Alert archive / Idaho / Winter Storm Warnings in 2021

Winter Storm Warning 1, NWS Spokane, WA

January 2, 20214 counties in Idaho

NWS Spokane, WA issued this winter storm warning at Jan 2, 2021, 3:18 AM PST for 4 counties in Idaho. It took effect at Jan 2, 2021, 4:00 PM PST. It was in force for 20 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
Jan 2, 2021, 3:18 AM PST (11:18 UTC)
In effect from
Jan 2, 2021, 4:00 PM PST
Expired
Jan 3, 2021, 11:33 AM PST
In force
20 hr
Issued by
NWS Spokane, WA

Counties Benewah County, ID, Kootenai County, ID, Latah County, ID, Shoshone County, ID

The radar

The Spokane radar (KOTX), 97 km from the middle of the area, began a volume at 11:20 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

Spokane, WA (KOTX), launched 00:00Z, 11.3 hours before the alert went out and 49 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 2021-01-02Temperature 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 2021-01-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 155 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
1191 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
155 m²/s²
0-3 km storm-relative helicity
219 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

368 
WWUS46 KOTX 021118
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
318 AM PST Sat Jan 2 2021

...SNOW IN THE MOUNTAINS THIS WEEKEND...

An exiting low pressure system will result in light to moderate
snowfall over the Cascades and into the Idaho Panhandle this
morning. A stronger and wetter storm arrives fast on its heels
with snow increasing over the mountains this afternoon and this
evening. Heaviest snowfall is expected Saturday evening into
Saturday night where winter travel conditions is expected along 
Highway 2 west of Coles Corner to Stevens Pass and for travel over
Lookout Pass.

IDZ004-022300-
/O.UPG.KOTX.WS.A.0001.210103T0000Z-210103T1800Z/
/O.NEW.KOTX.WS.W.0001.210103T0000Z-210103T2000Z/
Central Panhandle Mountains-
Including the following locations Lookout Pass
318 AM PST Sat Jan 2 2021

...WINTER STORM WARNING IN EFFECT FROM 4 PM THIS AFTERNOON TO
NOON PST SUNDAY ABOVE 4000 FEET...

* WHAT...Heavy snow expected above 4000 feet. Total snow 
  accumulations of 8 to 15 inches. Winds gusting as high as 40 
  mph.

* WHERE...Lookout Pass.

* WHEN...From 4 PM this afternoon to noon PST Sunday.

* IMPACTS...Travel could be very difficult. Patchy blowing snow
  could significantly reduce visibility. Gusty winds could bring
  down tree branches.

* ADDITIONAL DETAILS...Light to moderate snow Saturday morning and
  afternoon will result in 3 to 5 inches of snow in the mountains.
  Snow becomes heavy Saturday night when winter travel conditions
  with hazardous travel is most likely.

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.

&&

$$

WAZ042-022300-
/O.NEW.KOTX.WW.Y.0001.210102T1800Z-210103T1800Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Stehekin, Stevens Pass,
Plain, and Holden Village
318 AM PST Sat Jan 2 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO
10 AM PST SUNDAY FOR THE CASCADE CREST INCLUDING HIGHWAY
2 BETWEEN COLES CORNER AND STEVENS PASS...

* WHAT...Snow expected for The Cascade Crest including Highway 2
  between Coles Corner and Stevens Pass. Total snow accumulations
  of 5 to 10 inches, except 10 to 20 inches expected above 4000 
  feet. Winds gusting as high as 45 mph.

* WHERE...Mazama, Stehekin, Stevens Pass, Plain, and Holden 
  Village.

* WHEN...From 10 AM this morning to 10 AM PST Sunday.

* IMPACTS...Travel could be very difficult. Wet heavy snow and 
  gusty winds could bring down tree branches.

* ADDITIONAL DETAILS...Snow levels are expected to rise Saturday
  afternoon to between 4000 and 4500 feet. There is uncertainty if
  snow will transition to rain at Stevens Pass. Heavier
  accumulations will occur if precipitation remains as snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$
4 follow-up statements
608 
WWUS46 KOTX 022151
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
151 PM PST Sat Jan 2 2021

...SNOW IN THE MOUNTAINS THIS WEEKEND...

Snow will increase in the mountains through Saturday night. 
Winter travel conditions is expected along Highway 2 west of 
Coles Corner to Stevens Pass and for travel over Lookout Pass. 
Another round of significant snow is expected on Monday.

