A strong cold front moved north to south through the region during the late evening hours on December 5th. A strong non-thunderstorm wind gust was reported at Trinidad Airport.
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The episode as NWS PUB wrote it up.
A strong cold front moved north to south through the region during the late evening hours on December 5th. A strong non-thunderstorm wind gust was reported at Trinidad Airport.
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 Pueblo, CO wrote its last area forecast discussion before the first event at Dec 5, 3:52 AM MST, 2 hours 52 minutes earlier.
Area Forecast Discussion National Weather Service Pueblo CO 352 AM MST Sun Dec 5 2021 .SHORT TERM...(Today and tonight) Issued at 352 AM MST Sun Dec 5 2021 ...Red Flag Warnings expanded today for the southeast mountains, I-25 corridor and adjacent plains... Key Messages 1) Red Flag Warnings expanded for SE Mountains/adjacent plains 2) Up to 50 mph northerly wind gusts for southeast plains late afternoon and evening behind cold front with blowing dust possible Cold front has slowed down in latest model runs suggesting a warmer and windier day across southern CO. Upper trough will continue to carve out across the northern U.S. Rockies as its associated upper jet translates south southeastward into northern CO by this afternoon/evening. Winds across the high country and along the lower eastern slopes have been steadily increasing overnight, keeping temperatures mild with readings in the 40s and 50s for the lower eastern slopes and portions of the I-25 corridor. Highest wind gust seen so far in mesonet sensors has been 51 mph on the top of Pikes Peak. Could see some further increases this morning up in Chaffee county and Pikes Peak area though high res models keep wind gusts below high wind criteria (75 mph for higher elevation). Humidity values are already pretty low with values around 20 percent in the windier areas. With a slower southward progression of the cold front, Red Flag warnings have expanded northward and eastward a tier of counties/zones and now encompasses all of the Pikes Peak region as well as Crowley, Otero and Las Animas counties. Have also expanded it into zone 225 (Wets and Sangre De Cristo mountains) though mainly for the lower eastern slopes below 8500 feet. There will be some lulls in wind gusts initially to the lee of Pikes Peak but still getting sufficient areal coverage and duration to warrant inclusion of all of El Paso county in the warnings. Dew points are already near 0 at AFF and other locations across the higher elevations, which is over-achieving in comparison to high res models and model blends. Leaned dew points towards the drier side of the spread and probably didn't go low enough. Even riding the conservative side, we should easily make critical relative humidity values late this morning through the afternoon across most of the southeast plains. Should see the wind shift with the cold front moving into northern El Paso around 20z but even then...higher dew points lag behind the front some which should keep Red Flag conditions going through 23z for northern areas. Cold front makes a strong push through the southeast plains between 00z and 03z with the potential for gusts around 50 mph. This could pick up areas of blowing dust, especially in the 00z-03z timeframe along and behind the cold front across the eastern plains. There is the potential for vis to drop below 1 mile briefly behind the front with the initial surge...though think the eastern most counties stand the best chance for seeing this. We could see some brief Red Flag conditions for the eastern zones behind the front as well, but with humidity values increasing some we may not get the full 3 hours required for a Red Flag expansion any further east. Will continue to monitor this potential. Otherwise...winds should gradually decrease towards 06z with front banking up along the eastern slopes of the southeast mountains. Could see some stratus develop along/west of I-25, especially for El Paso county where winds shift around from the southeast towards 12z with with the potential for enhanced wind speeds 10-15 kts. If low levels were more moist, this could be a set up for FZDZ...but soundings are rather dry at the surface as core of single digit dew points drops down behind the front across the eastern plains. Think this will be a shallow stratus event for the eastern slopes which will develop towards 09z and continue into Monday morning. Otherwise, forecast area remains dry today. Not to leave out mention of the mountains today, but with heights aloft decreasing the should see a slight cool down from yesterday. Expect gusty northwest winds 20 to 40 mph in and near the mountains with higher gusts across the higher elevations. Temperatures tonight should drop into the teens for all areas with single digit readings in some of our colder valleys. -KT .LONG TERM...(Monday through Saturday) Issued at 352 AM MST Sun Dec 5 2021 Key Messages 1) Cool temperatures on the plains Monday with a quick shot of mountain snowfall Monday night and Tuesday. 2) Potential for more widespread precipitation late week. Latest model data continues to indicate a broad upper trough translating across the region Monday and Tuesday, with the main energy splitting north and south of the area as it translate across the Rockies, leading to only a brief period of expected snowfall Monday night into early Tuesday, mainly across the higher terrain along the Continental Divide. High temperatures on Monday will be tricky, especially across the plains, as Sunday's passing cold front will usher in a shallow cold airmass which will be banked up across the lower eastern slopes where patchy stratus will also be in place early in the day. Increasing westerly flow through the day will lead to lee troughing and downslope winds, trying to scour out the cold air, which it could do across portions of the southern I-25 Corridor leading to temperatures warming into the 40s. Further north and east, breezy south to southeast upslope winds could keep the shallow airmass in place with temperatures struggling to get out of the 30s, especially in the Pikes Peak region south of the Palmer Dvd, where stratus could be in place through most of the day. Further west, temperatures on Monday warm into the 40s and 