A winter storm produced another round of moderate to heavy snow for portions of the north-central mountains. 5 inches, 9 miles south-southeast of Spicer; with 7 inches near Brainard Lake and Longs Peak.
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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 winter storm produced another round of moderate to heavy snow for portions of the north-central mountains. Storm totals included: 13 inches, 4 miles southeast of Mount Zirkel, 8.5 inches, 9 miles south-southeast of Spicer; with 7 inches near Brainard Lake and Longs Peak. Lesser amounts from 3 to 6 inches were observed elsewhere.
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 11, 2:56 PM MST, 1 hour 4 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 256 PM MST Thu Feb 11 2021 .SHORT TERM...(This evening through Friday) Issued at 224 PM MST Thu Feb 11 2021 For tonight, the models still show snow increasing in the mountains as the next storm system drops into the Great Basin. The models show generally weak to moderate qg ascent in the mid and upper levels but the best lifts will be south and west of Colorado. Ridgetop winds straight westerly at 45-50 kts around 650 mb. On Friday, this system will continue to drop southward into Arizona, as a speed max moving across the northern Rockies, moves into central Wyoming in the afternoon. This first feature will produce moderate to heavy snowfall across the northern mountains tonight, then it lessens on Friday as the dynamics aloft weaken. As far the urban corridor and northeast plains go, the stratus, fog and light snow that lifted this afternoon, will move back into the region this evening. This will follow another surge of northeast winds around 00z. Better mid and upper level moisture overrunning the arctic airmass may help generate slightly better snowfall late tonight into Friday morning. Colder on Friday, with max temperatures in Denver only warming to around 20F, with even colder readings north and east of the Denver. The combination of snow and wind will drop wind chill readings to around -20F late tonight and Friday so we issued a wind chill advisory for those areas that will be in effect from midnight tonight through 4 pm Friday afternoon. .LONG TERM...(Friday night through Thursday) Issued at 224 PM MST Thu Feb 11 2021 Everybody will get into the fun this weekend with winter in full swing with the coldest temperatures of the season and a good shot of widespread light snowfall Saturday night and early Sunday. For Friday night, one weak disturbance will brush the far northern zones with light snowfall before exiting late Friday night. The northeast corner could see a couple of inches of snow from that weak system while else where on the plains mainly flurries with little or no accumulation. The next stronger system will drop across Colorado Saturday night and Sunday, however the best synoptic scale lift will remain south of Colorado. Still, decent support aloft along with shallow upslope flow spells a decent light snowfall for much of the lower elevations. Snowfall amounts look to be in the 2-4 inch range in that period for the plains and another 4 to 8 inches for the mountains. Big story will be the very cold temperatures and possibly record breaking cold on Sunday and Sunday night with lows Sunday night from around -10 to -20F. Expect may need winter weather advisories for much of the county warning area, including low wind chill temperatures. There will be a slow moderation of temperatures through the middle of next week but there will still be an active pattern for the mountains with continued periods of light snow. Could see a few shots of light snow over the plains for late Tuesday and Wednesday. Temperatures will still be below normal, but mainly 30s. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 224 PM MST Thu Feb 11 2021 Northeast winds will increase by 00z this evening with stratus deck filling back into the terminals tonight, with more fog development possible by the morning. Light snow showers are also possible tonight, with just a dusting expected. It will be colder with visibilities and ceiling expected to improve again by Friday afternoon. && .BOU WATCHES/WARNINGS/ADVISORIES... Wind Chill Advisory from midnight tonight to 4 PM MST Friday for COZ042-044-046-048>051. Winter Weather Advisory until 5 AM MST Saturday for COZ031-033. && SHORT TERM...Cooper LONG TERM...Entrekin AVIATION...Cooper
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1008 AM MST Thu Feb 11 2021 COZ030>051-121715- 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- 1008 AM MST Thu Feb 11 2021 ...MORE SNOW FOR THE MOUNTAINS STARTING TONIGHT... ...NEAR RECORD COLD AND SNOW FOR LOWER ELEVATIONS THIS WEEKEND... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Light snow will gradually increase in coverage and intensity over the mountains today. A couple inches of snow is expected for the northern mountains by this afternoon, with several inches falling overnight. The highest totals through tonight will be across the Park Range. Over the plains, cool and calm conditions are expected once again. High temperatures over the far northeast will struggle to reach 10F. Temperatures over the urban corridor will likely reach the upper 20s to mid 30s today. Fog and a few snow showers will dissipate by early afternoon, but will redevelop again this evening and overnight. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Even colder air will move into Colorado Friday and this weekend. By the weekend temperatures will be approaching records, with lows below zero and highs in the single digits above zero expected across most of the plains. There will be areas of light snow or flurries on the plains Friday and Saturday. The most likely time for impactful snow looks like Friday afternoon through Sunday morning. Several inches of snow are expected, and with subzero temperatures and a little wind travel may become hazardous. For the mountains, snow will decrease on Friday, then increase again Saturday and continue through early Sunday. These periods will see moderate to briefly heavy snowfall over the higher elevations, but even the valleys and foothills will have several inches of snow that will likely make roads icy given the cold temperatures. The early part of next week will bring some moderation in temperatures. Light snow and windy conditions can be expected over the higher mountains. A chance of snow will return to the valleys and foothills by Tuesday, and there is a chance of light snow on the plains Wednesday. .SPOTTER INFORMATION STATEMENT... Spotter reports will not be needed today or tonight.
The national radar mosaic for the moment the first event began.
2 winter weather. Local standard time, as filed.
Storm totals ranged from 4 to 13 inches.
Storm totals ranged from 3 to 7 inches.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2021Every state in 2021This day in weather historyWarnings in Colorado, February 2021
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: 942783, 942784.