Alert archive / Oregon / Winter Storm Warnings in 2021

Winter Storm Warning 5, NWS Pendleton, OR

December 10, 2021Columbia County, Walla Walla County, Washington; 6 counties in Oregon

NWS Pendleton, OR issued this winter storm warning at Dec 10, 2021, 10:03 AM PST for Columbia County, Walla Walla County, Washington; 6 counties in Oregon. It took effect at Dec 10, 2021, 6:00 PM PST. It was in force for 34 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 10, 2021, 10:03 AM PST (18:03 UTC)
In effect from
Dec 10, 2021, 6:00 PM PST
Expired
Dec 12, 2021, 4:00 AM PST
In force
34 hr
Issued by
NWS Pendleton, OR

Counties Deschutes County, OR, Jefferson County, OR, Umatilla County, OR, Union County, OR, Wallowa County, OR, Wasco County, OR, Columbia County, WA, Walla Walla County, WA

The radar

The Pendleton radar (KPDT), 49 km from the middle of the area, began a volume at 18:03 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.

The nearest sounding before it

Salem/Mcnary, OR (KSLE), launched 12:00Z, 6.1 hours before the alert went out and 299 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, Salem/Mcnary, OR at 12:00Z on 2021-12-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Salem/Mcnary, OR at 12:00Z on 2021-12-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 182 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
649 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
182 m²/s²
0-3 km storm-relative helicity
260 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

936 
WWUS46 KPDT 101803
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
1003 AM PST Fri Dec 10 2021

ORZ502-WAZ030-110700-
/O.EXP.KPDT.WW.Y.0025.000000T0000Z-211210T1800Z/
/O.UPG.KPDT.WS.A.0004.211211T1500Z-211213T0000Z/
/O.NEW.KPDT.WS.W.0005.211211T0600Z-211212T1200Z/
Northern Blue Mountains of Oregon-Northwest Blue Mountains-
Including the cities of Meacham, Tollgate, 
and Ski Bluewood Resort
1003 AM PST Fri Dec 10 2021

...WINTER STORM WARNING IN EFFECT FROM 10 PM THIS EVENING TO 4 AM
PST SUNDAY ABOVE 3500 FEET...
...WINTER WEATHER ADVISORY HAS EXPIRED...

* WHAT...Heavy snow expected above 3500 feet. Total snow
  accumulations of 9 to 16 inches. Winds gusting as high as 35 
  mph.

* WHERE...In Washington, Northwest Blue Mountains. In Oregon, 
  Northern Blue Mountains of Oregon.

* WHEN...From 10 PM this evening to 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. The
  hazardous conditions could impact the evening commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WAZ520-110700-
/O.UPG.KPDT.WS.A.0004.211211T0000Z-211213T0000Z/
/O.NEW.KPDT.WS.W.0005.211211T0200Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
1003 AM PST Fri Dec 10 2021

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 4 AM
PST SUNDAY ABOVE 2500 FEET...

* WHAT...Heavy snow expected above 2500 feet. Total snow
  accumulations of 12 to 24 inches. Winds gusting as high as 45 
  mph.

* WHERE...East Slopes of the Washington Cascades.

* WHEN...From 6 PM this evening to 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. The
  hazardous conditions could impact the evening commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ509-110700-
/O.UPG.KPDT.WS.A.0004.211211T1500Z-211213T0000Z/
/O.NEW.KPDT.WS.W.0005.211211T0600Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
1003 AM PST Fri Dec 10 2021

...WINTER STORM WARNING IN EFFECT FROM 10 PM THIS EVENING TO 4 AM
PST SUNDAY ABOVE 4000 FEET...

* WHAT...Heavy snow expected above 4000 feet. Total snow
  accumulations of 10 to 21 inches. Winds gusting as high as 45 
  mph.

* WHERE...East Slopes of the Oregon Cascades.

* WHEN...From 10 PM this evening to 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
5 follow-up statements
625 
WWUS46 KPDT 110646
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
1046 PM PST Fri Dec 10 2021

WAZ520-111500-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
1046 PM PST Fri Dec 10 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 2500 FEET...

* WHAT...Heavy snow above 2500 feet. Total snow accumulations of
  12 to 24 inches. Winds gusting as high as 45 mph.

* WHERE...East Slopes of the Washington Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ502-WAZ030-111500-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
Northern Blue Mountains of Oregon-Northwest Blue Mountains-
Including the cities of Meacham, Tollgate, 
and Ski Bluewood Resort
1046 PM PST Fri Dec 10 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 3500 FEET...

* WHAT...Heavy snow above 3500 feet. Total snow accumulations of 9
  to 16 inches. Winds gusting as high as 45 mph.

* WHERE...In Washington, Northwest Blue Mountains. In Oregon, 
  Northern Blue Mountains of Oregon.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ509-111500-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
1046 PM PST Fri Dec 10 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 4000 FEET...

