Alert archive / Idaho / Winter Storm Warnings in 2021

Winter Storm Warning 4, NWS Boise, ID

February 13, 20217 counties in Idaho

NWS Boise, ID issued this winter storm warning at Feb 13, 2021, 10:59 AM MST for 7 counties in Idaho. It was in force for 6 hr. 9 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
Feb 13, 2021, 10:59 AM MST (17:59 UTC)
Expired
Feb 13, 2021, 5:00 PM MST
In force
6 hr
Issued by
NWS Boise, ID

Counties Ada County, ID, Canyon County, ID, Elmore County, ID, Gem County, ID, Owyhee County, ID, Payette County, ID, Washington County, ID

The radar

The Boise radar (KCBX), 20 km from the middle of the area, began a volume at 17:59 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
Feb 13, 11:13 AM MSTSNOW 9.54 Ese Eagle, IDSTORM TOTAL.
Feb 13, 11:29 AM MSTSNOW 103 Sse Meridian, ID
Feb 13, 11:30 AM MSTSNOW 7.86 Sse Boise, IDSTORM TOTAL.
Feb 13, 12:05 PM MSTSNOW 96 Sw Boise, IDSTORM TOTAL.
Feb 13, 12:50 PM MSTSNOW 94 Se Boise, IDSTORM TOTAL.
Feb 13, 2:28 PM MSTSNOW 113 Sse Meridian, IDSTORM TOTAL.
Feb 13, 4:20 PM MSTSNOW 71 Wnw Trinity Lakes, IDSTORM TOTAL SNOWFALL AT TRINITY MTN SNOTEL. 7770FT.
Feb 13, 4:20 PM MSTSNOW 7Se Graham Guard Station, IDSTORM TOTAL SNOWFALL AT GRAHAM GUARD STATION SNOTEL. 5690FT.
Feb 13, 4:20 PM MSTSNOW 132 Nne South Mountain, IDSTORM TOTAL SNOWFALL AT SOUTH MOUNTAIN SNOTEL. 6500FT.

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

The nearest sounding before it

Boise Airport, ID (KBOI), launched 12:00Z, 6.0 hours before the alert went out and 16 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, Boise Airport, ID at 12:00Z on 2021-02-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLEL10008507005003002001001 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, Boise Airport, ID at 12:00Z on 2021-02-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 166 square meters per square second.19395878Sfc1 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
522 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
166 m²/s²
0-3 km storm-relative helicity
223 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

900 
WWUS45 KBOI 131759
WSWBOI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boise ID
1059 AM MST Sat Feb 13 2021

IDZ014-015-029-140000-
/O.CAN.KBOI.WS.W.0003.000000T0000Z-210214T0000Z/
/O.NEW.KBOI.WS.W.0004.210213T1800Z-210214T0000Z/
Upper Treasure Valley-Southwest Highlands-Owyhee Mountains-
1059 AM MST Sat Feb 13 2021

...WINTER STORM WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON...

* WHAT...Snow continuing. Additional accumulation up to two 
  inches. Winds gusting as high as 40 mph in the afternoon.

* WHERE...Upper Treasure Valley, Southwest Highlands and Owyhee 
  Mountains zones.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snow will decrease after passage of a cold
  front around midday.

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 can be obtained by calling 5 1 1.

&&

$$

IDZ012-140000-
/O.CAN.KBOI.WS.W.0003.000000T0000Z-210213T1800Z/
/O.NEW.KBOI.WS.W.0004.210213T1800Z-210214T0000Z/
Lower Treasure Valley ID-
1059 AM MST Sat Feb 13 2021

...WINTER STORM WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON...

* WHAT...Snow continuing. Additional accumulation up to one inch.
  Winds gusting as high as 35 mph in the afternoon.

* WHERE...Lower Treasure Valley ID zone.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snow will decrease after passage of a cold
  front around noon.

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 can be obtained by calling 5 1 1.

&&

$$

ORZ063-064-131900-
/O.CAN.KBOI.WS.W.0003.000000T0000Z-210213T1800Z/
Malheur County-Oregon Lower Treasure Valley-
1059 AM MST Sat Feb 13 2021 /959 AM PST Sat Feb 13 2021/

...WINTER STORM WARNING IS CANCELLED...

