A period of moderate to heavy snowfall occurred in the mountains and foothills mainly north of Interstate 70. 5 inches at Estes Park and 6 inches at Loveland Ski Area.
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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 BOU wrote it up.
A period of moderate to heavy snowfall occurred in the mountains and foothills mainly north of Interstate 70. Snowfall totals included: 10 inches at Eldora, 9.5 inches near Pingree Park, 7 inches at Arapaho Basin, 6.5 inches at Estes Park and 6 inches at Loveland Ski Area.
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 Denver/Boulder, CO wrote its last area forecast discussion before the first event at Jan 1, 9:16 PM MST, 6 hours 44 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 916 PM MST Sun Jan 1 2017 .UPDATE... Issued at 915 PM MST Sun Jan 1 2017 Increasing mid-level qg ascent and instability on the nose of a 100kt jet just ahead of a weak shortwave trough now passing over eastern Utah this evening continues to generate a growing area of light snowfall over western central Colorado. At this time precip looks more impressive on radar than it does on sfc observations and cams. Nonetheless...00z model data shows this area of lift and moisture tracking northeastward over the north central mtns and high valleys of Colorado in the next 3-6 hrs. Snowfall rates nothing terribly significant...possibly upwards of a inch per hour late tonight at higher elevations of the Park and Gore Ranges...and up along the Continental Divide around Summit County. Once the trough passes...the nwly flow aloft becomes zonal and speeds increase. It could become pretty windy on the ridges and high passes late tonight into Monday morning potentially causing blowing snow in open terrain. Otherwise at lower elevations east of the mtns...should see a gradual increase in high clouds overnight and even some mid-level cloud devlopment late with the approaching wave. Cross sections show a cross barrier wind component around 50kts near mtn top level towards morning. Could see some of this momentum moving downslope producing gusty winds in the lower foothills towards dawn. Otherwise looking for a dry and relatively mild night for the plains. Adjustments made to the 1st period forecast involve mainly timing issues. && .SHORT TERM...(This evening through Monday) Issued at 133 PM MST Sun Jan 1 2017 Normal afternoon upslope winds are in place across the plains and foothills right now. Speeds are fairly light. Lenticular cloudiness is developing over the plains and foothills too. There is no snow falling in the high country right now. There is weak flow aloft right now with a minor trough moving across. Models show the strong westerly jet level flow to return by 12Z Monday with speeds in the 100 to 120 knot range. The QG Omega fields show upward energy in the synoptic scale for the CWA tonight and Monday. The boundary layer flow will be weak drainage overnight, then southwesterlies Monday early with a cold front moving in during the afternoon Monday. For moisture, there is some in the mountains tonight and Monday, but it is pretty shallow. There is also a bit of upper level cloudiness expected noted on the cross sections and the satellite pictures upstream. All the models have a tad of measurable snowfall in the mountains from late evening tonight through Monday. Nothing significant and nothing for the plains. For pops, will keep the plains dry tonight and Monday. Will go with "chance"s in the mountains this evening, then "likely"s overnight and Monday. With the shallow moisture and not great orographic enhancement, highlight criteria snowfall amounts are not expected. For temperatures, Monday high's may be close to today's in most areas, but the cold air gets into the northeast corner by Monday afternoon. .LONG TERM...