Alert archive / California / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 13, NWS Sacramento, CA

May 20, 2002Calaveras County, California

NWS Sacramento, CA issued this severe thunderstorm warning at May 20, 2002, 2:31 PM PDT for Calaveras County, California. It was in force for 29 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: May 20, 2002, 2:31 PM PDT (21:31 UTC)
Expired: May 20, 2002, 3:00 PM PDT
In force: 29 min
Issued by: NWS Sacramento, CA
Area: Counties, with a storm outline in the text

County Calaveras County, CA

The nearest sounding before it

Oakland, CA (KOAK), launched 12:00Z, 9.5 hours before the alert went out and 139 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 4 J/kg
Mixed-layer CIN: -206 J/kg
Mixed-layer LCL: 592 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: -46 m²/s²
0-3 km storm-relative helicity: -31 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.

000 
WUUS56 KSTO 202131
SVRSAC
CAC009-202200-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SACRAMENTO CA
227 PM PDT MON MAY 20 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CALAVERAS COUNTY IN CALIFORNIA

* VALID UNTIL 300 PM PDT

* AT 216 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A SEVERE THUNDERSTORM 7 MILES SOUTH OF CAMPO SECO...MOVING         
  NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  CAMPO SECO AT 230 PM PDT
  PALOMA...SR49...AND SAN ANDREAS AT 245 PM PDT
  GLENCOE AT 300 PM PDT

VERY LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE
IN THE PATH OF THE STORM...MOVE TO A SUBSTANTIAL SHELTER.

REPORT SIGNIFICANT WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY.
THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE.

LAT...LON 3817 12098 3804 12082 3832 12040 3840 12050

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 11:44 AM PDT	Tornado Warning	STO	Sutter, Yolo	31 min
May 20, 12:00 PM PDT	Severe Thunderstorm Warning	STO	Glenn, Tehama	30 min
May 20, 12:14 PM PDT	Severe Thunderstorm Warning	STO	Sacramento, Yolo	31 min
May 20, 12:19 PM PDT	Tornado Warning	STO	Sutter, Yolo	26 min
May 20, 12:48 PM PDT	Severe Thunderstorm Warning	STO	Sacramento	27 min
May 20, 1:26 PM PDT	Tornado Warning	STO	Amador, Sacramento, San Joaquin	34 min
May 20, 1:27 PM PDT	Tornado Warning	STO	Sutter, Yuba	48 min
May 20, 2:03 PM PDT	Severe Thunderstorm Warning	STO	Sacramento, San Joaquin	42 min
May 20, 2:09 PM PDT	Severe Thunderstorm Warning	STO	Amador	36 min
May 20, 2:32 PM PDT	Tornado Warning	STO	Sacramento, Sutter, Yolo	28 min
May 20, 3:00 PM PDT	Severe Thunderstorm Warning	STO	Amador, Calaveras	45 min
May 20, 3:10 PM PDT	Severe Thunderstorm Warning	STO	Placer, Sutter	35 min

Nearby

Severe Thunderstorm Warnings in California, 2002 Every severe thunderstorm warning in 2002

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.