Alert archive / California / Flash Flood Warnings in 2011

Flash Flood Warning 4, NWS Reno, NV

July 29, 2011Mono County, California

NWS Reno, NV issued this flash flood warning at Jul 29, 2011, 4:43 PM PDT for Mono County, California. It was in force for 3 hr. 2 reports 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 29, 2011, 4:43 PM PDT (23:43 UTC)
Expired
Jul 29, 2011, 7:45 PM PDT
In force
3 hr
Issued by
NWS Reno, NV
Area
Storm-based polygon
Flood severity
None

County Mono County, CA

The radar

The Reno radar (KRGX), 135 km from the middle of the area, began a volume at 23:43 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 29, 5:35 PM PDTFLASH FLOODWalker, CAFLASH FLOOD REPORTED IN WALKER CANYON WITH ROCKS MOVED ONTO HIGHWAY 395.
Jul 29, 6:34 PM PDTFLASH FLOOD2 Nw Walker, CACHP REPORTS WATER FLOWING ON HIGHWAY 395 SOUTHBOUND LANES NEAR MILL CANYON ROAD WITH BOULDERS ON SHOULDER OF HIGHWAY. DRAINAGE PIPE ALONG HIGHWAY 395 CLOGGED WITH SAND.

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, 11.7 hours before the alert went out and 159 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 2011-07-29Temperature 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 2011-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 square meters per square second.193958Sfc1 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
0 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
128 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

293 
WGUS55 KREV 292343
FFWREV
CAC051-300245-
/O.NEW.KREV.FF.W.0004.110729T2343Z-110730T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RENO NV
443 PM PDT FRI JUL 29 2011

THE NATIONAL WEATHER SERVICE IN RENO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN MONO COUNTY IN CENTRAL CALIFORNIA...  
  THIS INCLUDES THE CITIES OF COLEVILLE AND WALKER...

* UNTIL 745 PM PDT

* AT 429 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WALKER AND 
  COLEVILLE AND HIGHWAY 395 IN THAT VICINITY

STRONG THUNDERSTORM NEAR WALKER AND COLEVILLE CONTINUES TO RAIN 
HEAVILY...WITH RAINFALL RATES EXCEEDING ONE INCH PER HOUR IN THE 
HIGHER TERRAIN WEST OF HIGHWAY 395. HEAVY RAINFALL IN THE MOUNTAINS 
TO THE WEST OF HIGHWAY 395 COULD CAUSE FLASH FLOODING IN OR AROUND 
THE WALKER-COLEVILLE AREA AND ALONG HIGHWAY 395 SOUTH OF TOPAZ AND 
NEAR THE WALKER RIVER CANYON.

FLOODING IS OCCURRING OR IS IMMINENT. IT IS IMPORTANT TO KNOW WHERE
YOU ARE RELATIVE TO STREAMS...RIVERS...OR CREEKS WHICH CAN BECOME
KILLERS IN HEAVY RAINS. CAMPERS AND HIKERS SHOULD AVOID STREAMS OR
CREEKS.

IN HILLY TERRAIN THERE ARE MANY LOW WATER CROSSINGS WHICH ARE 
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS 
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF 
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

LAT...LON 3859 11956 3862 11946 3852 11932 3837 11951

$$

HOON
3 follow-up statements
464 
WGUS75 KREV 300000
FFSREV

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RENO NV
500 PM PDT FRI JUL 29 2011

CAC051-300245-
/O.CON.KREV.FF.W.0004.000000T0000Z-110730T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONO CA-
500 PM PDT FRI JUL 29 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM PDT FOR
NORTHWESTERN MONO COUNTY...

AT 445 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A THUNDERSTORM PRODUCING FLASH FLOODING OVER THE WARNED
AREA.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
WALKER-COLEVILLE...WALKER RIVER CANYON...AND HIGHWAY 395 IN THAT 
VICINITY. 

DRAINAGES INCLUDED IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
MILL CREEK AND THE WEST FORK WALKER RIVER THROUGH THE WALKER RIVER 
CANYON.

FLOODING IS OCCURRING OR IS IMMINENT. IT IS IMPORTANT TO KNOW WHERE
YOU ARE RELATIVE TO STREAMS...RIVERS...OR CREEKS WHICH CAN BECOME
KILLERS IN HEAVY RAINS. CAMPERS AND HIKERS SHOULD AVOID STREAMS OR
CREEKS.

IN HILLY TERRAIN THERE ARE MANY LOW WATER CROSSINGS WHICH ARE 
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS 
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF 
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

LAT...LON 3859 11956 3862 11946 3852 11932 3837 11951

$$

HOON
848 
WGUS75 KREV 300122
FFSREV

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RENO NV
622 PM PDT FRI JUL 29 2011

CAC051-300245-
/O.CON.KREV.FF.W.0004.000000T0000Z-110730T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONO CA-
622 PM PDT FRI JUL 29 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM PDT FOR
NORTHWESTERN MONO COUNTY...

AT 600 PM PDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED A 
THUNDERSTORM PRODUCING FLASH FLOODING OVER THE WARNED AREA. THERE 
ARE REPORTS OF FLASH FLOODING CAUSING ROCKS TO COME DOWN ONTO 
HIGHWAY 395 IN THE WALKER RIVER CANYON. RAIN CONTINUES TO FALL IN 
THE AREA...ALTHOUGH SHOULD BE LETTING UP OVER THE NEXT HOUR OR SO.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
WALKER-COLEVILLE AND THE WALKER RIVER CANYON.

IN HILLY TERRAIN THERE ARE MANY LOW WATER CROSSINGS WHICH ARE 
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS 
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF 
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

LAT...LON 3859 11956 3862 11946 3852 11932 3837 11951

$$

HOON
765 
WGUS75 KREV 300237
FFSREV

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RENO NV
737 PM PDT FRI JUL 29 2011

CAC051-300246-
/O.EXP.KREV.FF.W.0004.000000T0000Z-110730T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONO CA-
737 PM PDT FRI JUL 29 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 745 PM PDT FOR NORTHWESTERN
MONO COUNTY...

THE STORMS THAT EARLIER PROMPTED THE FLASH FLOOD WARNING HAVE
DISSIPATED...WITH A DIMINISHING FLOOD THREAT. REMEMBER THAT MINOR 
FLOODING OF LOW SPOTS MAY CONTINUE FOR SEVERAL HOURS.

LAT...LON 3859 11956 3862 11946 3852 11932 3837 11951

$$

HOON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 3:17 PM PDTSpecial Weather StatementREVMono3 hr

Nearby

Flash Flood Warnings in California, 2011Every flash flood warning in 2011

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.