Alert archive / Oregon / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 45, NWS Pendleton, OR

August 25, 2002Union County, Oregon

NWS Pendleton, OR issued this severe thunderstorm warning at Aug 25, 2002, 5:03 PM PDT for Union County, Oregon. It was in force for 42 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: Aug 25, 2002, 5:03 PM PDT (00:03 UTC)
Expired: Aug 25, 2002, 5:45 PM PDT
In force: 42 min
Issued by: NWS Pendleton, OR
Area: Counties, with a storm outline in the text

County Union County, OR

The radar

The Pendleton radar (KPDT), 78 km from the middle of the area, began a volume at 00:07 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

Boise Airport, ID (KBOI), launched 00:00Z, 0.1 hours before the alert went out and 239 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: 3474 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: 64 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.

692 
WUUS56 KPDT 260003
SVRPDT
ORC061-260045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PENDLETON OR
502 PM PDT SUN AUG 25 2002

THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL UNION COUNTY IN NORTHEAST OREGON

* UNTIL 545 PM PDT

* AT 502 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER COVE...OR ABOUT 12 MILES EAST OF LA
  GRANDE...MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  RURAL CENTRAL UNION COUNTY AT 520 PM PDT

HAIL TO ONE INCH...DAMAGING WINDS...AND HEAVY RAINFALL ARE LIKELY 
WITH THIS STORM. TAKE COVER IN A STURDY BUILDING UNTIL THE STORM HAS 
PASSED.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY
MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO
RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS.

LAT...LON 4505 11837 4509 11769 4538 11772 4548 11780
          4543 11804 4539 11837

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 Aug 25, 1:25 PM PDT, 3 hours 38 minutes earlier.

Area forecast discussion, Aug 25, 1:25 PM PDT, 3 hours 38 minutes before

NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
125 PM PDT SUN AUG 25 2002

SHORT TERM AND FIRE WEATHER...AN UPPER LEVEL SHORT WAVE WILL MOVE
ACROSS THE FORECAST AREA THIS AFTERNOON AND TONIGHT. DYNAMIC LIFT
AND INSTABILITY ASSOCIATED WITH THE WAVE WILL TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS AS THIS SYSTEM MOVES THROUGH. THE
THUNDERSTORMS THIS AFTERNOON AND TONIGHT WILL BE MOSTLY WET AS THE
AIR MASS OVER THE AREA IS RATHER MOIST. A WEAK MARINE PUSH WILL
BEGIN LATE THIS AFTERNOON ALONG THE EAST SLOPES OF THE CASCADES AND
THEN MOVE ACROSS THE REMAINDER OF THE FORECAST AREA THIS EVENING.
THIS WILL INCREASE WINDS TONIGHT AND USHER IN A MUCH MORE STABLE AIR
MASS FOR MONDAY. THE SHORT WAVE WILL MOVE INTO IDAHO AND MONTANA ON
MONDAY WITH NORTHERLY FLOW ALOFT ON THE BACK SIDE OF THE UPPER
TROUGH OVER THE FORECAST AREA. ON MONDAY MARGINAL INSTABILITY WILL
REMAIN OVER EXTREME NORTHEAST OREGON FOR POSSIBLE ISOLATED
THUNDERSTORMS...MAINLY OVER WALLOWA COUNTY. THE UPPER SHORT WAVE
WILL STALL OVER MONTANA ON MONDAY BEFORE DIGGING SOUTHWEST INTO
IDAHO AND SOUTHEAST OREGON ON TUESDAY. THIS WILL ALLOW SOME WRAP
AROUND MOISTURE TO RETURN TO EXTREME EASTERN OREGON FOR SOME SHOWERS
AND MOSTLY WET ISOLATED THUNDERSTORMS ON TUESDAY. THE AFOREMENTIONED
SHORT WAVE WILL MOVE INTO EASTERN OREGON ON WEDNESDAY FOR A CHANCE
OF MAINLY AFTERNOON AND EVENING SHOWERS AND MOSTLY WET THUNDERSTORMS
OVER THE MOUNTAINS OF NORTHEAST OREGON.  POLAN

IN THE EXTENDED...STUBBORN SHORT WAVE/MID LEVEL LOW PRESSURE OVER
EASTERN OREGON WILL BEGIN TO WEAKEN AND DRIFT INTO IDAHO THURSDAY.
BUT LINGERING MOISTURE REMAINS MAINLY OVER THE EASTERN FORECAST AREA
THAT INCLUDES THE BLUE AND WALLOWA MOUNTAINS...WHICH WILL SEE SOME
AFTERNOON AND EVENING THUNDERSTORMS. ALSO WITH THE EXITING LOW COMES
A LONG WAVE TROUGH ENTERING THE PACIFIC NORTHWEST COAST THURSDAY
AFTERNOON AND SOME ISOLATED THUNDERSTORMS MAY DEVELOP OVER THE
NORTHERN CASCADES NEAR GOLDENDALE LATE THURSDAY AND INTO THE
EVENING. DRIER AIR FILTERS INTO THE CASCADES FRIDAY BUT INSTABILITY
PERSISTS OVER THE WALLOWA AND BLUE MOUNTAINS WHERE ISOLATED
THUNDERSTORMS ARE POSSIBLE. AS THE TROUGH MOVES EAST AND AWAY FROM
THE THE AREA SATURDAY...MUCH DRIER AIR WILL INVADE ALL OF NORTHEAST
OREGON AND SOUTHEAST WASHINGTON AND A RETURN TO MOSTLY SUNNY AND
WARMER TEMPERATURES ARE LIKELY NEXT WEEKEND.

PDT 3000  ALW 3000  PSC 2000  YKM 2000

KPDT...VCP21/PRECIP MODE...OPERATIONAL.

.KPDT...NONE.

In the hours before

Local storm report, Aug 25, 4:25 PM PDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OREGON
425 PM PDT SUN AUG 25 2002

TIME(PDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0423 PM    8 W CULVER                OR   .75 INCH HAIL
08/25/02   JEFFERSON                      7.5 MILES WEST OF
                                          CULVER AT 4:25 P.M.
                                          REPORTED BY STORM
                                          SPOTTER JE-9.

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 25, 5:31 PM PDT	Severe Thunderstorm Warning	PDT	Deschutes	44 min
Aug 25, 5:31 PM PDT	Severe Thunderstorm Warning	PDT	Deschutes	44 min
Aug 25, 5:56 PM PDT	Flash Flood Warning	PDT	Deschutes	2 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.