* WHAT...Heavy snow above 4000 feet. Total snow accumulations of
  10 to 20 inches. Winds gusting as high as 45 mph.

* WHERE...East Slopes of the Oregon Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
207 
WWUS46 KPDT 111146
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
346 AM PST Sat Dec 11 2021

WAZ520-112300-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
346 AM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 2500 FEET...

* WHAT...Heavy snow above 2500 feet. Total snow accumulations of 
  12 to 24 inches. Winds gusting as high as 45 mph.

* WHERE...East Slopes of the Washington Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ502-WAZ030-112300-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
Northern Blue Mountains of Oregon-Northwest Blue Mountains-
Including the cities of Meacham, Tollgate, 
and Ski Bluewood Resort
346 AM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 3500 FEET...

* WHAT...Heavy snow above 3500 feet. Total snow accumulations of 
  9 to 16 inches. Winds gusting as high as 45 mph.

* WHERE...In Washington, Northwest Blue Mountains. In Oregon, 
  Northern Blue Mountains of Oregon.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ509-112300-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
346 AM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 4000 FEET...

* WHAT...Heavy snow above 4000 feet. Total snow accumulations of 
  10 to 20 inches. Winds gusting as high as 45 mph.

* WHERE...East Slopes of the Oregon Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
440 
WWUS46 KPDT 112246
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
246 PM PST Sat Dec 11 2021

WAZ520-120800-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
246 PM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 2500 FEET...

* WHAT...Heavy snow above 2500 feet. Additional snow 
  accumulations of 8 to 14 inches. Winds gusting as high as 35 
  mph.

* WHERE...East Slopes of the Washington Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ502-WAZ030-120800-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
Northern Blue Mountains of Oregon-Northwest Blue Mountains-
Including the cities of Meacham, Tollgate, 
and Ski Bluewood Resort
246 PM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 3500 FEET...

* WHAT...Heavy snow above 3500 feet. Additional snow accumulations
  of 8 to 14 inches. Winds gusting as high as 25 mph.

* WHERE...In Washington, Northwest Blue Mountains. In Oregon, 
  Northern Blue Mountains of Oregon.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ509-120800-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
246 PM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 4000 FEET...

* WHAT...Heavy snow above 4000 feet. Additional snow accumulations
  of 8 to 16 inches. Winds gusting as high as 30 mph.

* WHERE...East Slopes of the Oregon Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult to impossible. Gusty 
  winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
995 
WWUS46 KPDT 120338
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
738 PM PST Sat Dec 11 2021

ORZ502-WAZ030-120445-
/O.CAN.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
Northern Blue Mountains of Oregon-Northwest Blue Mountains-
738 PM PST Sat Dec 11 2021

...WINTER STORM WARNING IS CANCELLED...

There could be some additional snowfall overnight of around 2 to 
4 inches but heavy snowfall is no longer expected.

$$

WAZ520-121200-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
738 PM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 2500 FEET...

* WHAT...Heavy snow above 2500 feet. Additional snow accumulations
  of up to 5 inches mainly along the Cascade crest with lighter
  amounts along the east slopes.

* WHERE...East Slopes of the Washington Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Plan on slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

ORZ509-121200-
/O.CON.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
738 PM PST Sat Dec 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY
ABOVE 4000 FEET...

* WHAT...Heavy snow above 4000 feet. Additional snow accumulations
  of 4 to 8 inches mainly along the Cascade crest with lighter
  amounts along the east slopes.

* WHERE...East Slopes of the Oregon Cascades.

* WHEN...Until 4 AM PST Sunday.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
605 
WWUS46 KPDT 121145
WSWPDT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Pendleton OR
345 AM PST Sun Dec 12 2021

WAZ520-121245-
/O.EXP.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Washington Cascades-
Including the city of Cliffdell
345 AM PST Sun Dec 12 2021

...WINTER STORM WARNING WILL EXPIRE AT 4 AM PST EARLY THIS
MORNING ABOVE 2500 FEET...

The heaviest snowfall has moved out of the area this morning, 
however another few inches of snowfall are possible along the 
crests today as several lighter bands move across.

$$

ORZ509-121245-
/O.EXP.KPDT.WS.W.0005.000000T0000Z-211212T1200Z/
East Slopes of the Oregon Cascades-
Including the cities of La Pine and Sunriver
345 AM PST Sun Dec 12 2021

...WINTER STORM WARNING WILL EXPIRE AT 4 AM PST EARLY THIS
MORNING ABOVE 4000 FEET...

The heaviest snowfall has moved out of the area this morning, 
however another few inches of snowfall are possible along the 
crests today as several lighter bands move across.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 10, 2:08 PM PSTWind AdvisoryPDTBenton, Columbia, Franklin, Klickitat, Walla Walla, Yakima26 hr

Nearby

Winter Storm Warnings in Oregon, 2021Winter Storm Warnings in Washington, 2021Every winter storm warning in 2021

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.