Alert archive / California / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 9, NWS Reno, NV

August 14, 1998Placer County, California

NWS Reno, NV issued this severe thunderstorm warning at Aug 14, 1998, 5:00 PM PDT for Placer County, California. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 14, 1998, 5:00 PM PDT (00:00 UTC)
Expired
Aug 14, 1998, 9:00 PM PDT
In force
4 hr
Issued by
NWS Reno, NV
Area
Whole counties

County Placer County, CA

The radar

The Beale AFB radar (KBBX), 92 km from the middle of the area, began a volume at 00:03 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

Oakland, CA (KOAK), launched 00:00Z, 0.0 hours before the alert went out and 197 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, Oakland, CA at 00:00Z on 1998-08-15Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Oakland, CA at 00:00Z on 1998-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -34 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1934 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
-34 m²/s²
0-3 km storm-relative helicity
-5 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.

584 
WUUS1 KRNO 150006  RRA
SVRRNO
CAC061-150030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE RENO NV                                  
500 PM PDT FRI AUG 14 1998

...SEVERE THUNDERSTORM WARNING FOR PLACER COUNTY ALLOWED TO EXPIRE...

...STRONG THUNDERSTORMS CONTINUE ALONG THE SIERRA CREST...

THE STRONG THUNDERSTORM OVER EAST CENTRAL PLACER COUNTY HAS WEAKENED
AND SO THE SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

THE PLACER COUNTY SHERIFFS OFFICE ALONG WITH SEVERAL OTHER SPOTTERS
REPORTED MARBLE-SIZED HAIL NEAR THE SQUAW VALLEY AREA LATE THIS
AFTERNOON.  PORTIONS OF HIGHWAY 89 REPORTEDLY WERE BRIEFLY COVERED
WITH HAIL.  VERY HEAVY RAIN HAS ALSO BEEN REPORTED WITH THESE STORMS.
AN URBAN AND SMALL STREAM FLOOD ADVISORY REMAINS IN EFFECT UNTIL 9 PM
PDT FOR THE GREATER LAKE TAHOE AREA.

DOPPLER RADAR INDICATED SEVERAL THUNDERSTORMS CONTINUING TO DEVELOP
ALONG THE SIERRA CREST MAINLY FROM LAKE TAHOE NORTHWARD INTO SIERRA
COUNTY. HEAVY RAIN...HAIL AND STRONG GUSTY WINDS ARE LIKELY THROUGH
THE REST OF THE AFTERNOON ALONG THE SIERRA.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 57 MPH 
...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. BOATERS
ARE URGED TO BE PREPARED FOR STRONG AND GUSTY WINDS OVER OPEN WATER...
AND SEEK SAFE HARBOR IF CONDITIONS BECOME SEVERE.

Nearby

Severe Thunderstorm Warnings in California, 1998Every severe thunderstorm warning in 1998

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.