IDZ004-030700-
/O.CON.KOTX.WS.W.0001.210103T0000Z-210103T2000Z/
Central Panhandle Mountains-
Including the following locations Lookout Pass
151 PM PST Sat Jan 2 2021

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

* WHAT...Heavy snow expected above 4000 feet. Total snow 
  accumulations of 8 to 15 inches. Winds gusting as high as 40 
  mph.

* WHERE...Lookout Pass.

* WHEN...From 4 PM this afternoon to noon PST Sunday.

* IMPACTS...Travel could be very difficult. Patchy blowing snow 
  could significantly reduce visibility. Gusty winds could bring 
  down tree branches.

* ADDITIONAL DETAILS...The heaviest snowfall is expected overnight
  into early Sunday morning with snow rates of one inch per hour
  likely.

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.

&&

$$

WAZ042-030700-
/O.CON.KOTX.WW.Y.0001.000000T0000Z-210103T1800Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Stehekin, Stevens Pass,
Plain, and Holden Village
151 PM PST Sat Jan 2 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
SUNDAY FOR THE CASCADE CREST INCLUDING HIGHWAY 2 BETWEEN COLES
CORNER AND STEVENS PASS...

* WHAT...Snow expected for The Cascade Crest including Highway 2 
  between Coles Corner and Stevens Pass. Total snow 
  accumulations of 5 to 10 inches, except 10 to 20 inches 
  expected above 4000 feet. Winds gusting as high as 45 mph.

* WHERE...Mazama, Stevens Pass, Holden Village.

* WHEN...From 10 AM this morning to 10 AM PST Sunday.

* IMPACTS...Travel could be very difficult. Wet heavy snow and 
  gusty winds could bring down tree branches.

* ADDITIONAL DETAILS...Snow level near 4000 to 4500 feet will
  result in wet snow or a rain and snow mix over Stevens Pass
  through the evening before changing to all snow around midnight
  as snow levels quickly drop to near 2000 feet.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

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

&&

$$
972 
WWUS46 KOTX 030540
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
940 PM PST Sat Jan 2 2021

...SNOW IN THE MOUNTAINS THIS WEEKEND...

Snow will be heavy at times across the mountains through Saturday
night. Winter travel conditions is expected along Highway 2 west 
of Coles Corner to Stevens Pass and for travel over Lookout Pass. 
Another round of significant snow is expected on Monday.

IDZ004-031400-
/O.CON.KOTX.WS.W.0001.000000T0000Z-210103T2000Z/
Central Panhandle Mountains-
Including the following locations Lookout Pass
940 PM PST Sat Jan 2 2021

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

* WHAT...Heavy snow expected above 4000 feet. Total snow 
  accumulations of 8 to 15 inches. Winds gusting as high as 40 
  mph.

* WHERE...Lookout Pass.

* WHEN...Through noon PST Sunday.

* IMPACTS...Travel could be very difficult. Patchy blowing snow 
  could significantly reduce visibility. Gusty winds could bring 
  down tree branches.

* ADDITIONAL DETAILS...The heaviest snowfall is expected 
  overnight into early Sunday morning with snow rates of one 
  inch per hour likely.

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.

&&

$$

WAZ042-031400-
/O.CON.KOTX.WW.Y.0001.000000T0000Z-210103T1800Z/
East Slopes Northern Cascades-
Including the following locations Mazama, Stehekin, Stevens Pass,
Plain, and Holden Village
940 PM PST Sat Jan 2 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
SUNDAY FOR THE CASCADE CREST INCLUDING HIGHWAY 2 BETWEEN COLES
CORNER AND STEVENS PASS...

* WHAT...Heavy snow expected for the Cascade Crest including
  Highway 2 between Coles Corner and Stevens Pass. Total snow
  accumulations of 6 to 12 inches, except 10 to 20 inches 
  expected above 4000 feet. Winds gusting as high as 45 mph.

* WHERE...Mazama, Stevens Pass, Holden Village.

* WHEN...Through 10 AM PST Sunday.

* IMPACTS...Travel could be very difficult. Wet heavy snow and 
  gusty winds could bring down tree branches.

* ADDITIONAL DETAILS...Snow rates of an inch an hour are expected
  across Stevens Pass through 3 AM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

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

&&

$$
594 
WWUS46 KOTX 031345
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
545 AM PST Sun Jan 3 2021

...MORE SNOW ON MONDAY AFTER PANHANDLE SNOW WINDS DOWN TODAY...

Lookout Pass will continue to see heavy snow through mid morning
with snow dissipating through the late morning hours. There will
be a break between weather systems this afternoon into this
evening. Another weather system moves in tonight with temperatures
expected to be colder at onset of precipitation. Valleys in 
north-central Washington are expected to see snow with heavy 
accumulations possible for the east slopes of the northern 
Cascades and Okanogan Highlands.