Snow has generally ended. However, west or northwest winds will 
gust to 35 mph in the afternoon.

$$

IDZ011-013-033-ORZ062-140000-
/O.CAN.KBOI.WW.Y.0008.000000T0000Z-210214T0000Z/
/O.NEW.KBOI.WW.Y.0009.210213T1800Z-210214T0000Z/
West Central Mountains-Boise Mountains-Upper Weiser River-
Baker County-
1059 AM MST Sat Feb 13 2021 /959 AM PST Sat Feb 13 2021/

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST /4 PM PST/
THIS AFTERNOON...

* WHAT...Snow continuing. Additional accumulations up to 3 inches
  except.

* WHERE...Mountains in Baker County, Oregon, and mountains north
  of the Snake Basin in Idaho.

* WHEN...Until 5 PM MST /4 PM PST/ this afternoon.

* IMPACTS...Plan on slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ016-030-140300-
/O.CAN.KBOI.WW.Y.0008.000000T0000Z-210214T1200Z/
/O.NEW.KBOI.WW.Y.0009.210213T1800Z-210214T0300Z/
Western Magic Valley-Southern Twin Falls County-
1059 AM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 8 PM MST THIS
EVENING...

* WHAT...Snow continuing. Additional accumulations up to two 
  inches.  Winds gusting as high as 40 mph in the afternoon.

* WHERE...Western Magic Valley and Southern Twin Falls County 
  zones.

* WHEN...Until 8 PM MST this evening.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$
3 follow-up statements
106 
WWUS45 KBOI 132026
WSWBOI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boise ID
126 PM MST Sat Feb 13 2021

IDZ012-132130-
/O.CAN.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
Lower Treasure Valley ID-
126 PM MST Sat Feb 13 2021

...WINTER STORM WARNING IS CANCELLED...

Snow has decreased to flurries or ended. No further accumulation
is expected.

$$

IDZ014-015-029-140000-
/O.CON.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
Upper Treasure Valley-Southwest Highlands-Owyhee Mountains-
126 PM MST Sat Feb 13 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow continuing. Additional accumulation up to two 
  inches. Winds gusting as high as 40 mph in the afternoon.

* WHERE...Upper Treasure Valley, Southwest Highlands and Owyhee 
  Mountains zones.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snow will decrease after passage of a 
  cold front around midday.

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 can be obtained by calling 5 1 1.

&&

$$

IDZ011-013-033-ORZ062-140000-
/O.CON.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
West Central Mountains-Boise Mountains-Upper Weiser River-
Baker County-
126 PM MST Sat Feb 13 2021 /1226 PM PST Sat Feb 13 2021/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST /4 PM
PST/ THIS AFTERNOON...

* WHAT...Snow continuing. Additional accumulations up to 2 inches. 

* WHERE...Mountains in Baker County, Oregon, and mountains north 
  of the Snake Basin in Idaho.

* WHEN...Until 5 PM MST /4 PM PST/ this afternoon.

* IMPACTS...Plan on slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ016-030-140300-
/O.CON.KBOI.WW.Y.0009.000000T0000Z-210214T0300Z/
Western Magic Valley-Southern Twin Falls County-
126 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS
EVENING...

* WHAT...Snow continuing. Additional accumulations up to two 
  inches. Winds gusting as high as 40 mph in the afternoon. 

* WHERE...Western Magic Valley and Southern Twin Falls County 
  zones.

* WHEN...Until 8 PM MST this evening.

* IMPACTS...Travel could be very difficult.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions can be obtained by calling 5 1 1.

&&

$$
895 
WWUS45 KBOI 132109
WSWBOI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boise ID
209 PM MST Sat Feb 13 2021

IDZ014-141400-
/O.CAN.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
/O.NEW.KBOI.WW.Y.0010.210215T0600Z-210215T1800Z/
Upper Treasure Valley-
209 PM MST Sat Feb 13 2021

...WINTER STORM WARNING IS CANCELLED...
...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM SUNDAY TO 11 AM
MST MONDAY...

