Intense but very localized winds developed near the foothills of northern Jefferson and southern Boulder counties. Peak wind gusts included: 81 mph at the NCAR Mesa Lab, 2 miles southwest of Boulder; 80 mph at White Ranch Open Space, and 79 mph at the mouth of Coal Creek Canyon at the junction of CO72/CO93.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
Intense but very localized winds developed near the foothills of northern Jefferson and southern Boulder counties. Peak wind gusts included: 81 mph at the NCAR Mesa Lab, 2 miles southwest of Boulder; 80 mph at White Ranch Open Space, and 79 mph at the mouth of Coal Creek Canyon at the junction of CO72/CO93.
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 Nov 14, 4:48 PM MST, 1 hour 5 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 448 PM MST Sun Nov 14 2021 .SHORT TERM...(This evening through Monday) Issued at 212 PM MST Sun Nov 14 2021 Northwest flow aloft around a ridge over the Great Basin brought windy conditions to the higher foothills and Front Range mountains. This ridge will flatten and shift east over Colorado for Monday. With weakening flow aloft, don't expect it to be as windy tonight in the higher foothills and mountains, but gusts to 50 mph will be possible. The airmass will continue to warm tonight. It should be a mild night above the inversion and where winds mix the airmass. For Monday, 700mb temperatures warm to about 7-9C which should push highs into the mid 70s. Cross sections show enough moisture for high clouds at times, but not enough low level moisture over the mountains for any clouds or flurries. .LONG TERM...(Monday night through Sunday) Issued at 240 PM MST Sun Nov 14 2021 Models have flat upper ridging moving east of the CWA Monday night into Tuesday morning. The flow aloft increase Tuesday afternoon and night with a weak upper trough to push across the forecast area. The biggest affect on our weather will be a decent cold front that moves across Tuesday evening. The QG Omega fields show upward vertical velocity for the CWA late Monday night and Tuesday. Subsidence is progged after that through Wednesday night. Moisture over the CWA is lacking Monday night into Tuesday. Even with the upper trough moving across and the associated cold front with upslope behind it Tuesday afternoon into Wednesday; moisture is still meager. Will go with "likely"s Tuesday night in the mountains for light snow. On the plains, will go with 10-30%s from midnight Tuesday night through noon Wednesday. The QPF fields on the ECMWF shows a bit of measurable snowfall in a few areas of the plains with that. The amounts are light and the other models have nothing. Temperatures are still warm on Tuesday. Wednesday's highs cool off significantly from Tuesday's. For the later days, flat upper ridging is progged for the CWA on Thursday and Friday. The weekend looks to have weak upper troughing in place. As a result there will be "chance"s of alpine snow showers but nothing significant. The plains look dry with near normal temperatures. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 423 PM MST Sun Nov 14 2021 VFR conditions will continue through the TAF period. Gusty west to northwest winds will begin to decrease by 01Z shifting southwesterly tonight into early Monday morning; therefore typical drainage winds are unlikely. Wind gusts will increase to 20-25kts starting as early as 14Z at KDEN and KAPA and KBJC following after at 17Z. By Monday evening, wind gusts will decrease by 00Z with SCT high cloud bases at 20k ft. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && SHORT TERM...Meier LONG TERM....RJK AVIATION...AD
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1107 AM MST Sun Nov 14 2021 COZ030>051-151815- 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- 1107 AM MST Sun Nov 14 2021 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight It will continue windy from the higher terrain across the plains. A few wind gusts from 60 mph to 70 mph will occur, over the higher terrain, both today and tonight. Across the plains gusts from 30 to 40 mph will occur this afternoon. .DAYS TWO THROUGH SEVEN...Monday through Saturday Warm and dry weather is expected into early next week. Monday will be the warmest day with highs in the mid 70s for Denver and the rest of the plains. Gusty winds are also likely across the high country each day. A weak storm system will bring slightly cooler temperatures along with breezy to windy conditions across the forecast area on Tuesday. The warm, breezy and dry conditions will lead to elevated fire danger across the Southern Foothills, Palmer Divide and nearby plains Tuesday afternoon. Tuesday night, the high country will see a chance of light snow with a few light rain and snow showers possible across the plains. Cool weather should continue into next weekend with highs near normal. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight.
The national radar mosaic for the moment the first event began.
3 high wind. Local standard time, as filed.
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, November 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: 991045, 991046, 991047.