Alert archive / Washington / Winter Storm Warnings in 2021

Winter Storm Warning 3, NWS Spokane, WA

January 11, 2021Ferry County, Okanogan County, Washington

NWS Spokane, WA issued this winter storm warning at Jan 11, 2021, 2:56 AM PST for Ferry County, Okanogan County, Washington. It took effect at Jan 11, 2021, 1:00 PM PST. It was in force for 23 hr. 13 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jan 11, 2021, 2:56 AM PST (10:56 UTC)
In effect from
Jan 11, 2021, 1:00 PM PST
Expired
Jan 12, 2021, 12:09 PM PST
In force
23 hr
Issued by
NWS Spokane, WA

Counties Ferry County, WA, Okanogan County, WA

The radar

The Spokane radar (KOTX), 145 km from the middle of the area, began a volume at 10:55 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

TimeReportWhereRemark
Jan 12, 7:00 AM PSTSNOW 4.54 W Boyds, WACOCORAHS STATION WA-FY-8 10.2 NW KETTLE FALLS.
Jan 12, 7:00 AM PSTSNOW 4.57 Wsw Malo, WACOCORAHS STATION WA-FY-10 7.6 N REPUBLIC.
Jan 12, 7:00 AM PSTSNOW 4.5Boyds, WA
Jan 12, 7:00 AM PSTSNOW 6.51 Ese Twisp, WACOCORAHS STATION WA-OK-33 TWISP 1.3 ESE.
Jan 12, 7:00 AM PSTSNOW 9.56 Ese Mazama, WACOCORAHS STATION WA-OK-16 6.8 NNW WINTHROP.
Jan 12, 8:00 AM PSTSNOW 57 S Molson, WAELEVATION 3400 FT.
Jan 12, 8:00 AM PSTSNOW 73 Ese Carlton, WAREPORTED AT TEXAS CREEK ROAD CARLTON WA... STILL SNOWING.
Jan 12, 8:00 AM PSTSNOW 81 Nw Winthrop, WAREPORTED AT 24 W CHEWUCH RD, WINTHROP, WA 98862 FROM THE WINTHROP FMO.
Jan 12, 8:30 AM PSTSNOW 42 E Wauconda, WA
Jan 12, 8:30 AM PSTSNOW 101 Wnw Mazama, WA
Jan 12, 8:31 AM PSTSNOW 71 W Twisp, WA
Jan 12, 9:33 AM PSTSNOW 122 Ese Mazama, WAVIA SOCIAL MEDIA.
Jan 12, 10:30 AM PSTHEAVY SNOW 5.53 Nw Malo, WA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 10.9 hours before the alert went out and 222 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, Spokane, WA at 00:00Z on 2021-01-11Temperature 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, Spokane, WA at 00:00Z on 2021-01-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 square meters per square second.193958Sfc1 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
944 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
206 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

432 
WWUS46 KOTX 111056
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
256 AM PST Mon Jan 11 2021

...HEAVY WET SNOW POSSIBLE MONDAY NIGHT AND TUESDAY...

.A very moist storm is likely to bring moderate to heavy
precipitation Monday night into Tuesday. Precipitaiton in the
Okanogan Highlands, Methow Valley, and along the Cascade Crest is
expected to fall as snow before transitioning to rain late
Tuesday. Snow rates could approach 1-2 inches per hour.

WAZ042-112200-
/O.UPG.KOTX.WS.A.0003.210112T0000Z-210113T0000Z/
/O.NEW.KOTX.WS.W.0003.210111T2100Z-210113T0000Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Twisp, Winthrop, 
Stehekin, Conconully, Loup Loup Pass, Stevens Pass, Plain, 
and Holden Village
256 AM PST Mon Jan 11 2021

...WINTER STORM WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO
4 PM PST TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 5 to 10
  inches in the valleys, and 8 to 16 inches in the mountains. 
  Locally up to two feet above 4000 feet.

* WHERE...Mazama, Twisp, Winthrop, Stehekin, Conconully, Loup 
  Loup Pass, Stevens Pass, Plain, and Holden Village.

* WHEN...From 1 PM this afternoon to 4 PM PST Tuesday.

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

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour
  coupled with the weight of the snow could result in tree damage
  and isolated power outages.

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.

&&

$$

WAZ038-112200-
/O.CON.KOTX.WS.A.0003.210112T0600Z-210113T0000Z/
Okanogan Highlands-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
and Sherman Pass
256 AM PST Mon Jan 11 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH
TUESDAY AFTERNOON...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 9 
  inches possible.

* WHERE...Republic, Wauconda, Chesaw Road, Highway 20 Wauconda 
  Summit, Boulder Creek Road, and Sherman Pass.

* WHEN...From Monday evening through Tuesday afternoon.

* IMPACTS...Travel could be very difficult. The hazardous 
  conditions could impact the morning commute.

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
4 follow-up statements
604 
WWUS46 KOTX 112300
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
300 PM PST Mon Jan 11 2021

...HEAVY WET SNOW TONIGHT AND TUESDAY...

.A very moist storm is likely to bring moderate to heavy
precipitation overnight into Tuesday. Precipitaiton in the 
Okanogan Highlands, Methow Valley, and along the Cascade Crest is 
expected to fall as snow before transitioning to rain late 
Tuesday. Snow rates could approach 1-2 inches per hour.