* WHAT...Snow expected. Total snow accumulations of 1 to 3 
  inches, except up to 4 inches over the mountains.

* WHERE...Upper Treasure Valley zone.

* WHEN...From 11 PM Sunday to 11 AM MST Monday.

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

* ADDITIONAL DETAILS...Snow will change to rain Monday with
  temperatures rising to 40 degrees.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

ORZ062-141400-
/O.CAN.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
/O.NEW.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
Baker County-
109 PM PST Sat Feb 13 2021

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

* WHAT...Heavy snow. New snow accumulations of 3 to 5 inches
 possible, except up to 10 inches over the mountains.

* WHERE...Baker County zone.

* WHEN...From Sunday evening through Monday evening.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

IDZ029-141400-
/O.NEW.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
/O.CON.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
Owyhee Mountains-
209 PM MST Sat Feb 13 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...
...WINTER STORM WATCH IN EFFECT FROM SUNDAY EVENING THROUGH
MONDAY EVENING...

* WHAT...For the Winter Storm Warning, additional snow accumulations
  around one inch. Winds gusting as high as 45 mph.  For the Winter
  Storm Watch, heavy snow. New snow accumulations of 3 to 6 inches 
  possible, except up to 9 inches over the mountains. Winds could 
  gust as high as 35 mph with Monday's storm.

* WHERE...Owyhee Mountains zone.

* WHEN...For the Winter Storm Warning, until 5 PM MST this afternoon.
  For the Winter Storm Watch, from Sunday evening through Monday
  evening.

* 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. 

Monitor the latest forecasts for updates on this situation. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ015-140000-
/O.CON.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
Southwest Highlands-
209 PM MST Sat Feb 13 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow continuing. Additional accumulation up to two 
  inches. Winds gusting as high as 40 mph in the afternoon.

* WHERE...Upper Treasure Valley, Southwest Highlands and Owyhee 
  Mountains zones.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snow will decrease this afternoon after
  passage of a cold front.

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 can be obtained by calling 5 1 1.

&&

$$

IDZ013-141400-
/O.NEW.KBOI.WW.Y.0010.210215T0600Z-210216T0600Z/
/O.CON.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
Boise Mountains-
209 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...
...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM SUNDAY TO 11 PM
MST MONDAY...

* WHAT...For the current Winter Weather Advisory, snow, additional 
  snow accumulations up to one inch. For the second Winter 
  Weather Advisory, snow expected. Total snow accumulations of 4 
  to 7 inches, except up to 10 inches over the mountains. Winds 
  gusting as high as 35 mph with that storm.

* WHERE...Boise Mountains zone.

* WHEN...For the current Winter Weather Advisory, until 5 PM MST 
  this afternoon. For the second Winter Weather Advisory, from 
  11 PM Sunday to 11 PM MST Monday.

* IMPACTS...Travel could be very difficult.

* ADDITIONAL DETAILS...Snow will change to rain below 4000 feet
  Monday afternoon. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ012-ORZ064-141400-
/O.NEW.KBOI.WW.Y.0010.210215T0600Z-210215T1800Z/
Lower Treasure Valley ID-Oregon Lower Treasure Valley-
209 PM MST Sat Feb 13 2021 /109 PM PST Sat Feb 13 2021/

...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM MST /10 PM PST/
SUNDAY TO 11 AM MST /10 AM PST/ MONDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 3 
  inches.

* WHERE...In Oregon, Oregon Lower Treasure Valley zone. In 
  Idaho, Lower Treasure Valley ID zone.

* WHEN...From 11 PM MST /10 PM PST/ Sunday to 11 AM MST /10 AM 
  PST/ Monday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the morning commute.

* ADDITIONAL DETAILS...Snow will change to rain by noon Monday
  with temperatures rising to 40 degrees.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ028-141400-
/O.NEW.KBOI.WW.Y.0010.210215T0600Z-210216T0600Z/
Camas Prairie-
209 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM SUNDAY TO 11 PM
MST MONDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 4 
  inches. Winds gusting as high as 35 mph.

* WHERE...Camas Prairie zone.

* WHEN...From 11 PM Sunday to 11 PM MST Monday.

