There was a brief period of moderate to heavy snowfall in the mountains with the passage of the storm system. Storm totals included: 10 inches at Deadman Hill and Long Draw Reservoir SNOTELS, 7 inches at Copper Mountain SNOTEL, with 6 inches at Hourglass Lake and Jones Pass SNOTELS.
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The episode as NWS BOU wrote it up.
There was a brief period of moderate to heavy snowfall in the mountains with the passage of the storm system. Storm totals included: 10 inches at Deadman Hill and Long Draw Reservoir SNOTELS, 7 inches at Copper Mountain SNOTEL, with 6 inches at Hourglass Lake and Jones Pass SNOTELS.
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 Feb 10, 4:13 AM MST, 1 hour 17 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 413 AM MST Sat Feb 10 2018 .SHORT TERM...(Today and tonight) Issued at 413 AM MST Sat Feb 10 2018 Cold air remains in place over the plains this morning. Low level flow is trying to turn southeast a bit, and slightly drier air has advected in from the east, so we have mainly flurries across the area at this hour, with light orographic snow on the summit of the Front Range. Today's snow band is taking shape along the Colorado/Wyoming border with a little enhancement/broadening as this shortwave develops a bit. This trend will continue as this area drops southeast across our area through the day today. Snow will increase over the mountains and areas north of Denver this morning, with the main period of snow for Denver midday into the afternoon, and lingering south of Denver into the evening. It still looks like 1-3 inches for most of the area, likely the lightest in the north and heavier in the south due to the development of the wave and just a little upslope enhancement. There will likely be some smaller scale banding making it more complicated, but those bands should be moving. For the mountains, some orographic enhancement, but the band will be the main issue. This will likely be over the I-70 corridor with about the same timing as Denver--late morning through the afternoon. Subsidence and drier air aloft moves in this evening, and skies should be clearing over the north by midnight and the whole area by morning. Temperatures would plummet, except for the low level southerlies on the plains that should already be developed, and probably a tendency toward a westerly component as well as the wave moves away. This should give most areas steady temperatures after midnight, possibly even rising a little in drainage areas. Some cold spots may need to be colder though, like the South Platte River bottom, Limon, and the valleys near the Wyoming border. .LONG TERM...(Sunday through Friday) Issued at 413 AM MST Sat Feb 10 2018 By Sunday morning the synoptic forcing will be south of our area, and we'll also be on the wrong side of the jet streak (left entrance). What about upslope and moisture? Very dry air will be advected with the northwest flow such that after 5 AM all PoPs for our area will be nil with seemingly everything working against precipitation production. The flow at 700 mb backs from north to west throughout the day, resulting in some modest warming across the east slopes and adjacent plains, but at best just the low 40s for the Denver metro area and east along the Palmer Divide where southwest downslope warming should help temperatures recover there in response to the surface high across the Southern Plains. Elsewhere across the Plains temperatures will stay in the 30s with the coolest readings from Greeley east along the Cheyenne Ridge terrain gradient where the inversion will hold tight. Early Monday the mid-level flow turns zonal as a trough moves onshore the Pacific Northwest and digs south towards the Great Basin. By midday enough moisture is advected ahead of the trough that upslope flow across the west slopes of the Central and Northern mountains looks like a good bet but accumulations look to be light. Across the Plains yet another shallow arctic front makes a run at Colorado and may become trapped against the Front Range and I-25 urban corridor by a Denver Cyclone likely to develop in the strong southeast flow further east across the Plains. Temps would thus remain chilly across the I-25 corridor but moderate further east across the Plains from south to north as low-level warm advection pushes the arctic air northward. Temps across the eastern Plains will not get out of the 30s. Will likely stay in the upper 20s across a good part of the I-25 urban corridor. Tuesday the Western U.S. trough cuts off and is pushed southwest into southern California by an omega block across the North Pacific. This should allow for continued light orographic snowfall across the west slopes of the central and lesser extent the northern mountains. Chance PoPs are appropriate