Alert archive / Oregon / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 7, NWS Pendleton, OR

July 7, 2002Jefferson County, Wasco County, Oregon

NWS Pendleton, OR issued this severe thunderstorm warning at Jul 7, 2002, 6:03 PM PDT for Jefferson County, Wasco County, Oregon. It was in force for 27 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 7, 2002, 6:03 PM PDT (01:03 UTC)
Expired: Jul 7, 2002, 6:30 PM PDT
In force: 27 min
Issued by: NWS Pendleton, OR
Area: Counties, with a storm outline in the text

Counties Jefferson County, OR, Wasco County, OR

The radar

The Pendleton radar (KPDT), 182 km from the middle of the area, began a volume at 01:06 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.

What was reported inside it

Time	Report	Where	Remark
Jul 7, 6:05 PM PDT	Hail 1	Ashwood, OR

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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

Salem/Mcnary, OR (KSLE), launched 00:00Z, 1.1 hours before the alert went out and 175 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: 1220 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: -5 m²/s²
0-3 km storm-relative helicity: 57 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.

256 
WUUS56 KPDT 080103
SVRPDT
ORC031-065-080130-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PENDLETON OR
558 PM PDT SUN JUL 7 2002

THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WARNING HAS BEEN EXTENDED FOR CENTRAL EASTERN JEFFERSON COUNTY IN  
  CENTRAL OREGON
  A NEW WARNING FOR SOUTHEASTERN WASCO COUNTY IN NORTH CENTRAL OREGON

* UNTIL 630 PM PDT

* AT 558 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 8 MILES SOUTH OF ASHWOOD...MOVING NORTH AT 35
  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ANTELOPE AT 620 PM PDT
  SHANIKO AT 625 PM PDT

* THE MAIN THREAT WITH THIS STORM IS LARGE HAIL.

LAT...LON 4466 12092 4454 12075 4498 12052 4504 12081

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 Pendleton, OR wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 7, 2:35 PM PDT, 3 hours 28 minutes earlier.

Area forecast discussion, Jul 7, 2:35 PM PDT, 3 hours 28 minutes before

NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
235 PM PDT SUN JUL 7 2002

A LOW PRESSURE SYSTEM HAS MOVED ONSHORE...AND STARTING TO CROSS OVER
TO THE EAST SIDE OF THE CASCADES. CONVECTIVE SHOWERS ARE FORMING
ALONG THE EAST SLOPES OF THE CASCADES...SOUTH OF MADRAS AND NORTH
OF JOHN DAY EXTENDING INTO THE BLUE MOUNTAINS AS SEEN ON SATELLITE
IMAGERY AND RADAR. THIS SYSTEM IS VERY UNSTABLE AND MOIST...AND THE
SHOWER AND THUNDERSTORM ACTIVITY WILL LAST THROUGH TONIGHT. SOME OF
THESE THUNDERSTORMS ALSO HAVE THE POTENTIAL OF BECOMING SEVERE WITH
HIGH WINDS...HEAVY RAINS AND HAIL. SOME SHOWERS MAY LINGER INTO THE
THE EARLY MORNING HOURS. HOWEVER...DRY AND COOLER TEMPERATURES WILL
FOLLOW TOMORROW AS A RIDGE BEGINS TO BUILD INTO THE PACIFIC
NORTHWEST ON MONDAY. BY TUESDAY...THE TEMPERATURE WILL START TO WARM
AGAIN. PALMER

EXTENDED...A RIDGE WILL BE OVER THE AREA THROUGH THURSDAY PROVIDING
SUNNY SKIES AND INCREASING TEMPERATURES. AS THE RIDGE SHIFTS EAST ON
THURSDAY EVENING AND FRIDAY MOISTURE WILL MIGRATE NORTHWARD IN THE
THE AREA AROUND THE EDGE OF THE RIDGE. THIS MOISTURE AND THE
RECEDING RIDGE WILL INCREASE THE INSTABILITY OVER CENTRAL OREGON...
THE OCHOCOS AND THE BLUE MOUNTAINS. SOME AFTERNOON AND EVENING
THUNDERSTORMS MAY DEVELOP. THE REST OF THE AREA WILL REMAIN HOT AND
DRY. BY SATURDAY THE 850 MB TEMPERATURES AND VARIOUS THICKNESS
VALUES WILL DECREASE SLIGHTLY SUGGESTING THAT TEMPERATURES WILL DROP
SLIGHTLY.  COONFIELD

PDT 3200  ALW 3200  PSC 3000  YKM 3000

KPDT...VCP32/CSR21...OPERATIONAL.

.KPDT...NONE

The office that day

Everything else NWS Pendleton, OR issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 7, 5:04 PM PDT	Severe Thunderstorm Warning	PDT	Union	56 min
Jul 7, 5:27 PM PDT	Severe Thunderstorm Warning	PDT	Crook, Jefferson	33 min
Jul 7, 6:02 PM PDT	Severe Thunderstorm Warning	PDT	Umatilla, Union	43 min
Jul 7, 6:28 PM PDT	Severe Thunderstorm Warning	PDT	Gilliam, Sherman	47 min
Jul 7, 6:31 PM PDT	Severe Thunderstorm Warning	PDT	Umatilla, Union	44 min
Jul 7, 8:52 PM PDT	Severe Thunderstorm Warning	PDT	Morrow	28 min
Jul 7, 10:08 PM PDT	Severe Thunderstorm Warning	PDT	Union	52 min
Jul 7, 10:44 PM PDT	Severe Thunderstorm Warning	PDT	Union	46 min
Jul 7, 11:21 PM PDT	Severe Thunderstorm Warning	PDT	Wallowa	69 min
Jul 8, 1:52 AM PDT	Severe Thunderstorm Warning	PDT	Wallowa	23 min
Jul 8, 2:16 AM PDT	Severe Thunderstorm Warning	PDT	Wallowa	44 min

Nearby

Severe Thunderstorm Warnings in Oregon, 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.