* IMPACTS...Plan on slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ011-033-141400-
/O.NEW.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
/O.CON.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
West Central Mountains-Upper Weiser River-
209 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...
...WINTER STORM WATCH IN EFFECT FROM SUNDAY EVENING THROUGH
MONDAY EVENING...

* WHAT...For the  Winter Weather Advisory, additional snow 
  accumulations of up to one inch. For the Winter Storm Watch, 
  heavy snow. Total snow accumulations of 4 to 7 inches possible,
  except up to 10 inches over the mountains possible.

* WHERE...West Central Mountains and Upper Weiser River zones.

* WHEN...For the Winter Weather Advisory, until 5 PM MST this 
  afternoon. For the Winter Storm Watch, from Sunday evening 
  through Monday evening.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

Monitor the latest forecasts for updates on this situation. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ016-030-140300-
/O.CON.KBOI.WW.Y.0009.000000T0000Z-210214T0300Z/
Western Magic Valley-Southern Twin Falls County-
209 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS
EVENING...

* WHAT...Snow continuing. Additional accumulations up to two 
  inches. Winds gusting as high as 40 mph in the afternoon.

* WHERE...Western Magic Valley and Southern Twin Falls County 
  zones.

* WHEN...Until 8 PM MST this evening.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

ORZ063-141400-
/O.NEW.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
Malheur County-
209 PM MST Sat Feb 13 2021 /109 PM PST Sat Feb 13 2021/

...WINTER STORM WATCH IN EFFECT FROM SUNDAY EVENING THROUGH
MONDAY EVENING...

* WHAT...Heavy snow. Total snow accumulations of up to 5 inches
  possible. Winds could gust as high as 35 mph.

* WHERE...Malheur County zone.

* WHEN...From Sunday evening through Monday evening.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snow will change to rain below 5000 feet
  Monday afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
200 
WWUS45 KBOI 132358
WSWBOI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boise ID
458 PM MST Sat Feb 13 2021

IDZ029-141300-
/O.EXP.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
/O.CON.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
Owyhee Mountains-
458 PM MST Sat Feb 13 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY EVENING
THROUGH MONDAY EVENING...
...WINTER STORM WARNING WILL EXPIRE AT 5 PM MST THIS AFTERNOON...

* WHAT...Heavy snow possible Sunday night and Monday. Total snow
  accumulations of 3 to 6 inches, with up to 9 inches over the 
  mountains possible. Winds could gust as high as 35 mph.

* WHERE...Owyhee Mountains zone.

* WHEN...From Sunday evening through Monday evening.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

IDZ015-140100-
/O.EXP.KBOI.WS.W.0004.000000T0000Z-210214T0000Z/
Southwest Highlands-
458 PM MST Sat Feb 13 2021

...WINTER STORM WARNING WILL EXPIRE AT 5 PM MST THIS AFTERNOON...

The heavy snow has ended. Any additional light snow will bring
little additional accumulation.

$$

IDZ013-141300-
/O.EXP.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
/O.CON.KBOI.WW.Y.0010.210215T0600Z-210216T0600Z/
Boise Mountains-
458 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM SUNDAY TO
11 PM MST MONDAY...
...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

* WHAT...Snow expected. Total snow accumulations of 4 to 7 inches,
  with up to 10 inches over the mountains. Winds gusting as high 
  as 35 mph.

* WHERE...Boise Mountains zone.

* WHEN...From 11 PM Sunday to 11 PM MST Monday.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ011-033-141300-
/O.EXP.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
/O.CON.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
West Central Mountains-Upper Weiser River-
458 PM MST Sat Feb 13 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY EVENING
THROUGH MONDAY EVENING...
...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 7
  inches with up to 10 inches over the mountains possible.

* WHERE...Upper Weiser River and West Central Mountains zones.

* WHEN...From Sunday evening through Monday evening.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

IDZ016-030-140100-
/O.EXT.KBOI.WW.Y.0009.000000T0000Z-210214T0000Z/
Western Magic Valley-Southern Twin Falls County-
458 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow is tapering off with little additional accumulation
  expected.