but not much accumulation expected as the cut off low continues to move further southwest away from Colorado late Tuesday. Temperatures warm some across the Plains with the removal of a Denver Cyclone and partly cloudy skies. Looking like 40s for most areas of the Plains and continued dry with generally light winds. Wednesday through Friday the cut off low remains off the coast of southern California, and the Polar jet remains well north of us. A decent sub- tropical jet will be overhead or just south of Colorado during this time frame, downstream of the trough. Ensemble model output have surprisingly decent agreement on the jet position and general evolution of the offshore trough. Weak disturbances in the northwest flow may graze the northern mountains and bring a chance of light snow, but there is low confidence in those scenarios. We will retain low PoPs for the possibility of light west upslope snowfall throughout this period as it's pretty much impossible to nail the timing of these weak systems and attendant moisture content in these flow patterns 4+ days out. It's looking likely that the Plains will remain dry through Friday because Colorado could be in the unenviable position with the trough too far away to the southwest and the polar jet too far north. 700 mb flow is west throughout this period resulting in above normal temperatures from east of the Continental Divide across the Plains Wednesday and Thursday with highs in the 50s to near 60. On Friday a cold front may knock temps down 10-15 degrees but still in the mid to upper 40s other than the northeast Plains where the cold air is deeper. Only discernible impacts to watch mid week could be strong winds from the high mountains east to the adjacent Plains are a possibility Wednesday night into Thursday morning with hints of a good stable layer beneath a 100 kt jet with 50-60 kt flow at mountain tops. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 413 AM MST Sat Feb 10 2018 LIFR conditions will prevail through the day in the Denver area with light snow, possibly increasing for a few hours this afternoon. Conditions will improve as the snow ends between 03z and 07z, with clearing and VFR conditions expected between 07z and 10z. Snow accumulations of 2 to 3 inches are expected. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 5 PM MST this afternoon for COZ033- 034. && SHORT TERM...Gimmestad LONG TERM...Schlatter AVIATION...Gimmestad
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1106 AM MST Fri Feb 9 2018 COZ030>051-100615- 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- 1106 AM MST Fri Feb 9 2018 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight There will be areas of fog and flurries over the plains today with much colder temperatures. Today, intermittent light snow showers over the higher mountains, with west winds continuing to gust to 40 mph over the high mountains and the higher Front Range foothills. Snow will become more widespread over the mountains tonight, with freezing drizzle and snow developing on the plains. Accumulations will be light, but slippery roads may develop in many areas overnight. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Snowfall will continue on Saturday across much of the forecast area. The heavier snowfall is expected in higher mountain areas generally south of Interstate 70, and over portions of the Palmer Divide. Total snow accumulations by Saturday night will range from a trace to 3 inches on the plains, 2 to 5 inches in the Front Range foothills and Palmer Divide, and up to 10 inches in the high country. Snowfall should end in all areas by Sunday morning. There will be another chance for snow late Monday into Tuesday, mainly for the high country, with yet another opportunity for mountain snowfall Thursday and early Friday. .SPOTTER INFORMATION STATEMENT... Reports of snowfall or strong winds will be appreciated. Sullivan/Baker
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DENVER CO
136 AM MST SAT FEB 10 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0437 PM SNOW PEETZ 40.96N 103.11W
02/09/2018 M1.3 INCH LOGAN CO AMATEUR RADIO
0745 PM SNOW 2 E ALLENSPARK 40.20N 105.48W
02/09/2018 M1.0 INCH BOULDER CO TRAINED SPOTTER
0810 PM SNOW 2 N BOULDER 40.06N 105.25W
02/09/2018 M1.5 INCH BOULDER CO PUBLIC
0955 PM SNOW 3 SSW BOULDER 39.99N 105.27W
02/09/2018 M1.6 INCH BOULDER CO NWS EMPLOYEE
DAVID SKAGGS RESEARCH CENTER NOAA
1215 AM SNOW 3 W JAMESTOWN 40.11N 105.44W
02/10/2018 M3.3 INCH BOULDER CO TRAINED SPOTTER
&&
SCHLATTERThe national radar mosaic for the moment the first event began.
2 winter weather. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2018Every state in 2018This day in weather historyWarnings in Colorado, February 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: 739889, 739890.