Alert archive / California / Mesoscale Discussions in 2003

Mesoscale Discussion 358

April 1, 20034 counties in California

The Storm Prediction Center issued this mesoscale discussion at Apr 1, 2003, 3:34 PM PST for 4 counties in California. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
Apr 1, 2003, 3:34 PM PST (23:34 UTC)
Expired
Apr 1, 2003, 5:30 PM PST
In force
116 min
Issued by
the Storm Prediction Center

Counties Butte County, CA, Glenn County, CA, Shasta County, CA, Tehama County, CA

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 12:00Z, 11.6 hours before the alert went out and 230 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 12:00Z on 2003-04-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 12:00Z on 2003-04-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.1939587897117136Sfc1 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
1 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
993 m above ground
0-6 km bulk shear
74 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
29 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.

711 
ACUS11 KWNS 012335
SWOMCD
SPC MCD 012334 
CAZ000-020130-

MESOSCALE DISCUSSION 0358
NWS STORM PREDICTION CENTER NORMAN OK
0534 PM CST TUE APR 01 2003

AREAS AFFECTED...NRN CA

CONCERNING...CONVECTIVE TRENDS 

VALID 012334Z - 020130Z

AN ISOLATED SEVERE STORM WITH LARGE HAIL IS POSSIBLE THROUGH
EARLY EVENING FROM THE SHASTA/SISKIYOUS INTO THE REDDING/RED
BLUFF AREAS .  



A COUPLE OF STRONG THUNDERSTORMS HAVE DEVELOPED DURING THE PAST
COUPLE OF HOURS IN RESPONSE TO DESTABILIZATION ASSOCIATED WITH
DAYTIME HEATING AND LOW-LEVEL UPSLOPE FLOW IN THE UPPER
SACRAMENTO VALLEY.  LARGE-SCALE FORCING FOR UPWARD VERTICAL
MOTION AHEAD OF APPROACHING UPPER TROUGH AXIS MAY BE ENHANCING
ACTIVITY...AND THIS FORCING IS LIKELY TO BE PRESENT THROUGH MUCH
OF THE EVENING HOURS.  HOWEVER...THUNDERSTORMS APPEAR LIKELY TO
WEAKEN/DIMINISH BEYOND THE 02/02-03Z TIME FRAME...DUE TO
STABILIZATION AND WEAKENING LOW-LEVEL FORCING ASSOCIATED WITH
ONSET OF RADIATIONAL COOLING.

UNTIL THEN...VERTICAL SHEAR PROFILES ASSOCIATED WITH VEERING
FIELDS WITH HEIGHT IN LOWER LEVELS...BENEATH STRONG MID/UPPER
JET...MAY BE SUFFICIENT FOR LARGE HAIL...GIVEN FAVORABLE
THERMODYNAMIC ENVIRONMENT WITH CAPE OF 500 TO 1000 J/KG AND LOW
WET BULB/FREEZING LEVELS.

..KERR.. 04/01/2003

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...REV...MFR...STO...EKA...

40772288 41202227 40862128 40252121 39612152 39252256
40072298

Nearby

Mesoscale Discussions in California, 2003Every mesoscale discussion 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.