* WHERE...Southern Twin Falls County and Western Magic Valley 
  zones.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Travel will remain difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ012-014-ORZ064-141300-
/O.CON.KBOI.WW.Y.0010.210215T0600Z-210215T1800Z/
Lower Treasure Valley ID-Upper Treasure Valley-
Oregon Lower Treasure Valley-
458 PM MST Sat Feb 13 2021 /358 PM PST Sat Feb 13 2021/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM MST
/10 PM PST/ SUNDAY TO 11 AM MST /10 AM PST/ MONDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 3 inches.

* WHERE...In Oregon, Oregon Lower Treasure Valley zone. In 
  Idaho, Upper Treasure Valley and Lower Treasure Valley ID 
  zones.

* WHEN...From 11 PM MST /10 PM PST/ Sunday to 11 AM MST /10 AM 
  PST/ Monday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the morning commute.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

IDZ028-141300-
/O.CON.KBOI.WW.Y.0010.210215T0600Z-210216T0600Z/
Camas Prairie-
458 PM MST Sat Feb 13 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM SUNDAY TO
11 PM MST MONDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 4 
  inches. Winds gusting as high as 35 mph.

* WHERE...Camas Prairie zone.

* WHEN...From 11 PM Sunday to 11 PM MST Monday.

* IMPACTS...Plan on slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions can be obtained by calling 5 1 1.

&&

$$

ORZ062-063-141300-
/O.CON.KBOI.WS.A.0002.210215T0600Z-210216T0600Z/
Baker County-Malheur County-
458 PM MST Sat Feb 13 2021 /358 PM PST Sat Feb 13 2021/

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY EVENING
THROUGH MONDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 2 to 4 
  inches, except up to 6 inches over the mountains possible. Winds
  could gust as high as 35 mph.

* WHERE...Malheur County and Baker County zones.

* WHEN...From Sunday evening through Monday evening.

* IMPACTS...Travel could be very difficult.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Boise, ID wrote its last area forecast discussion before this winter storm warning went out at Feb 13, 9:23 AM MST, 1 hour 36 minutes earlier.

Area forecast discussion, Feb 13, 9:23 AM MST, 1 hour 36 minutes before
Area Forecast Discussion
National Weather Service Boise ID
923 AM MST Sat Feb 13 2021

.DISCUSSION...Ongoing winter storm will send a cold front across
western Idaho before noon and south-central Idaho mid afternoon.
The front will bring a period of enhanced snow followed by gusty
west/northwest winds (in the Snake Basin). At 9 AM MST KCBX radar
at Boise showed enhanced returns in western Idaho, likely
indicating the approaching cold front. The frontal band should
pass through the Boise metro between 10 AM and noon MST then
continue east, reaching the western Magic Valley around 2 PM.
Current winter storm warnings and advisories remain on track.
Total storm snowfall forecasts (beginning 5 PM MST Friday) have
been increased 1-2 inches in the Treasure Valley according to
amounts observed so far. Forecast amounts elsewhere seem on track
at this time.

&&

.AVIATION...MVFR to IFR conditions in snow and low clouds will
continue through early evening. Widespread mountain obscuration
as abundant moisture spreads across all TAF sites. Some improving
conditions west of KBNO and KBKE aft 13/18Z with improving
conditions across Southwest Idaho late this afternoon. Surface
winds: West to southwest 5 to 15 kts, except east to southeast
KTWF through KBOI through 13/18z. Wind shifting to northwest 15
to 25 kts and spreading eastward through the afternoon as the
front slides through the TAF sites. Winds aloft at 10kft MSL:
West 30 to 50 kts then 20 to 30 kts after 14/15z.

Sunday Outlook...A lull in activity is anticipated Sunday but
lingering snow showers are possible across the Idaho West Central
Mountains through the day. A return of wintry conditions
(MVFR/IFR conditions) in low clouds and precipitation Sunday night
thru Monday. Periods of mountain obscuration will continue. Snow
levels on the rise Monday.

