A strong westerly flow aloft ushered a prolonged period of heavy snow and strong winds into the north central mountains of Colorado. The combination of snow and wind resulted in a high avalanche danger.
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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 strong westerly flow aloft ushered a prolonged period of heavy snow and strong winds into the north central mountains of Colorado. The combination of snow and wind resulted in a high avalanche danger. An avalanche occurred along Interstate 70 between Frisco and Copper Mountain late in the afternoon on the 3rd. Several vehicles were trapped by the snow as it swept across the interstate. Another avalanche occurred near the same area earlier in the day. No injuries were reported and the vehicles were able to pull out of the snow field. Large stretch of I-70 now closed through the mountains. On the 5th, both directions of Interstate 70 between Herman Gulch and Silverthorne were closed for 9 hours for avalanche mitigation work. One of the avalanches brought down more snow than expected and covered the westbound lanes with 15 feet of snow and the eastbound lanes with 8 feet.
Storm totals for the 3-day event included: 35 inches at Mt Audubon; 32.5 near Mt Zirkel; 27.5 inches near Hoosier Pass, Longs Peak, Loveland Pass; 26 inches near Berthoud Falls, Climax, Glendevey and Silverthorne; 25.5 inches near Frisco; 22.5 inches near Guanella Pass; 20 inches near Cameron Pass; 19 inches at Brainard Lake; 16.5 inches near Ward; 15 inches near Alma, Eldora and Meeker Park.
In the Front Range Foothills, storm totals included: 17 inches near Estes Park; 11 inches near Georgetown and Nederland; 10 inches near Virginia Dale; 8.5 inches near Buckhorn Mountain and Glen Haven. Along the I-25 corridor and adjacent plains, storm totals included: 8.5 inches near Fort Collins; 8 inches near Elizabeth and Nunn; 7.5 inches near Loveland; 7 inches near Wellington; with 2 to 6 inches 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 28, 8:32 PM MST, 3 hours 28 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 832 PM MST Thu Feb 28 2019 .UPDATE... Issued at 831 PM MST Thu Feb 28 2019 Snow showers will continue to move across the mountains through tonight as a moist westerly flow aloft prevails. Looking at web cameras and radar, snowfall has been light so far. The snow showers will continue tonight with up to 4 inches of snow expected. Rabbit Ears Pass and north may see up to 7 inches of snow tonight. Latest forecast is on track with only minor changes to line up with current trends. UPDATE Issued at 511 PM MST Thu Feb 28 2019 Just issued Winter Storm Watches along the Front Range for the upcoming cold and snow. For the northern parts, including the Fort Collins area, will start it 5PM Friday. Models showing lift from the jet producing a band of snow along the Colorado/Wyoming border. For the rest of the Front Range will start the watch Saturday morning when snow is expected to move into the Denver area. Also put the mountain valleys in a Winter Weather Advisory. && .SHORT TERM...(This evening through Friday) Issued at 337 PM MST Thu Feb 28 2019 Drier and warmer has been the rule today due to southerly winds on the plains through the day. Mountain areas were dry earlier, but afternoon warming and mid-level moisture over the state are producing scattered snow showers. Mountain areas will continue seeing showers through the evening with a couple inches of accumulation over higher ridges. Moisture is expected to continue increasing Friday with more accumulations through the day. This will be the leading edge of the continuing flow of moisture through the weekend. An upper level jet will also be moving over the state, helping to enhance lift over the state. Mountain shower activity may begin impacting travel in the mountains by the afternoon hours. Scattered rain showers could also move out over the northeast Colorado plains late in the afternoon. Given the increasing chances of snow in the mountains, and the decrease in the amount of time that it will not be snowing over the next few days, have extended the Winter Storm Warning to also include zone 34. Model QPF fields show that eventually, just about all of the mountains in Colorado will be receiving significant snowfall. Questions remain about whether zones 30 and 32, North Park and Middle Park, will receive enough snow for any advisories. The overrunning pattern makes it possible that these mountain valley locations could see significant accumulating snows. .LONG TERM...