| November 09 2024 |
Central & Southern Rockies/High Plains Major Winter Storm: (11/5/24 - 11/9/24)
By: Peter Mullinax, WPC Meteorologist
Meteorological Overview:
The Continental United States’ first major winter storm of the 2024-25 winter season was a multi-day event that produced a large footprint of heavy snow across the Central and Southern Rockies. On November 5, an upper-level trough over the Northern Rockies tracked south and strengthened over the heart of the Intermountain West. As the storm tracked south, a cold front ushered in a sufficiently cold air mass for early November that would be locked in place thanks to high pressure building in over the northwestern U.S. through mid-week. By Wednesday morning (November 6) the upper trough would become a closed 500mb low over the Four Corners region. The upper low would become cut off from the polar jet stream thanks to a strong anti-cyclonic wave break (ACWB) over the northwestern U.S.. With an anomalously cold air mass in place and a deepening upper-level low over the Four Corners region Wednesday morning, the stage was set for the impacts from this winter storm to be felt for several days.
Snow was already falling on Tuesday as the upper-level trough tracked south through the Central Rockies. It wasn’t until Tuesday night that heavy snow throughout the Colorado and New Mexico Rockies took shape as northeast winds in the wake of the cold frontal passage provided an upsloping flow component into the Front Range. In addition to this, the upper-level low track provided a prolonged period of favorable upper-level divergence atop the atmosphere. Lastly, an abundant source of 700-300mb of moisture streamed in over the region, wrapping around the closed 500mb low and leading to not only topographically-enhanced snowfall along the Front Range and Sangre De Cristo, but also a deformation zone of heavy snow that would engulf both the Central and Southern Rockies, as well as parts of the central High Plains by Thursday and Friday. Heavy snow unfolded in portions of the southern High Plains, as did blustery winds that led to whiteout conditions in parts of southeast Colorado and northeast New Mexico. The dangerous visibility reduction due to heavy snow and strong winds resulted in Blizzard Warnings being posted for northeast New Mexico on Thursday.
By Thursday night, the upper low exited Arizona and tracked east into New Mexico. The strongest upper-level divergence beneath the left-exit region of a 250mb jet streak became placed over eastern Colorado. While the Denver/Boulder metro area had seen anywhere from 2-4” of snow through mid-week, the enhanced vertical velocities aloft along with exceptional 700-300mb moisture led to periods of heavy snow in Colorado Springs, along the Palmer Divide, across the Denver metro area, and points east along Interstate 70 on Friday, November 8. The upper low would track through the Texas and Oklahoma Panhandles Friday afternoon, then northward into western Kansas Friday night where periods of moderate to heavy snow would continue in the Central Rockies and High Plains. By Saturday morning (November 9), the final periods of snow across northern Colorado and southern Wyoming would taper off throughout the day as the storm system tracked toward the Midwest.
Impacts:
This event was the first significant winter storm of the season for most of the region, but more specifically, for portions of the High Plains. Heavy snow led to numerous road closures throughout the Colorado and New Mexico Rockies. Treacherous travel conditions were observed in Albuquerque as city officials mentioned the unusually frigid temperatures and snowfall led to roughly 120 traffic crashes. Travel conditions were dangerous in Colorado with Interstate 70 being closed to traffic east of Denver through eastern Colorado. Pictures showed tractor-trailers on Interstate 70 being stranded due to icy road and whiteout conditions.
The exceptional moisture content this storm had at its disposal allowed for the snow to be a heavy/wet snow. This combined with the strong wind gusts did result in more than 50,000 customers losing power. Albuquerque’s city officials mentioned that their fire department answered over 100 calls that referenced downed trees and power lines. Hundreds of schools were closed for at least a couple of days in some of the hardest-hit areas. The one positive that came out of this early season winter storm was that it greatly benefited the ski resorts in the Southern Rockies where some resorts opened for business earlier than normal.
In terms of snowfall, the highest snowfall amount reported in WPC’s final storm summary was near Fort Garland, Colorado where an astonishing 53.3 inches of snow fell. New Mexico’s highest observed snowfall amount was 40 inches in the snow resort town of Angel Fire. The Albuquerque NWS WFO reported that Las Vegas, NM and Clayton, NM set 3-day snowfall records for November. Parts of the High Plains also witnessed impressive snowfall totals. Boise City in the Oklahoma Panhandle reported 26 inches of snow and the town of Texline in the Texas Panhandle reported 24 inches. Over five days, Denver International Airport reported 20 inches of snowfall, making this storm the biggest November winter storm in over 40 years and the city’s third-biggest November snowstorm on record.