&&

.PREV DISCUSSION...
SHORT TERM...Today through Monday night...Snowfall continues with
strongest reflectivity noted over the Treasure Valley and areas
south. Winter Weather related hazards remain in place with no
modifications. Snow will continue today and will be heavy at
times this morning. Improvement expected during the afternoon. A
cold front will arrive into eastern Oregon during the mid- morning
hours, and will mostly be through the area by the mid to late
afternoon hours. This front will bring areas of gusty to breezy
wind, which could create some areas of blowing snow for areas
where the moisture content of the snow was on the lower side.
Additionally, guidance continues to show a threat of freezing rain
for portions of the Treasure Valley this morning, mainly between
Ontario and Mountain Home for areas south of the interstate.
Conditions from this round of moisture should weaken this evening,
with drier conditions expected on Sunday. However, another surge
of moisture expected for Monday, with snowfall anticipated to
impact much of the forecast area. Snowfall amounts could again be
significant, with a potential for travel impacts. Numerical
guidance continues to fluctuate a bit on moisture content with
this upcoming system, with updates expected. Lingering snow will
keep temperatures on the cooler side for the next couple of days,
with values 10 to 15 degrees below normal.

LONG TERM...Tuesday through Saturday...Active weather pattern will
continue through the extended period as more system move through the
westerly flow aloft. Snow showers will be possible Tuesday as a weak
shortwave moves across the region. This isn't likely to bring as
much snow to the region as the previous systems. Upper level
ridge will amplify over the region on Wednesday into Thursday
ahead of another Pacific Storm system. A warm front will switch
the flow aloft to westerly allowing warm air aloft to move in
across the region. It's unclear with this will be strong enough
to remove the cold air in the valleys as models haven't been
handling the temperature profiles well. At the moment, have played
the forecast more pessimistic with the valley seeing mostly snow.
Ensembles show another system for the weekend though the details
vary quite a bit, thus confidence remains low. Again, the overall
extended guidance shows high temperatures in the lower 40s into
the weekend. However, this is likely optimistic since none of
these systems removes the entrenched cold air in the valleys.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 5 PM MST this afternoon
     IDZ014-015-029.
     Winter Weather Advisory until 5 PM MST this afternoon
     IDZ011-013-033.
     Winter Storm Warning until 11 AM MST this morning IDZ012.
     Winter Weather Advisory until 5 AM MST Sunday IDZ016-030.
OR...Winter Weather Advisory until 4 PM PST this afternoon ORZ062.
     Winter Storm Warning until 11 AM MST /10 AM PST/ this morning
     ORZ063-064.

&&

www.weather.gov/Boise
www.facebook.com/NWSBoise
www.twitter.com/NWSBoise

DISCUSSION...LC
AVIATION.....CR
PREV SHORT TERM...KB
PREV LONG TERM....JDS

In the hours before

Local storm report, Feb 13, 8:26 AM MST, 2 hours 33 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOISE ID
826 AM MST SAT FEB 13 2021

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

0700 AM     SNOW             4 SE MERIDIAN           43.56N 116.36W
02/13/2021  M5.9 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-27 MERIDIAN 3.9 SE.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0600 AM     SNOW             6 SE BOISE              43.55N 116.13W
02/13/2021  M5.1 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-21 BOISE CITY 6.1 SE.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0700 AM     SNOW             CENTERVILLE             43.90N 115.90W
02/13/2021  M5.0 INCH        BOISE              ID   COCORAHS

            COCORAHS STATION ID-BS-10 PLACERVILLE 3.6
            SE. THE PERIOD OF THE SNOW EVENT WAS 24
            HOURS.

0700 AM     SNOW             3 WSW GARDEN CITY       43.62N 116.30W
02/13/2021  M5.0 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-5 BOISE 4.4 WNW. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0700 AM     SNOW             4 SE BOISE              43.57N 116.14W
02/13/2021  M5.0 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-46 BOISE 4.7 ESE. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0700 AM     SNOW             5 SE MERIDIAN           43.57N 116.32W
02/13/2021  M5.0 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-11 BOISE 6.1 SW. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0800 AM     SNOW             4 NNE DONNELLY          44.78N 116.05W
02/13/2021  M4.7 INCH        VALLEY             ID   COCORAHS

            COCORAHS STATION ID-VL-1 MCCALL 9.3 SSE. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0730 AM     SNOW             5 SSE MERIDIAN          43.55N 116.35W
02/13/2021  M4.7 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-45 MERIDIAN 4.8 SSE.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0700 AM     SNOW             4 WNW HOMEDALE          43.65N 117.00W
02/13/2021  M4.2 INCH        OWYHEE             ID   COCORAHS

            COCORAHS STATION ID-OW-2 HOMEDALE 4.0 WNW.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0700 AM     SNOW             11 ENE BOISE            43.65N 115.99W
02/13/2021  M4.0 INCH        BOISE              ID   COCORAHS

            COCORAHS STATION ID-BS-8 BOISE CITY 12.3
            ENE. THE PERIOD OF THE SNOW EVENT WAS 24
            HOURS.

