A slow moving upper low tracking across the southern border of Idaho spread heavy snow across parts of South Central Idaho.
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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.
The episode as NWS BOI wrote it up.
A slow moving upper low tracking across the southern border of Idaho spread heavy snow across parts of South Central Idaho.
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 Boise, ID wrote its last area forecast discussion before the first event at Feb 23, 3:11 AM MST, 5 hours 49 minutes earlier.
Area Forecast Discussion National Weather Service Boise ID 311 AM MST Thu Feb 23 2017 .SHORT TERM...Today through Friday...A slow moving upper low positioned over s-central Idaho this morning will keep snow over central Idaho into Friday. Focus of the heaviest snow will be across the eastern Boise mountains, Camas Prairie, Snake Plain (east of Mountain Home) to the ID/NV border where an additional 1 to 4 inches is expected. To the west of this band, expect light snow showers today as an upper level weakness tracks through southeast Oregon. Accumulations from this activity will be less than an inch and only on grassy surfaces across lower elevations. Drier air moves in from the west tonight, cutting off snow showers for all but central ID zones where moisture continues to wrap around the low over s-central ID. This feature does eventually lift into southwest MT during the day Friday bringing an end to the snow for all but the central ID mountains. Surface low over eastern ID will sustain gusty northwest winds across much of the region today into tonight. Strongest winds will channel from the Baker Valley through the Snake Plain where gusts of 30-40 MPH are likely. Winds will weaken late tonight into Friday as the surface low fills and lifts to the northeast. With a broad upper trough over the area temperatures will remain about 10 degrees below normal through Friday. For the current suite of products. Flow on the Malheur at Vale is continuing to drop and will likely be enough below flood stage to cancel the warning this morning. Feel winter highlights are adequate for the expected additional accumulations and accompanying impacts. Areas from Glenns Ferry and Bruneau south and east will see the most accumulating snow through this evening, though accumulations on paved surfaces will likely be diminished after 18Z. Did extend timing on Southwest Highlands zone by 3 hours to cover snowfall into early afternoon. .LONG TERM...Friday night through Wednesday...Cold active weather pattern will continue through Tuesday with the passage of two upper level troughs. Models remain consistent in keeping the first trough on Friday night into Saturday well off the west coast with the forecast area remaining largely unaffected. Showers could develop over the higher terrain Saturday afternoon but snow accumulations will be little if any. This trough weakens as it shifts southeast across California Saturday night. A second stronger and more moisture trough moves along the coast Sunday before shifting inland late Monday into Tuesday. Models still don't have a great handle on this system and differ with how far south the trough drops Monday before moving inland. This mainly has implications with the extent of shower coverage Sunday afternoon through Monday. Northwesterly flow will continue the changes for snow showers on Tuesday. Snow amounts will be light with a few inches in the mountains to little if any accumulations in the valley as the ground and surface temperatures remain at or above freezing Sunday through Monday. Upper level ridge begins to build along the west coast Wednesday and remaining through the weekend. It's not particularly strong but it will keep the area dry with temperatures climbing back to seasonal normals by Thursday. && .AVIATION...Generally low VFR, except for MVFR-IFR in snow east of a line from KREO-KMUO-KSUN. Snow will generally taper off this morning, except in central ID mountains and Magic Valley where snow will continue through Friday morning. Winds aloft at 10kft MSL: NW- NE 20-35kt. Surface winds generally W-NW 5-15kt becoming W-NW 15- 25kt Thu afternoon, gusts to 35kt in Baker, Treasure and Magic Valleys during the afternoon. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Winter Storm Warning until 11 PM MST this evening IDZ016-030. Winter Weather Advisory until 2 PM MST this afternoon IDZ015. OR...None. && www.weather.gov/Boise www.facebook.com/NWSBoise www.twitter.com/NWSBoise SHORT TERM...DG LONG TERM....JS AVIATION.....JS
The national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
Six to 12 inches of heavy snow fell across the Western Magic Valley with drifts of 2 to 3 feet reported by social media. The National Weather Service was informed by the FAA that the Twin Falls airport was closed due to drifts several feet deep.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2017Every state in 2017This day in weather historyWarnings in Idaho, February 2017
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: 690721.