A peak wind gust to 83 mph occurred near Berthoud Pass.
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The episode as NWS BOU wrote it up.
A peak wind gust to 83 mph occurred near Berthoud Pass.
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 Dec 7, 4:54 AM MST, 6 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Denver/Boulder CO 454 AM MST Thu Dec 7 2023 .KEY MESSAGES... - Mild and dry conditions continue today. - High winds up to 80 mph will occur over the Front Range Mountains and Foothills today. - The next system will bring snow and colder temperatures for the mountains and plains for Friday and Friday night. - Higher snow amounts confined to the southern foothills, Palmer Divide, and west slope mountain ranges. && .SHORT TERM...(Today and tonight) Issued at 333 AM MST Thu Dec 7 2023 As the thermal ridge exits, most of northeastern Colorado will experience another above normal day. Majority of the plains and parts of the foothills will climb into the mid 50s to mid 60s this afternoon. Additional mid-level moisture increases for the mountains which will likely bring increasing cloud cover for the higher terrain. Cross sections indicate strong stable layer aloft and tighten pressure gradients resulting in strong westerly flow across the mountains and foothills. Thus, the High Wind Warning will continue for these areas until 5 PM MDT this evening. It is likely these downslope winds will spread into parts of the urban corridor and plains producing wind gusts between 20-30 mph periodically this afternoon. These conditions may lead to spotty near critical fire weather conditions across the plains as humidities drop near the mid to upper teens. Considering these periods of gusty winds will be short-lived, no red flag highlights were issued but will continue to monitor if gusts become persistent than expected. Meanwhile late afternoon into this evening, winter returns to the western slopes as the next upper level trough approaches. Orographic flow will assist in developing light to moderate snow tonight into Friday morning for parts of the western slopes. Although winds decrease in speed overnight, patchy blowing snow conditions are possible along mountain passes. .LONG TERM...(Friday through Wednesday) Issued at 333 AM MST Thu Dec 7 2023 A broad and somewhat disorganized upper level trough will be over Colorado Friday and Friday night. Appears there are two short waves with in this trough. The first one moves across Friday morning, which will bring areas of snow to the plains for Friday. Snow will become light and also end in places late Friday morning and Friday afternoon. Temperatures will be near to slightly above freezing Friday across the lower elevation. We could end up with a little accumulation on the roads during the morning hours, but most roads across the lower elevations should be wet until late Friday afternoon due decreasing snow and above freezing temperatures. The second wave affects the area beginning late Friday afternoon through Friday night. This wave ends up digging southeast into New Mexico and produces a northerly flow across eastern Colorado. At the surface, a surge of northerly winds occur early in the evening. This will put the best chance for heavier snow Friday night over the southern foothills and Palmer Divide. Models are still bouncing around showing where the heaviest snow will occur, and thus confidence is on the low reside regarding snowfall amounts. On Saturday, north-northwest flow aloft will prevail behind the exiting system. Gusty northerly winds are expected across the eastern plains with gusts to 45 mph. The northerly flow will keep temperatures cool with highs mainly in the 30s over northeast Colorado. Light snow likely lingers in the mountains, at least during the morning hours. Any accumulations should be light and less than 2 inches. Northwest flow aloft prevails for Sunday and Monday. Models not showing a wave during this period, but run-to-tun consistency has been lacking, so will keep lower PoPs in the mountains. Temperatures will be near normal under this pattern with highs in the 40s over northeast Colorado. The forecast for Tuesday and Wednesday is still highly uncertain. Most models are showing a moisture starved closed low over the Great Basin and Desert Southwest. If this ends up being the case, we would expected near normal temperatures with little to no precipitation. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) Issued at 435 AM MST Thu Dec 7 2023 VFR conditions continue through the TAF period but low visibilities near MVFR conditions are possible due to incoming snow showers. This TAF issuance includes PROB30 near 15Z for potential snow showers arriving near KDEN. This morning, strong winds will develop across the mountains bringing downslope winds to the terminals near 18-19Z. Westerly winds will likely lead to a period of wind gusts up 25-30kts across all sites until 01-02Z. Drainage winds are unlikely as the next system approaches while decreasing cloud decks near 10-15k between SCT to BKN. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 11 PM this evening to 5 AM MST Saturday for COZ031. High Wind Warning until 5 PM MST this afternoon for COZ033>036. && SHORT TERM...AD LONG TERM...Meier AVIATION...AD
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 454 AM MST Thu Dec 7 2023 COZ030>051-081200- 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- 454 AM MST Thu Dec 7 2023 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Strong westerly winds are likely today across the mountains and foothills thus a High Wind Warning is in effect 5 AM to 5 PM today for wind gusts up to 65-80 mph. Spotty elevated to near critical fire weather conditions are possible this afternoon across the Palmer Divide and eastern plains due to the combination of low relative humidities near 15-20 percent and wind gusts between 20-30 mph. Tonight, light to moderate snow showers develop across the mountains. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Snow forms in the mountains late tonight and continues Friday. The mountain snow spreads onto the plains Friday and Friday night with periods of snowfall. Roads may become snow covered at times Friday, but there will be better chance for snow covered and slick roads Friday night when temperatures fall below freezing. For Saturday, snow becomes light and ends in the mountains. It will be windy across the eastern plains with gusts to 45 mph. .SPOTTER INFORMATION STATEMENT... Spotter reports of wind and snow are appreciated.
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2023Every state in 2023This day in weather historyWarnings in Colorado, December 2023
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: 1147340.