Alert archive / California / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 15, NWS Reno, NV

July 17, 2002Lassen County, Plumas County, California

NWS Reno, NV issued this severe thunderstorm warning at Jul 17, 2002, 1:53 PM PDT for Lassen County, Plumas 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 outline as issued.

The facts

Issued: Jul 17, 2002, 1:53 PM PDT (20:53 UTC)
Expired: Jul 17, 2002, 2:15 PM PDT
In force: 22 min
Issued by: NWS Reno, NV
Area: Counties, with a storm outline in the text

Counties Lassen County, CA, Plumas County, CA

The radar

The Reno radar (KRGX), 64 km from the middle of the area, began a volume at 20:56 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Reno, NV (KREV), launched 12:00Z, 8.9 hours before the alert went out and 174 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2800 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 64 m²/s²
0-3 km storm-relative helicity: 94 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.

030 
WUUS55 KREV 172053
SVRREV
CAC035-063-172115-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE RENO NV
152 PM PDT WED JUL 17 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME SOUTHEASTERN LASSEN COUNTY IN NORTHERN CALIFORNIA
  THIS INCLUDES THE CITY OF DOYLE
  EAST CENTRAL PLUMAS COUNTY IN NORTHERN CALIFORNIA
  THIS INCLUDES THE CITY OF CHILCOOT

* UNTIL 215 PM PDT

* AT 151 PM PDT...AMATEUR RADIO WEATHER SPOTTERS REPORTED A SEVERE
  THUNDERSTORM OVER VINTON...OR ABOUT 2 MILES NORTHWEST OF
  CHILCOOT...MOVING NORTH AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  2 MILES SOUTHEAST OF FRENCHMAN LAKE AT 215 PM PDT

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER
AWAY FROM CREEK BEDS AND OTHER FLOOD-PRONE AREAS. REMEMBER...A SEVERE
THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...DAMAGING WINDS IN
EXCESS OF 55 MPH...DEADLY LIGHTNING...AND VERY HEAVY RAIN.

HAIL OVER THREE QUARTERS OF AN INCH IN DIAMETER HAS BEEN REPORTED 
WITH THIS STORM. IF YOU ARE IN THE PATH OF THE STORM...PUT YOUR CAR 
IN A GARAGE AND MOVE TO A SUBSTANTIAL SHELTER.

LAT...LON 3973 12028 3974 12005 4004 12004 4002 12033

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 Reno, NV wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 17, 9:45 AM PDT, 4 hours 8 minutes earlier.

Area forecast discussion, Jul 17, 9:45 AM PDT, 4 hours 8 minutes before

WESTERN NEVADA AND EASTERN CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
945 AM PDT WED JUL 17 2002

WEAK UPPER LOW AND VORT MAX OFF CENTRAL CA CST NEAR SFO BAY AREA
NOTED ON WATER VAPOR LOOP. THIS FEATURE FORECAST TO MOVE SLOWLY ENE
NEXT 36 HOURS MOVING OVER WRN NV THU AFTN. MORNING SOUNDING AT REV
A LITTLE MORE MOIST AND UNSTABLE WITH PRECIP WATER NEAR THREE QUARTERS
OF AN INCH. TRIGGER TEMP FOR CONVECTION AROUND 81 DEG F AT 17Z WITH
VIS LOOP SHOWING RAPID GROWTH OF CU ALONG MTNS. BEST FOCUSING FOR
STRONGER TSTMS OVER  MINERAL COUNTY WHERE CONVERGENCE/DIVERGENCE
COUPLET FORECAST. WITH 15KT WINDS AT 700 MB CELL MOVEMENT SHOULD
BE FAST ENOUGH KEEP FF POTENTIAL IN MODERATE RANGE. THETA-E RIDGE OVER
E CENTRAL NV WITH NEG THETA-E ADVECTION FROM APPROACHING TROUGH.
MICROBURST POTENTIAL ALSO MODERATE WITH LOWER CCL AND TEMPS DUE TO
INCREASING CLOUDS AND MOISTURE. BETTER POTENTIAL FOR STRONGER AND
WETTER TSTMS ON THURSDAY AS VORT MAX MOVES OVER AREA AND MOISTURE
VALUES UP FROM TODAY CONVECTION. NO UPDATES. CYLKE

.REV...NONE.

The office that day

Everything else NWS Reno, NV issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 2:03 PM PDT	Severe Thunderstorm Warning	REV	Nevada, Placer, Sierra	42 min
Jul 17, 2:37 PM PDT	Severe Thunderstorm Warning	REV	Lassen, Plumas	33 min
Jul 17, 3:01 PM PDT	Severe Thunderstorm Warning	REV	Lassen, Plumas, Sierra	29 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; radar from the NEXRAD Level II archive.