50s, save for 20s and 30s at the peaks. By late Monday afternoon, westerly flow ahead of the broad upper trough moving across the Great Basin will develop orographic snowfall across the Continental Divide, which looks to increase into Monday night and early Tuesday, before the system continues to translate across the Rockies and into the High Plains. With the latest models converging on energy splitting across the region, snow accumulations of 1 to 3 inches will be likely across the higher peaks of the central and southwestern mountains, along with local accumulations of up to an inch across the rest of the higher terrain with scattered showers associated with the passing trough on Tuesday. The passing system also helps to scour out the shallow cold airmass across the plains, with highs on Tuesday nearing seasonal norms in the 40s to lower 50s. Northwest flow moderates across the region on Wednesday and becomes more westerly ahead of more eastern Pacific energy digging into the Intermountain West and Great Basin on Thursday. This will lead to warmer and drier conditions on Wednesday and early Thursday, save for increasing chances of snowfall along and west of the Continental Divide Thursday afternoon, with moisture increasing within the increasing westerly flow. Operational models then continue to struggle with strength and location of this energy as it moves across the Rockies in the late Thursday through Saturday timeframe. Ensemble mean data from both the GEFS and EPS continue to suggest a slower and further south solution of this passing energy which would lead to good chances of mountain snowfall, as well as better chances of precipitation across the plains. Time will tell. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) Issued at 352 AM MST Sun Dec 5 2021 KCOS and KPUB... VFR conditions expected today with gusty northwest winds spreading into KCOS and KPUB by late morning with gusts to around 25-30 kts from late morning into the afternoon. A cold front will bring a northerly wind shift into both terminals in the 22z-00z time frame with the potential for gusts to around 30-40 kts possible with the frontal passage. Winds will shift around from the east during the late evening and overnight with the potential for MVFR stratus to develop over COS with low end VFR cigs possible for KPUB towards morning. KALS... Winds will remain lighter at KALS today (vs the eastern TAF sites) with winds increasing out of a northerly direction around 10- 15 kts this evening before decreasing again overnight. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 9 AM this morning to 5 PM MST this afternoon for COZ221-222-225>233. && SHORT TERM...KT LONG TERM...MW AVIATION...KT
Hazardous Weather Outlook National Weather Service Pueblo CO 515 AM MST Sun Dec 5 2021 COZ058>089-093>099-061215- Western Mosquito Range/East Lake County Above 11000 Feet- Leadville Vicinity/Lake County Below 11000 Feet- Eastern Sawatch Mountains Above 11000 Feet- Western Chaffee County Between 9000 and 11000 Feet- Central Chaffee County Below 9000 Feet- Western Mosquito Range/East Chaffee County Above 9000 Feet- Saguache County West of Continental Divide Below 10000 Feet- Saguache County East of Continental Divide Below 10000 Feet- La Garita Mountains Above 10000 Feet- Upper Rio Grande Valley/Eastern San Juan Mountains Below 10000 Feet-Eastern San Juan Mountains Above 10000 Feet- Del Norte Vicinity/Northern San Luis Valley Below 8500 Feet- Alamosa Vicinity/Central San Luis Valley Below 8500 Feet- Southern San Luis Valley- Northern Sangre de Cristo Mountains Between 8500 And 11000 Feet- Northern Sangre de Cristo Mountains Above 11000 Feet- Southern Sangre de Cristo Mountains Between 7500 and 11000 Feet- Southern Sangre de Cristo Mountains Above 11000 Feet- Northwestern Fremont County Above 8500 Feet- Western/Central Fremont County Below 8500 Feet- Wet Mountain Valley Below 8500 Feet- Wet Mountains between 6300 and 10000 Feet- Wet Mountains Above 10000 Feet- Teller County/Rampart Range Above 7500 Feet/Pikes Peak Between 7500 And 11000 Feet-Pikes Peak Above 11000 Feet- Canon City Vicinity/Eastern Fremont County- Northern El Paso County/Monument Ridge/Rampart Range Below 7500 Feet- Colorado Springs Vicinity/Southern El Paso County/Rampart Range Below 7400 Feet-Pueblo Vicinity/Pueblo County Below 6300 Feet- Walsenburg Vicinity/Upper Huerfano River Basin Below 7500 Feet- Trinidad Vicinity/Western Las Animas County Below 7500 Feet- Crowley County-La Junta Vicinity/Otero County- Eastern Las Animas County-Western Kiowa County- Eastern Kiowa County-Las Animas Vicinity/Bent County- Lamar Vicinity/Prowers County-Springfield Vicinity/Baca County- 515 AM MST Sun Dec 5 2021 This hazardous weather outlook is for portions of central...east central...south central and southeast Colorado. .DAY ONE...Today and Tonight High Fire Danger will spread across the southeast mountains and adjacent plains today as warm, dry and windy conditions spread across much of southern Colorado ahead of a storm system. West to northwest winds will gust up to 35 to 50 mph today with the strongest gusts initially over and near the mountains. A cold front will bring a sharp wind shift from the north late this afternoon and evening across the southeast plains with gusts up to 50 mph. Areas of blowing dust will be possible immediately along and behind the front which could reduce visibility to a mile or less at times. .DAYS TWO THROUGH SEVEN...Monday through Saturday Accumulating snowfall of 1 to 3 inches will be possible along the Continental Divide late Monday into Tuesday, with scattered snow and rain showers possible across the rest of the higher terrain through the eastern Plains. Another round of more impactful mountain snowfall will be possible later Thursday through Saturday, with the potential for more widespread precipitation across southeast Colorado, as a stronger weather system looks to move across the Rockies Friday and Saturday. .SPOTTER INFORMATION STATEMENT... Weather conditions that meet reporting criteria for spotters will be possible late this afternoon and evening across the southeast plains. 31/23
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Trinidad Airport reported a 58 MPH wind gust.
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, December 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: 991559.