Washington, 2006

Debris Flow in Washington, July 4, 2006

July 4, 2006 · NWS PDT · 1 event in 1 county or zone

Highway 410 closed at MP 88 due to mud and rock slide during heavy rainfall. US Highway 12 closed due to rock slide near Rimrock Lake.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PDT wrote it up.

Highway 410 closed at MP 88 due to mud and rock slide during heavy rainfall. US Highway 12 closed due to rock slide near Rimrock Lake. A vehicle was struck by rocks during the slide at Rimrock Lake.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jul 4, 2:15 PM PST, 3 hours 30 minutes earlier.

Area forecast discussion, Jul 4, 2:15 PM PST, 3 hours 30 minutes before
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
315 PM PDT TUE JUL 4 2006

UPDATED AVIATION DISCUSSION

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...WATER VAPOR IMAGERY
SHOWS THE NEXT IN A SERIES OF WAVES MOVING ONSHORE THE NORTHERN
CALIFORNIA/SOUTHWEST OREGON COAST. AHEAD OF THIS FEATURE...SURFACE
HEATING ALONG WITH A UNSTABLE ATMOSPHERE IS RESULTING IN THE
DEVELOPMENT OF CUMULUS BUILDUPS ACROSS MUCH OF CENTRAL OREGON...AND
ACROSS THE EAST CASCADE SLOPES...WITH RADAR SHOWING THUNDERSTORMS
DEVELOPING ALONG THE CENTRAL CASCADES OF WASHINGTON. FROM THE BLUES
EAST...CUMULUS DEVELOPMENT IS LESS FURTHER AWAY FROM THE LIFT
AHEAD OF THE WAVE.

THE AFOREMENTIONED WAVE WILL CROSS CENTRAL OREGON THIS EVENING...
EXITING CENTRAL WASHINGTON DURING THE OVERNIGHT HOURS. ISOLATED
TO SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP LATE THIS
AFTN/EVENING...WITH THE GREATEST COVERAGE ACROSS THE EASTERN OR
MTNS AND THE EAST CASCADE SLOPES. WILL RETAIN ISOLATED TSTMS INTO
THE OVERNIGHT HOURS ACROSS CENTRAL WA/EXTREME NORTHERN OREGON
WITH RESIDUAL INSTABILITY IN THE MIDDLE LEVELS OF THE
ATMOSPHERE.

MORE STABLE MARINE AIR WILL GRADUALLY WORK ACROSS THE REGION
WED/THU...WITH TEMPERATURES COOLING TO JUST ABOVE AVERAGE ACROSS
CENTRAL WA/OR ON WEDNESDAY...AND ACROSS EASTERN WA/OR BY THURSDAY.
TSTM COVERAGE WILL DECREASE AS WELL WITH THE MORE STABLE AIR
MASS...WITH MOST OF THE ACTIVITY CONFINED TO CENTRAL AND NORTHEAST
OREGON WED/THU AFTN.

.LONG TERM...FRIDAY THROUGH TUESDAY...SOME UNCERTAINTY REMAINS IN
MID RANGE AS TO STRENGTH OF UPPER RIDGE VERSUS AMOUNT OF BREAK DOWN
EXPECTED. SOME GENERAL CONSENSUS THAT THE RIDGE WILL BE FLAT BY
FRIDAY THEN TRY TO BUILD NORTHWEST SATURDAY AND SUNDAY. MODELS TRY
TO INDICATE A STRONGER TROUGH MOVING TO THE PACNW COAST EARLY NEXT
WEEK THOUGH DEPTH AND DEGREE TO WHICH IT MOVES EAST IS UP FOR
DEBATE. OVERALL EXPECT UPPER LEVEL FLOW TO BE WEST-SOUTHWEST TO WEST
OVER THE PACNW. THIS WOULD LEAD TO GENERALLY DRY CONDITIONS WITH
TEMPS AT OR SLIGHTLY ABOVE SEASONAL. IF THE UPPER RIDGE DOES REBUILD
SOME ON THE WEEKEND...THIS COULD OPEN PORTIONS OF EASTERN OREGON TO
A FEW AFTERNOON/EVENING THUNDERSTORMS AS DISTURBANCES MOVING THROUGH
IDAHO CLIP THE REGION. FOR NOW WILL BE CONSERVATIVE AND ONLY HINT A
FEW STORMS OVER THE WALLOWA...ELKHORN AND STRAWBERRY MOUNTAINS.

