Alert archive / California / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 16, NWS Sacramento, CA

August 21, 2013Nevada County, Plumas County, Sierra County, California

NWS Sacramento, CA issued this severe thunderstorm warning at Aug 21, 2013, 3:38 PM PDT for Nevada County, Plumas County, Sierra County, California. It was in force for 22 min. 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 21, 2013, 3:38 PM PDT (22:38 UTC)
Expired
Aug 21, 2013, 4:00 PM PDT
In force
22 min
Issued by
NWS Sacramento, CA
Area
Storm-based polygon

Counties Nevada County, CA, Plumas County, CA, Sierra County, CA

The radar

The Beale AFB radar (KBBX), 81 km from the middle of the area, began a volume at 22:39 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 215 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 2013-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 17 joules per kilogram.LCLLFCEL10008507005003002001001 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, Reno, NV at 12:00Z on 2013-08-21The 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
17 J/kg
Mixed-layer CIN
-320 J/kg
Mixed-layer LCL
2055 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
7 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sacramento, CA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 21, 3:36 PM PDT, 2 minutes earlier.

Area forecast discussion, Aug 21, 3:36 PM PDT, 2 minutes before
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Hazardous weather outlook, Aug 21, 5:35 AM PDT, 10 hours 3 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SACRAMENTO CA
535 AM PDT WED AUG 21 2013

CAZ013>019-063-064-066>069-220045-
SHASTA LAKE AREA / NORTHERN SHASTA COUNTY-
BURNEY BASIN / EASTERN SHASTA COUNTY-NORTHERN SACRAMENTO VALLEY-
CENTRAL SACRAMENTO VALLEY-SOUTHERN SACRAMENTO VALLEY-
CARQUINEZ STRAIT AND DELTA-NORTHERN SAN JOAQUIN VALLEY-
MOUNTAINS SOUTHWESTERN SHASTA COUNTY TO NORTHERN LAKE COUNTY-
CLEAR LAKE/SOUTHERN LAKE COUNTY-
NORTHEAST FOOTHILLS/SACRAMENTO VALLEY-MOTHERLODE-
WESTERN PLUMAS COUNTY/LASSEN PARK-
WEST SLOPE NORTHERN SIERRA NEVADA-
535 AM PDT WED AUG 21 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR INTERIOR NORTHERN CALIFORNIA.

.DAY ONE...TODAY

ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TODAY. FREQUENT
LIGHTNING...BRIEF HEAVY RAIN AND GUSTY WINDS MAY ACCOMPANY STRONGER
STORMS.

* RED FLAG WARNING...........SEE WWUS86 KSTO - RFWSTO FOR DETAILS *

.DAYS TWO THROUGH SEVEN... WEDNESDAY THROUGH MONDAY

THUNDERSTORMS MAY CONTINUE INTO THURSDAY AS THE UPPER LOW MOVES
THROUGH THE AREA. FREQUENT LIGHTNING...BRIEF HEAVY RAIN AND GUSTY
WINDS MAY ACCOMPANY STRONGER STORMS. DRY WEATHER AND NEAR NORMAL
TEMPERATURES ARE EXPECTED FRIDAY INTO EARLY NEXT WEEK.

* RED FLAG WARNING...........SEE WWUS86 KSTO - RFWSTO FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS TO THEIR LOCAL NATIONAL WEATHER SERVICE OFFICE.

THE LATEST WEATHER INFORMATION IS AVAILABLE AT
WEATHER.GOV/SACRAMENTO

INTERACT WITH US VIA SOCIAL MEDIA AT
FACEBOOK.COM/NWS.SACRAMENTO
TWITTER.COM/NWSSACRAMENTO

In the hours before

Special weather statement, Aug 21, 3:00 PM PDT, 38 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
300 PM PDT WED AUG 21 2013

CAZ013-014-068-212245-
BURNEY BASIN / EASTERN SHASTA COUNTY CA-SHASTA LAKE AREA / NORTHERN
SHASTA COUNTY CA-WESTERN PLUMAS COUNTY/LASSEN PARK CA-
300 PM PDT WED AUG 21 2013

THE NATIONAL WEATHER SERVICE IN SACRAMENTO HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  EAST CENTRAL SHASTA COUNTY IN NORTHERN CALIFORNIA

UNTIL 345 PM PDT

AT 254 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 6 MILES NORTH OF MANZANITA LAKE..MOVING NORTH AT
5 MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH FREQUENT DANGEROUS LIGHTNING.

LOCATIONS IMPACTED INCLUDE...
   BURNEY...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 4090 12182 4097 12151 4083 12135 4047 12134
      4047 12176
TIME...MOT...LOC 2200Z 164DEG 15KT 4064 12155

CS
Local storm report, Aug 21, 3:19 PM PDT, 19 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SACRAMENTO CA
319 PM PDT WED AUG 21 2013

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0318 PM     HAIL             MANZANITA LAKE          40.54N 121.57W
08/21/2013  E1.00 INCH       SHASTA             CA   PARK/FOREST SERVI

            A LOT OF 1" HAIL AND HEAVY RAIN OBSERVED

&&

IRIS SYSTEM

The office that day

Everything else NWS Sacramento, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 5:23 PM PDTSpecial Weather StatementSTOEl Dorado52 min
Aug 21, 2:29 PM PDTSevere Thunderstorm WarningSTONevada, Placer, Sierra46 min
Aug 21, 2:46 PM PDTSevere Thunderstorm WarningSTOPlumas44 min
Aug 21, 3:00 PM PDTSpecial Weather StatementSTOShasta45 min
Aug 21, 3:18 PM PDTSevere Thunderstorm WarningSTOShasta42 min
Aug 21, 4:16 PM PDTSpecial Weather StatementSTOSierra29 min
Aug 21, 4:27 PM PDTSpecial Weather StatementSTO48 min

Nearby

Severe Thunderstorm Warnings in California, 2013Every severe thunderstorm warning in 2013

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.