(Monday night through Sunday) Issued at 133 PM MST Sun Jan 1 2017 Overall trend has been for less moisture over CO through the week in spite of strong west/northwesterly flow aloft over the state so confidence in the models low to moderate at this time. Monday night, short wave moving around a broad upper trough over the Pacific Northwest will continue to stretch the trough in more of west-east orientation. A strong southwesterly flow aloft will be over northern CO with snow becoming widespread in the mountains west of the Continental Divide. Snowfall generally light to moderate however with just some weak mid level qg ascent over the mountains. A ridge develops over the west coast Tuesday afternoon into Wednesday with a strong northwesterly flow aloft CO. Mid level subsidence over the cwa at that time, so snowfall primarily the result of orographic production. Stronger winds will generally be above timberline. Spatial cross-sections indicate shallow moisture around but still fairly dry in the mid levels. As a result, just a slight chance of snow Monday night through Tuesday night, maybe a better chance of Wednesday but even that is suspect at this point. A strong northwesterly flow aloft will be over the region on Wednesday with an upper trough moving into the upper Midwest. Another surge of cold air on Wednesday but at this time, not much moisture aloft with strong mid level subsidence for the northeast plains. Most of the moisture remains trapped west of the ridge along the west coast so limited moisture may impact the mountains as well with mainly light snow in spite of a strong orographic component in the middle of the week. The trend of drier and warmer still okay by the weekend. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 915 PM MST Sun Jan 1 2017 VFR conditions next 12 hours as high clouds spread in from the west. drainage winds will dominate tonight at speeds generally under 12 kts. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && UPDATE...Baker SHORT TERM...RJK LONG TERM...Cooper AVIATION...Baker
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DENVER/BOULDER CO 1006 AM MST SUN JAN 1 2017 COZ030>051-021715- JACKSON COUNTY BELOW 9000 FEET- WEST JACKSON AND WEST GRAND COUNTIES ABOVE 9000 FEET- GRAND AND SUMMIT COUNTIES BELOW 9000 FEET- SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/ NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET- SOUTH AND SOUTHEAST GRAND/WEST CENTRAL AND SOUTHWEST BOULDER/ GILPIN/CLEAR CREEK/SUMMIT/NORTH AND WEST PARK COUNTIES ABOVE 9000 FEET-LARIMER AND BOULDER COUNTIES BETWEEN 6000 AND 9000 FEET- JEFFERSON AND WEST DOUGLAS COUNTIES ABOVE 6000 FEET/GILPIN/CLEAR CREEK/NORTHEAST PARK COUNTIES BELOW 9000 FEET- CENTRAL AND SOUTHEAST PARK COUNTY- LARIMER COUNTY BELOW 6000 FEET/NORTHWEST WELD COUNTY- BOULDER AND JEFFERSON COUNTIES BELOW 6000 FEET/WEST BROOMFIELD COUNTY- NORTH DOUGLAS COUNTY BELOW 6000 FEET/DENVER/WEST ADAMS AND ARAPAHOE COUNTIES/EAST BROOMFIELD COUNTY- ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET- NORTHEAST WELD COUNTY-CENTRAL AND SOUTH WELD COUNTY-MORGAN COUNTY- CENTRAL AND EAST ADAMS AND ARAPAHOE COUNTIES- NORTH AND NORTHEAST ELBERT COUNTY BELOW 6000 FEET/NORTH LINCOLN COUNTY- SOUTHEAST ELBERT COUNTY BELOW 6000 FEET/SOUTH LINCOLN COUNTY- LOGAN COUNTY-WASHINGTON COUNTY-SEDGWICK COUNTY-PHILLIPS COUNTY- 1006 AM MST SUN JAN 1 2017 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT THERE WILL BE A CHANCE OF SNOW SHOWERS OVER THE HIGH MOUNTAINS LATE THIS AFTERNOON AND TONIGHT. ACCUMULATIONS WILL BE INSIGNIFICANT. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY TEMPERATURES WILL TURN SIGNIFICANTLY COLDER LATER THIS WEEK WITH SOME SNOW EXPECTED AS WELL. THE MUCH COLDER AIR WILL BEGIN MOVING INTO THE REGION MONDAY AFTERNOON, WITH A STRONGER SURGE OF ARCTIC AIR ARRIVING TUESDAY AND WEDNESDAY. HIGHS MAY STRUGGLE TO REACH THE LOWER 20S BY WEDNESDAY AND THURSDAY. OVERNIGHT LOWS MAY DROP BELOW ZERO. IN ADDITION TO THE COLD, THERE WILL BE PERIODS OF SNOWFALL, ESPECIALLY IN THE MOUNTAINS. A SLIGHT CHANCE OF SNOW WILL SPREAD ONTO THE PLAINS MONDAY NIGHT OR TUESDAY MORNING. A BETTER CHANCE OF SNOW IS EXPECTED WEDNESDAY AND WEDNESDAY NIGHT. RELIEF FROM THE COLD TEMPERATURES IS NOT EXPECTED UNTIL AFTER FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.
The national radar mosaic for the moment the first event began.
4 winter weather. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2017Every state in 2017This day in weather historyWarnings in Colorado, January 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: 670133, 670134, 670135, 670136.