Many slide offs were reported south of Pocatello between Pocatello and Downey in interstate 15. 3 inches fell in Downey and 5 inches in Inkom causing the very slick roads.
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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 PIH wrote it up.
Many slide offs were reported south of Pocatello between Pocatello and Downey in interstate 15. 3 inches fell in Downey and 5 inches in Inkom causing the very slick roads.
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 Pocatello, ID wrote its last area forecast discussion before the first event at Dec 29, 3:05 AM MST, 55 minutes earlier.
Area Forecast Discussion National Weather Service Pocatello ID 305 AM MST Sun Dec 29 2019 .SHORT TERM...Today through Tuesday. Radar imagery has filled in quite dramatically early this morning, with very light snow increasing in coverage across East Idaho. Shortwave trough dropping through northerly flow does not have a lot of moisture with it, so overall snow totals are generally light and expected to create nuisance impacts for travel through the day. Totals are generally less than an inch for most travel corridors, and 1-3 for higher elevations particularly the central mountains and southern highlands. On one hand, these amounts remain below any advisory thresholds, but are within the range of conditions that may be deceiving for drivers. Will likely update the current special weather statement to highlight slippery conditions for travel today. Upper ridge folds over the region tonight for break in the pattern into early Tuesday. Lower elevations may be susceptible to fog/stratus and have trended in this direction for sky and temperatures, but left fog out of the forecast for now. Flow begins to flatten ahead of stronger westerly flow and more moisture incoming into the region for the remainder of the forecast. Could see a few light snow showers across northern zones late in the day Tuesday. DMH .LONG TERM...Tuesday night through Sunday. Much more vigorous westerly flow sets up through the rest of the week. Two main systems are expected to impact the region, mainly Wednesday and Friday. The Wednesday storm does bring more moisture to the region, but best snowfall remains over higher elevations. Current forecast maintains generally 3-8 higher elevations and 1-3 for lower elevations including the Snake Plain. Complications include a slight warm up in temperatures - not enough to mix to liquid, but enough to reduce snow ratios. Winds also a complication under influence of the strong westerlies aloft. Weak dirty ridge tries to develop Wednesday night through Thursday, but orographic influence likely too strong and thus maintain precipitation chances across the region. Second more vigorous feature drives through on Friday with similar snow conditions but potentially stronger winds. This is still the feature to watch for more widespread blowing snow impacts, though guidance has backed off slightly on wind speeds for the day. Trough axis finally drives through Saturday per ensemble means, which could mean the stronger winds hold off for this time period, depending on how much mixing can be realized especially through lower elevations. Unsettled conditions could linger into Sunday, with cooler temperatures finally settling into the region. DMH && .AVIATION...Mid-level warm advection is underway early this morning, and this forcing has allowed for light snow to blossom across SE Idaho. Snow has already arrived at BYI and PIH as of 10Z, with snow on the doorstep of IDA. Given the spotty nature of the activity, it will be difficult to pin down duration, intensity and ultimate CIG/VIS. In light of that, we'll offer a general expectation, and that is for BYI and PIH too see the most snow, with MVFR conditions predominately expected, although heavier snow could result in a drop to IFR. For SUN, most of the snow should remain away from the terminal, but light snow could briefly drift in and result in MVFR ceilings. In terms of IDA, IFR ceilings are in place as of this writing, but as snow develops, conditions could actually improve to MVFR, except in heavier snow -- and this improvement should take place by 12Z. For DIJ, the bulk of the snow will remain west of the terminal, and we expect low predictability fog/stratus to slosh around the Teton Valley through the period, resulting in anywhere from VFR to IFR conditions. The snow is expected to come to an end at IDA first between 00-03Z this evening, then PIH between 03-06Z, and finally BYI between 06-09Z, leaning towards a later time. General MVFR to VFR low to mid level clouds are expected to linger after the conclusion of the snowfall. Winds are expected to remain at less than 12kt through the period at all TAF sites. AD && .PIH WATCHES/WARNINGS/ADVISORIES... None. &&
The national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Many slide offs were reported south of Pocatello between Pocatello and Downey in interstate 15. 3 inches fell in Downey and 5 inches in Inkom causing the very slick roads.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2019Every state in 2019This day in weather historyWarnings in Idaho, December 2019
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: 868274.