WAZ038-120700-
/O.UPG.KOTX.WS.A.0003.210112T0600Z-210113T0000Z/
/O.EXB.KOTX.WS.W.0003.210112T0600Z-210113T0000Z/
Okanogan Highlands-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
and Sherman Pass
300 PM PST Mon Jan 11 2021

...WINTER STORM WARNING IN EFFECT FROM 10 PM THIS EVENING TO 4 PM
PST TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations 3 to 7
  inches with locally up to a foot in the higher terrain.

* WHERE...Republic, Wauconda, Chesaw Road, Highway 20 Wauconda 
  Summit, Boulder Creek Road, and Sherman Pass.

* WHEN...From 10 PM this evening to 4 PM PST Tuesday.

* IMPACTS...Travel could be very difficult. The hazardous 
  conditions could impact the morning commute.

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

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.

&&

$$

WAZ042-120700-
/O.CON.KOTX.WS.W.0003.000000T0000Z-210113T0000Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Twisp, Winthrop, 
Stehekin, Conconully, Loup Loup Pass, Stevens Pass, Plain, 
and Holden Village
300 PM PST Mon Jan 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 PM PST
TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 5 to 10
  inches in the valleys, and 8 to 16 inches in the mountains.
  Locally up to two feet above 5000 feet.

* WHERE...Mazama, Twisp, Winthrop, Stehekin, Conconully, Loup 
  Loup Pass, Stevens Pass, Plain, and Holden Village.

* WHEN...From 1 PM this afternoon to 4 PM PST Tuesday.

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

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

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.

&&

$$
160 
WWUS46 KOTX 120552
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
952 PM PST Mon Jan 11 2021

...HEAVY WET SNOW TONIGHT AND TUESDAY...

.A very moist storm is likely to bring moderate to heavy
precipitation overnight into Tuesday. Precipitaiton in the
Okanogan Highlands, Methow Valley, and along the Cascade Crest is
expected to fall as snow before transitioning to rain late
Tuesday. Snow rates could approach 1-2 inches per hour.

WAZ038-121400-
/O.CON.KOTX.WS.W.0003.210112T0600Z-210113T0000Z/
Okanogan Highlands-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
and Sherman Pass
952 PM PST Mon Jan 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 PM PST
TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations 3 to 7
  inches with locally up to a foot in the higher terrain.

* WHERE...Republic, Wauconda, Chesaw Road, Highway 20 Wauconda 
  Summit, Boulder Creek Road, and Sherman Pass.

* WHEN...Until 4 PM PST Tuesday.

* IMPACTS...Travel could be very difficult. The hazardous 
  conditions could impact the morning commute.

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

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.

&&

$$

WAZ042-121400-
/O.CON.KOTX.WS.W.0003.000000T0000Z-210113T0000Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Twisp, Winthrop, 
Stehekin, Conconully, Loup Loup Pass, Stevens Pass, Plain, 
and Holden Village
952 PM PST Mon Jan 11 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 PM PST
TUESDAY...

* WHAT...Heavy snow. Additional snow accumulations of 2 to 7
  inches in the valleys, and 7 to 15 inches in the mountains.

* WHERE...Mazama, Twisp, Winthrop, Stehekin, Conconully, Loup 
  Loup Pass, Stevens Pass, Plain, and Holden Village.

* WHEN...Until 4 PM PST Tuesday.

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

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

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.

&&

$$
013 
WWUS46 KOTX 121246
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
446 AM PST Tue Jan 12 2021

...HEAVY WET SNOW THROUGH TODAY...

.A very moist storm is likely to bring moderate to heavy
precipitation through Tuesday. Precipitaiton in the Okanogan 
Highlands, Methow Valley, and along the Cascade Crest is expected 
to fall as snow before transitioning to rain late Tuesday. Snow 
rates could approach 1-2 inches per hour.

WAZ038-042-130000-
/O.CON.KOTX.WS.W.0003.000000T0000Z-210113T0000Z/
Okanogan Highlands-East Slopes Northern Cascades-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
Sherman Pass, Mazama, Twisp, Winthrop, Stehekin, Conconully, 
Loup Loup Pass, Stevens Pass, Plain, and Holden Village
446 AM PST Tue Jan 12 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 4 PM PST THIS
AFTERNOON...

* WHAT...Heavy snow expected. Additional snow accumulations 3 to 
  7 inches with locally up to a foot in the higher terrain.

* WHERE...Mazama, Twisp, Winthrop, Stehekin, Loup Loup Pass,
  Stevens Pass, Plain, Republic, Wauconda, Chesaw Road, Highway 
  20 Wauconda Summit, Boulder Creek Road, and Sherman Pass.

* WHEN...Until 4 PM PST Tuesday.

* IMPACTS...Travel could be very difficult. The hazardous 
  conditions could impact the morning commute.

* ADDITIONAL DETAILS...Snow rates of one to two inches per hour 
  coupled with the weight of the snow could result in tree 
  damage and isolated power outages.

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.

&&

$$
058 
WWUS46 KOTX 122009
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
1209 PM PST Tue Jan 12 2021



WAZ038-042-122115-
/O.CAN.KOTX.WS.W.0003.000000T0000Z-210113T0000Z/
Okanogan Highlands-East Slopes Northern Cascades-
1209 PM PST Tue Jan 12 2021

...WINTER STORM WARNING IS CANCELLED...

Snowfall has changed over to rain and/or decreased substantially 
in intensity for most locations, therefore the winter storm 
warning has been cancelled.


$$

The office that day

Everything else NWS Spokane, WA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 11, 2:58 PM PSTHigh Wind WatchOTXAsotin, Garfield, Lincoln, Pend Oreille, Spokane, Stevens and 1 more14 hr

Nearby

Winter 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.