

LAT...LON 3988 12021 3990 12032 3998 12034 4004 12031
      4007 12024 4000 12020

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 8, 5:30 PM PDTSpecial Weather StatementREVPlumas45 min
Aug 8, 8:49 PM PDTSpecial Weather StatementREVLassen116 min
Aug 9, 3:14 AM PDTFlash Flood WatchREVLassen, Modoc, Plumas, Sierra19 hr
Aug 9, 2:33 PM PDTAreal Flood AdvisoryREVSierra3 hr
Aug 9, 2:48 PM PDTSpecial Weather StatementREVAlpine, Lassen57 min

Nearby

Flash Flood Warnings in California, 2017Every flash flood warning in 2017

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.