Alert archive / California / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 13, NWS Reno, NV

August 2, 2017Placer County, California

NWS Reno, NV issued this severe thunderstorm warning at Aug 2, 2017, 3:37 PM PDT for Placer County, California. It was in force for 23 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
Aug 2, 2017, 3:37 PM PDT (22:37 UTC)
Expired
Aug 2, 2017, 4:00 PM PDT
In force
23 min
Issued by
NWS Reno, NV
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Placer County, CA

The radar

The Reno radar (KRGX), 87 km from the middle of the area, began a volume at 22:38 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, 10.6 hours before the alert went out and 177 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 2017-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 39 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, Reno, NV at 12:00Z on 2017-08-02The 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
39 J/kg
Mixed-layer CIN
-322 J/kg
Mixed-layer LCL
3192 m above ground
0-6 km bulk shear
2 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
-9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

214 
WUUS55 KREV 022237
SVRREV
CAC061-022300-
/O.NEW.KREV.SV.W.0013.170802T2237Z-170802T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Reno NV
337 PM PDT WED AUG 2 2017

The National Weather Service in Reno has issued a

* Severe Thunderstorm Warning for...
  Placer County in central California...

* Until 400 PM PDT

* At 336 PM PDT, a severe thunderstorm was located near Northstar, or
  near Squaw Valley, and is nearly stationary.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, fencing, and trees. Dust storms 
           resulting in serious accidents. 

* Locations impacted include...
  Alpine Meadows, Squaw Valley, Tahoe City, Northstar, Granite Flat
  Campground, Ca 89 At Placer-Nevada Co Line, Squaw Valley Ski Area,
  Silver Creek Campground, Northstar Ski Area and Sunnyside-Tahoe
  City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3931 12027 3931 12009 3915 12014 3917 12024
      3919 12026 3922 12027
TIME...MOT...LOC 2236Z 359DEG 2KT 3925 12017 

HAIL...1.00IN
WIND...60MPH
 
$$
2 follow-up statements
150 
WWUS55 KREV 022243
SVSREV

Severe Weather Statement
National Weather Service Reno NV
343 PM PDT WED AUG 2 2017

CAC061-022300-
/O.CON.KREV.SV.W.0013.000000T0000Z-170802T2300Z/
Placer CA-
343 PM PDT WED AUG 2 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM PDT
FOR PLACER COUNTY...

At 342 PM PDT, a severe thunderstorm was located near Northstar, or
near Squaw Valley, and is nearly stationary.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, fencing, and trees. 

Locations impacted include...
Alpine Meadows, Squaw Valley, Tahoe City, Northstar, Granite Flat
Campground, Ca 89 At Placer-Nevada Co Line, Squaw Valley Ski Area,
Silver Creek Campground, Northstar Ski Area and Sunnyside-Tahoe City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3931 12027 3931 12009 3915 12014 3917 12024
      3919 12026 3922 12027
TIME...MOT...LOC 2242Z 087DEG 1KT 3925 12018 

HAIL...1.00IN
WIND...60MPH
 
$$
639 
WWUS55 KREV 022257
SVSREV

Severe Weather Statement
National Weather Service Reno NV
357 PM PDT WED AUG 2 2017

CAC061-022307-
/O.EXP.KREV.SV.W.0013.000000T0000Z-170802T2300Z/
Placer CA-
357 PM PDT WED AUG 2 2017

...THE SEVERE THUNDERSTORM WARNING FOR PLACER COUNTY WILL EXPIRE AT
400 PM PDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire. However small hail
is still possible with this thunderstorm.

LAT...LON 3931 12027 3931 12009 3915 12014 3917 12024
      3919 12026 3922 12027
TIME...MOT...LOC 2257Z 359DEG 2KT 3924 12018 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 2:57 AM PDTExcessive Heat WarningREVLassen, Modoc, Plumas, Sierra38 hr
Aug 2, 2:45 PM PDTSpecial Weather StatementREVAlpine, Lassen2 hr
Aug 2, 4:41 PM PDTSevere Thunderstorm WarningREVEl Dorado, Placer34 min

Nearby

Severe Thunderstorm Warnings in California, 2017Every severe thunderstorm 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.