A weak shortwave passed over Northern California on the night of the 26th into the early morning hours of the 27th.
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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 REV wrote it up.
A weak shortwave passed over Northern California on the night of the 26th into the early morning hours of the 27th.
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 Reno, NV wrote its last area forecast discussion before the first event at Jan 27, 2:13 AM PST, 6 hours 52 minutes earlier.
Area Forecast Discussion National Weather Service Reno NV 213 AM PST Sat Jan 27 2018 .SYNOPSIS... Light snow showers and gusty winds will affect communities near the Oregon border today. Otherwise, dry conditions with above normal temperatures are projected for all next week and possibly into mid-February as blocking high pressure builds along the West Coast. && .SHORT TERM... Today's brush-by system will bring some light snow accumulations to the Surprise Valley and extreme northern Washoe County. Generally, only an inch or two is expected through the late morning hours. So, overall impacts will be fairly minimal and mainly focused on slick driving conditions. Showers and breezes will quickly diminish early in the afternoon as the wave rapidly weakens as it lifts into the inter-mountain west. Otherwise, the upper level ridge is expected to sharply amplify by Sunday heralding an extended period of warm, dry conditions. High temperatures will be 8-15 degrees above average for Sunday and Monday. The only other mentionable weather parameter will be a slight increase in winds Monday night mainly along ridges as a dry front begins to approach the region. Boyd .LONG TERM...Tuesday through next weekend... Ridging will be the main story for much of next week. There will be a cold front that tries to move through Tuesday, but continuing with the recent trends, it is expected to remain north of the Oregon border. The one thing it will do is increase mixing with 30-35 kt 700 mb winds and some afternoon breezes. With the increased mixing and mild 700 mb temps, warm temperatures are expected in many of the valleys Tuesday with a few record highs possible. In the wake of the system later in the week, the ridge off the coast near 135W amplifies a little. This will bring a more NE surface flow with mild 700 mb temps of 2-4 C continuing. Mountain temps will remain mild in the 40s and 50s while the lower valleys will remain in the 50s. Air quality could become a concern along the Sierra Front late in the week. Beyond, it still looks dry, and the ridge looks to remain anchored off the coast. The question is will it be a flatter ridge like the GFS with milder conditions, or amplified like the EC which would allow stronger backdoor fronts, better mixing and cooler temps. Our current forecast is leaning toward the GFS scenario, but either are possible. It will remain dry with some degree of above average temperatures, but nothing excessive. X && .AVIATION... VFR conditions south of KSVE and Gerlach this morning, but some MVFR CIGS and IFR VIS in -SN at times through 18Z north of there. Breezy winds over the ridges there with gusts to 60 kts for mtn wave turbulence in that area as well. After this moves through, expect lighter winds Sunday and monday along with VFR conditions for all terminals. X && .REV Watches/Warnings/Advisories... NV...None. CA...None. && For more information from the National Weather Service visit... http://weather.gov/reno
The national radar mosaic for the moment the first event began.
1 avalanche. Local standard time, as filed.
A dry slab avalanche was triggered by a snowboarder on North Castle Peak near the Donner Summit Area at 0905PST 27 January. The crown height was 1 foot. The avalanche length and width were 150 feet and 60 feet, respectively. No injuries were reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2018Every state in 2018This day in weather historyWarnings in California, January 2018
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: 737985.