WAZ042-032145-
/O.CAN.KOTX.WW.Y.0001.000000T0000Z-210103T1800Z/
/O.NEW.KOTX.WS.A.0002.210104T0600Z-210105T0300Z/
East Slopes Northern Cascades-
Including the following locations Leavenworth, Mazama, Twisp, 
Winthrop, Stehekin, Conconully, Blewett Pass, Loup Loup Pass, 
Stevens Pass, Plain, and Holden Village
545 AM PST Sun Jan 3 2021

...WINTER STORM WATCH IN EFFECT FROM THIS EVENING THROUGH MONDAY
EVENING...
...WINTER WEATHER ADVISORY IS CANCELLED...

* WHAT...Heavy snow possible. Total snow accumulations of 6 to 10
  inches possible in the valleys and 10 to 20 inches possible for
  the mountains.

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

* WHEN...From this evening through Monday evening.

* IMPACTS...Travel could be very difficult.

* ADDITIONAL DETAILS...Snow is expected to switch over to rain in
  the Wenatchee River Valley up to Leavenworth by Monday 
  afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

IDZ004-032000-
/O.CON.KOTX.WS.W.0001.000000T0000Z-210103T2000Z/
Central Panhandle Mountains-
Including the following locations Lookout Pass
545 AM PST Sun Jan 3 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON PST TODAY
ABOVE 4000 FEET...

* WHAT...Heavy snow above 4000 feet. Additional snow 
  accumulations of 2 to 6 inches. Winds gusting as high as 40 
  mph.

* WHERE...Lookout Pass.

* WHEN...Until noon PST today.

* IMPACTS...Travel could be very difficult. Patchy blowing snow
  could significantly reduce visibility. 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.

&&

$$

WAZ038-032145-
/O.NEW.KOTX.WS.A.0002.210104T0800Z-210105T0300Z/
Okanogan Highlands-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
and Sherman Pass
545 AM PST Sun Jan 3 2021

...WINTER STORM WATCH IN EFFECT FROM LATE TONIGHT THROUGH MONDAY
EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 5 to 
  10 inches possible.

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

* WHEN...From late tonight through Monday evening.

* IMPACTS...Travel could be very difficult.

* ADDITIONAL DETAILS...Snow is expected to switch over to rain
  north along Highway 21 from Keller to Republic through the day 
  on Monday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
705 
WWUS46 KOTX 031933
WSWOTX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Spokane WA
1133 AM PST Sun Jan 3 2021

...MORE HEAVY SNOW FOR THE MOUNTAINS...THE METHOW VALLEY...AND THE
OKANOGAN HIGHLANDS MONDAY...

IDZ004-032045-
/O.CAN.KOTX.WS.W.0001.000000T0000Z-210103T2000Z/
Central Panhandle Mountains-
1133 AM PST Sun Jan 3 2021

...WINTER STORM WARNING IS CANCELLED...

Any additional snow accumulations for the mountains of the 
central Idaho Panhandle will be minimal this afternoon. More snow
will arrive on Monday and continue into Monday night.

$$

WAZ042-040000-
/O.CON.KOTX.WS.A.0002.210104T0600Z-210105T0300Z/
East Slopes Northern Cascades-
Including the following locations Leavenworth, Mazama, Twisp, 
Winthrop, Stehekin, Conconully, Blewett Pass, Loup Loup Pass, 
Stevens Pass, Plain, and Holden Village
1133 AM PST Sun Jan 3 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM 10 PM PST THIS
EVENING THROUGH MONDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 6 to 
  10 inches possible in the valleys and 10 to 20 inches possible 
  for the mountains.

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

* WHEN...From this evening through Monday evening.

* IMPACTS...Motorists should plan for winter driving conditions
  Monday into Monday evening.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

WAZ038-040000-
/O.CON.KOTX.WS.A.0002.210104T0800Z-210105T0300Z/
Okanogan Highlands-
Including the following locations Republic, Wauconda, 
Chesaw Road, Highway 20 Wauconda Summit, Boulder Creek Road, 
and Sherman Pass
1133 AM PST Sun Jan 3 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
MONDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 5 to 
  10 inches possible.

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

* WHEN...From late tonight through Monday evening.

* IMPACTS...Motorists should plan for winter driving conditions
  Monday into Monday evening.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

Nearby

Winter Storm Warnings in Idaho, 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.