(Friday night through Thursday) Issued at 337 PM MST Thu Feb 28 2019 Models have a jet maximum of westerly flow over the CWA Friday night into Saturday. Wind speeds are 100-140 knots at jet level. A weak upper trough will moves across and to the east Saturday evening. Strong flow aloft returns Sunday and Sunday night with a west-northwesterly direction. As far as the synoptic scale energy is concerned, the QG Omega fields show very weak upward vertical velocity Friday night through early Saturday afternoon. The upward motion is stronger Saturday afternoon and overnight. Downward motion is in place Sunday into the evening. The low level winds look to be east-southeasterly Friday night into mid day Saturday. A decent surge of colder air is progged to move in later Saturday afternoon with a more northeasterly low level flow behind it. Saturday night into Sunday night's winds will be east- northeasterly. They will be fairly weak Sunday afternoon and night. For moisture, it is plentiful Friday evening through Sunday morning. Moisture is not as deep Sunday and Sunday night, but there is still some around especially for the mountains. The QPF fields show decent amounts of measurable snow over the mountains. With the jet around, some synoptic scale energy, significant orographic enhancement and deep moisture, the ongoing highlight for heavy snow is right on track. The QPF fields over the plains are still a bit tricky; they differ considerably from model to model. There is some on all the models, with the highest amounts on the Cheyenne Ridge. The first shot of snow over the plains will only affect the northern third later Friday night into Saturday morning. All the plains are in the snow from later Saturday afternoon into Sunday morning through about 12Z. Highlights may be needed, advisories most likely if what we see now holds true. For temperatures, Saturday's highs will cool off 4-7 C from Friday's highs. Sunday's highs will be 2-5 C colder than Saturday's. For the later days, Monday through Thursday, models have strong zonal flow over the CWA Monday, then northwesterly flow aloft on Tuesday with an upper ridge to push across Colorado Tuesday night and Wednesday. On Thursday, southwesterly flow aloft becomes west- southwesterly. Moisture is pretty sparse Monday and Tuesday, with an increase Wednesday and Thursday. Temperatures will be way below seasonal normals on Monday, still below but warming on Tuesday, then near normals Wednesday and Thursday. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 831 PM MST Thu Feb 28 2019 VFR conditions are expected through Friday afternoon with mid and high clouds streaming across the area. Rain and snow showers will be possible late Friday afternoon and evening. Ceilings of 1000-3000 feet will be possible under the snow showers. There may be partial clearing Friday night before low clouds and snow set in for Saturday. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from Saturday morning through late Saturday night for COZ036-039>041-043. Winter Storm Watch from Friday afternoon through late Saturday night for COZ035-038-042. Winter Storm Warning until 5 AM MST Sunday for COZ031-033-034. Winter Weather Advisory until 5 AM MST Sunday for COZ030-032. && UPDATE...Meier SHORT TERM...Dankers LONG TERM....RJK AVIATION...Meier
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1051 AM MST Thu Feb 28 2019 COZ030>051-011800- 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- 1051 AM MST Thu Feb 28 2019 ...WINTER STORM WARNING FOR NORTHERN MOUNTAINS TONIGHT THROUGH SATURDAY... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Dry and mild conditions will prevail across the plains today with the coolest temperatures over the northeastern plains. In the mountains, gusty westerly winds will continue at speeds of 25 to 35 mph over the higher passes and wind prone east slopes. Snow will increase over the northern mountains later this afternoon and continue overnight. Snow may become heavy at times from Rabbit Ears Pass northward with accumulations of 5 to 10 inches possible. Elsewhere in the mountains, including Summit and eastern Grand Counties, snowfall will be lighter, generally in the 2 to 4 inch range tonight. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Snow, heavy at times, will continue in the northern mountains through Friday night. Along the I-70 mountain corridor snowfall will be much lighter. Over northeast Colorado snow will become likely Friday evening across northern portions of the front range urban corridor and adjacent plains. Accumulations of 1 to 4 inches will be possible. On Saturday snow will become widespread across all of the mountains by afternoon and continue through Saturday night. Over northeast Colorado a strong cold front will move across in the afternoon hours. Snow will become widespread across the plains and foothills by early Saturday evening and continue overnight. For Sunday snow will continue in the mountains with only a chance of light snow at lower elevations. Temperatures across northeast Colorado will be well below normal as readings only reach the teens for highs. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight.
The national radar mosaic for the moment the first event began.
9 winter weather, 4 winter storm, 1 avalanche. Local standard time, as filed.
An avalanche swept across I-70 and trapped vehicles in several inches of snow. No injuries or property damage was reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2019Every state in 2019This day in weather historyWarnings in Colorado, March 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: 799731, 799732, 799733, 799742, 799743, 799740, 799744, 799746, 799747, 799748, 799749, 799750, 799745, 799735.