0655 AM     SNOW             3 SSE BOISE             43.57N 116.18W
02/13/2021  M4.0 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-30 BOISE 3.4 SE. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0530 AM     SNOW             2 SSE KUNA              43.47N 116.40W
02/13/2021  M3.9 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-7 KUNA 1.5 SSE. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0656 AM     SNOW             1 W HUSTON              43.61N 116.80W
02/13/2021  M3.0 INCH        CANYON             ID   COCORAHS

            COCORAHS STATION ID-CY-26 CALDWELL 7.3 WSW.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

1030 PM     SNOW             1 N IDAHO CITY          43.84N 115.83W
02/12/2021  M3.0 INCH        BOISE              ID   COCORAHS

            COCORAHS STATION ID-BS-7 IDAHO CITY 1.1 ESE.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0800 AM     SNOW             6 WSW HINES             43.53N 119.19W
02/13/2021  M2.0 INCH        HARNEY             OR   COCORAHS

            COCORAHS STATION OR-HY-5 HINES 6.2 WSW. THE
            PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0738 AM     SNOW             3 ESE FILER             42.54N 114.55W
02/13/2021  M2.0 INCH        TWIN FALLS         ID   COCORAHS

            COCORAHS STATION ID-TF-1 TWIN FALLS 4.9 WSW.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

0720 AM     SNOW             GOODING                 42.94N 114.71W
02/13/2021  M1.5 INCH        GOODING            ID   COCORAHS

            COCORAHS STATION ID-GD-3 GOODING 0.2 NNE.
            THE PERIOD OF THE SNOW EVENT WAS 24 HOURS.

&&
Local storm report, Feb 13, 9:47 AM MST, 1 hour 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOISE ID
947 AM MST SAT FEB 13 2021

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

0630 AM     SNOW             1 N BOISE               43.63N 116.20W
02/13/2021  M4.0 INCH        ADA                ID   COCORAHS

            COCORAHS STATION ID-AD-9 BOISE 2.1 NNE.

0700 AM     SNOW             1 NNE FILER             42.58N 114.61W
02/13/2021  M1.5 INCH        TWIN FALLS         ID   COCORAHS

            COCORAHS STATION ID-TF-7 FILER 0.6 NNE.

0700 AM     SNOW             1 NE MURPHY HOT SPRINGS 42.03N 115.35W
02/13/2021  M2.0 INCH        OWYHEE             ID   CO-OP OBSERVER

            CO-OP OBSERVER STATION MHSI1 MURPHY HOT
            SPRINGS.

0730 AM     SNOW             1 ENE MIDDLETON         43.71N 116.61W
02/13/2021  M3.0 INCH        CANYON             ID   COCORAHS

            COCORAHS STATION ID-CY-12 MIDDLETON 0.7 ENE.

0800 AM     SNOW             2 N GLENNS FERRY        42.98N 115.30W
02/13/2021  M1.0 INCH        ELMORE             ID   COCORAHS

            COCORAHS STATION ID-EL-1 GLENNS FERRY 1.6 N.

&&

The office that day

Everything else NWS Boise, ID issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 13, 10:59 AM MSTWinter Weather AdvisoryBOIAdams, Boise, Camas, Elmore, Gem, Gooding and 4 more6 hr
Feb 13, 2:09 PM MSTWinter Storm WatchBOIAdams, Gem, Owyhee, Valley, Washington12 hr
Feb 13, 2:09 PM MSTWinter Weather AdvisoryBOIAda, Adams, Boise, Camas, Canyon, Elmore and 8 more63 hr

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