&&

.AVIATION...VFR CONDITIONS CAN BE EXPECTED DURING THE NEXT 24 HOURS.
ISOLATED THUNDERSTORMS MAY CREATE BRIEF MVFR CONDITIONS WITH LOWERED
CEILINGS AND VISIBILITIES DUE TO HEAVY RAIN SHOWERS. ALSO GUSTY
WINDS WILL BE POSSIBLE WITH THESE THUNDERSTORMS. TIMING OF
THUNDERSTORMS FOR THE TAFS CONTINUES TO BE UNCERTAIN AT THIS TIME
BUT WILL HEDGE TOWARDS AN EVENING OCCURRENCE AT KPDT...KALW AND
KPSC. CLOUDS DEVELOPING SOUTH OF KYKM COULD BRING A SHOWER OR STORM
TO KYKM BEFORE 4/2300Z. MEANWHILE DEVELOPMENT OF CUMULUS DOWNSTREAM
OF KRDM AND KDLS CONTINUES TO BE STRONGLY CAPPED AT THIS TIME...AND
A LATER START (IF IT HAPPENS AT ALL) IS EXPECTED. STORMS MAY PERSIST
INTO THE EARLY PORTION OF THE OVERNIGHT PERIOD. BUT DOWNSTREAM
DISTURBANCES ARE WEAKER AND NOT AS ORGANIZED AS THE DURING THE
PREVIOUS NIGHT...AND EXPECT MOST ACTIVITY TO GRADUALLY END BY EARLY
MORNING WEDNESDAY. 90

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  65  93  61  87 /  20  10  20  10
ALW  70  92  64  89 /  20  10  20  10
PSC  68  97  62  91 /  20  10  10  10
YKM  65  90  58  87 /  20  10  10  10
HRI  68  93  62  89 /  20  10  10  10
ELN  65  88  57  85 /  20  10  10  10
RDM  52  82  48  80 /  30  10  20  10
LGD  61  87  58  84 /  20  20  20  20
5J0  55  91  54  87 /  20  20  20  10
DLS  65  82  61  80 /  20  10  10  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HEAT ADVISORY UNTIL 7 PM PDT THIS EVENING FOR ORZ044-ORZ501.
WA...HEAT ADVISORY UNTIL 7 PM PDT THIS EVENING FOR WAZ028-WAZ029.

&&

TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
89/90/90
Hazardous weather outlook, Jul 4, 5:30 PM PST, 15 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
630 PM PDT TUE JUL 4 2006

...UPDATED FOR SEVERE THUNDERSTORM WATCH BOX FOR NORTHEAST OREGON
AND SOUTHEAST WASHINGTON IN EFFECT UNTIL 1000 PM PDT THIS EVENING...

WAZ024-501-502-026>030-ORZ041>044-049-050-501>506-051215-
EAST SLOPES OF THE CENTRAL CASCADES OF WASHINGTON-
EAST SLOPES OF THE SOUTHERN CASCADES OF WASHINGTON-
KITTITAS VALLEY-YAKIMA VALLEY-LOWER COLUMBIA BASIN OF WASHINGTON-
FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON-
NORTHWEST BLUE MOUNTAINS-EASTERN COLUMBIA RIVER GORGE OF OREGON-
NORTH CENTRAL OREGON-CENTRAL OREGON-
LOWER COLUMBIA BASIN OF OREGON-GRANDE RONDE VALLEY-WALLOWA COUNTY-
FOOTHILLS OF THE BLUE MOUNTAINS OF OREGON-
NORTHERN BLUE MOUNTAINS OF OREGON-
SOUTHERN BLUE MOUNTAINS OF OREGON-
NORTHERN WHEELER AND SOUTHERN GILLIAM COUNTIES-JOHN DAY BASIN-
OCHOCO-JOHN DAY HIGHLANDS-
630 PM PDT TUE JUL 4 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL AND NORTHEAST OREGON
AS WELL AS SOUTH CENTRAL AND SOUTHEAST WASHINGTON.

.DAY ONE...TONIGHT

SLIGHT RISK OF SEVERE THUNDERSTORMS UNTIL 10 PM PDT
     LOWER COLUMBIA BASIN OF WASHINGTON, LOWER COLUMBIA BASIN OF
     WASHINGTON, FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON,
     NORTHWEST BLUE MOUNTAINS, LOWER COLUMBIA BASIN OF OREGON,
     GRANDE RONDE VALLEY, WALLOWA COUNTY, FOOTHILLS OF THE BLUE
     MOUNTAINS OF OREGON, NORTHERN BLUE MOUNTAINS OF OREGON,
     SOUTHERN BLUE MOUNTAINS OF OREGON

THUNDERSTORMS
     EASTERN COLUMBIA RIVER GORGE OF WASHINGTON, EAST SLOPES OF THE
     CENTRAL CASCADES OF WASHINGTON, EAST SLOPES OF THE SOUTHERN
     CASCADES OF WASHINGTON, KITTITAS VALLEY, YAKIMA VALLEY,
     EASTERN COLUMBIA RIVER GORGE OF OREGON, NORTH CENTRAL OREGON,
     CENTRAL OREGON, SOUTHERN BLUE MOUNTAINS OF OREGON, NORTHERN
     WHEELER AND SOUTHERN GILLIAM COUNTIES, JOHN DAY BASIN,
     OCHOCO-JOHN DAY HIGHLANDS

