Alert archive / California / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 438

May 29, 20037 counties in California; Washoe County, Nevada; 4 counties in Oregon

The Storm Prediction Center issued this severe thunderstorm watch at May 29, 2003, 5:30 PM PDT for 7 counties in California; Washoe County, Nevada; 4 counties in Oregon. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 29, 2003, 5:30 PM PDT (00:30 UTC)
Expired
May 29, 2003, 11:00 PM PDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Humboldt County, CA, Lassen County, CA, Modoc County, CA, Shasta County, CA, Siskiyou County, CA, Tehama County, CA, Trinity County, CA, Washoe County, NV, Harney County, OR, Jackson County, OR, Klamath County, OR, Lake County, OR

Warnings issued inside it

1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 29, 7:02 PM PDTSevere Thunderstorm WarningEKATrinity28 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 0.5 hours before the alert went out and 135 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, Medford/Jackson, OR at 00:00Z on 2003-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 555 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, Medford/Jackson, OR at 00:00Z on 2003-05-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.1939587897Sfc1 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
555 J/kg
Mixed-layer CIN
-226 J/kg
Mixed-layer LCL
2347 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 29, 9:07 PM PDTMesoscale DiscussionSPCLassen, Modoc, Shasta, Siskiyou, Tehama, Trinity53 min
May 30, 3:42 AM PDTMesoscale DiscussionSPCDel Norte, Siskiyou63 min

Nearby

Severe Thunderstorm Watches in California, 2003Severe Thunderstorm Watches in Oregon, 2003Severe Thunderstorm Watches in Nevada, 2003Every severe thunderstorm watch in 2003

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.