THE AIRMASS OVER THE COLUMBIA BASIN AND NORTHEAST OREGON IS VERY
WARM AND UNSTABLE. A DISTURBANCE CROSSING OREGON AND SOUTHEAST
WASHINGTON THIS EVENING WILL RELEASE THIS ENERGY AND TRIGGER
THUNDERSTORMS. A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 10 PM
PDT THIS EVENING FOR THE FOLLOWING COUNTIES IN NORTHEAST OREGON...
UMATILLA...UNION...WALLOWA AND THE FOLLOWING COUNTIES IN SOUTHEAST
WASHINGTON...WALLA WALLA...COLUMBIA. SOME THUNDERSTORMS IN THE WATCH
AREA ARE CAPABLE OF PRODUCING LARGE HAIL AND STRONG DAMAGING WINDS.
OTHERWISE...AN UNSTABLE ATMOSPHERE WILL LEAD TO SCATTERED SHOWERS
AND THUNDERSTORMS THIS EVENING AND OVERNIGHT ACROSS INTERIOR
WASHINGTON AND OREGON.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THUNDERSTORMS WEDNESDAY
     FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON, NORTHWEST BLUE
     MOUNTAINS, NORTH CENTRAL OREGON, CENTRAL OREGON, GRANDE RONDE
     VALLEY, WALLOWA COUNTY, FOOTHILLS OF THE BLUE MOUNTAINS OF
     OREGON, NORTHERN BLUE MOUNTAINS OF OREGON, SOUTHERN BLUE
     MOUNTAINS OF OREGON, NORTHERN WHEELER AND SOUTHERN GILLIAM
     COUNTIES, JOHN DAY BASIN, OCHOCO-JOHN DAY HIGHLANDS

MARINE AIR WILL MOVE INTO THE LOWER COLUMBIA BASIN TONIGHT. THIS
WILL END THE EXCESSIVE HEAT AND ALLOW TEMPERATURES TO DECREASE OVER
THE AREA WEDNESDAY.

THE COMBINATION OF SURFACE HEATING AND LOW TO MID LEVEL
MOISTURE IN AN UNSTABLE ATMOSPHERE WILL CONTINUE TO LEAD TO
ANOTHER ROUND OF AFTERNOON AND EVENING THUNDERSTORMS WEDNESDAY...
WITH THE GREATEST THREAT ACROSS NORTHEAST OREGON. A FEW STORMS
COULD BECOME STRONG WITH SMALL HAIL AND STRONG GUSTY WINDS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THIS EVENING FOR SEVERE THUNDERSTORMS
IN NORTHEAST OREGON AND SOUTHEAST WASHINGTON. SPOTTER ACTIVATION MAY
BE REQUIRED ELSEWHERE THIS EVENING FOR THUNDERSTORMS.

SPOTTER ACTIVATION MAY BE REQUIRED ON WEDNESDAY FOR THUNDERSTORMS.

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

GRAPHICAL FORECASTS OF WEATHER HAZARDS OUT TO SEVEN DAYS
ARE DISPLAYED ON THE WORLD WIDE WEB AT:

WWW.WRH.NOAA.GOV/PENDLETON/CURRENTHAZARDS/HWO.HTML

ALL LETTERS IN THE ABOVE URL ARE LOWER CASE...EXCEPT THE H IN
CURRENTHAZARDS.

In the hours before

Local storm report, Jul 4, 5:33 PM PST, 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
633 PM PDT TUE JUL 04 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0505 PM     HAIL             5 WNW CLE ELUM          47.22N 121.03W
07/04/2006  E0.75 INCH       KITTITAS           WA   PUBLIC

            3/4 INCH HAIL FELL AND COVERED THE GROUND. YAKIMA RIVER
            HAS RISEN 6 TO 8 INCHES.

0520 PM     HAIL             1 ESE COVE              45.29N 117.79W
07/04/2006  E1.00 INCH       UNION              OR   TRAINED SPOTTER

            SPOTTER CALLED FROM ELGIN TO REPORT QUARTER SIZED
            HAIL...HEAVY RAIN AND GUSTY WINDS BLOWING DOWN TREE
            BRANCHES.

0522 PM     HAIL             N ELGIN                 45.57N 117.92W
07/04/2006  E1.00 INCH       UNION              OR   TRAINED SPOTTER

            QUARTER SIZED HAIL COVERED MOST OF GROUND. HEAVY RAIN HAD
            FALLEN FOR 15 MINUTES AND WAS CONTINUING AS OF TIME OF
            REPORT. STRONG WINDS OCCURRING TOO.

&&

PERRY

Event by event

1 debris flow. Local standard time, as filed.

Debris Flow, East Slopes of the Central Cascades

When
July 4, 5:45 PM PST
Where
East Slopes of the Central Cascades forecast zone
Reported by
TRAINED SPOTTER

What these are

Debris Flow
A fast-moving slurry of mud, rock and debris, usually on a slope soaked by heavy rain or stripped by a fire.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Washington in 2006Every state in 2006This day in weather historyWarnings in Washington, July 2006

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5526190.