Winter Storm — Southern San Luis Valley, Colorado

2003-03-17 to 2003-03-20 · Southern San Luis Valley, Colorado

Wider weather episode

A large, slow moving, moist system set up over the southern Great Plains on the 17th and brought persistent rain and snow to southern Colorado from the evening of the 17th to the morning of the 20th. Most of the accumulating snow fell above 6000 feet, which included the central and southeast mountains and high valleys...as well as the adjacent plains. Areas hardest hit by snow on the plains were the northern half of El Paso county and from southern Pueblo county to the New Mexico state line. Snow amounts just north of Colorado Springs reached above 3 feet, while the official reading at the airport was just 1.7 inches. Many areas around Trinidad in Las Animas county received over 1 foot of snow with Huerfano county snow amounts close to the mountains ranging from 1 1/2 feet to nearly 4 feet. In addition, sustained winds of 20 to 40 mph caused considerable blowing and drifting of snow, and blizzard conditions at times, closing several highways and portions of Interstate 25. Snow drifts of 4 to 10 feet were common across portions of northern El Paso county, north of Colorado Springs.Heavy snow accumulations pushed over the Sangre de Cristo mountains into the San Luis Valley and into the Upper Arkansas River Valley in Chaffee and Lake counties. Snow amounts topped two feet in many locations in those areas.The greatest snow amounts occurred in or near the appropriately named "Wet Mountains" in Pueblo and Custer counties. Unstable, moist air flowed into the Wet Mountains through the period allowing large amounts of snow to fall. Snow amounts were around 5 feet in Custer county northeast of Westcliffe. However, even higher snow amounts were measured and estimated on the east slopes of the Wet Mountains...on the Pueblo/Custer county line between 8700 and 9000 feet. Just north of San Isabel Lake in Custer county on highway 165, a very accurate measurement of 74 inches of snow was made. In that same area, an estimate of around 84 inches was reported on the shore of San Isabel Lake. Similar estimates of 6 feet were confirmed a few miles north of San Isabel Lake. Many of the SNOTEL sites high in the southeast mountains reported between 2 and 4 feet of new snow with this storm, which equated to an increase of snow water equivalent (SWE) of anywhere from 1 to almost 5 inches.

Source: NOAA Storm Events Database, event_id 5346400. Narrative written by the NWS forecast office that issued the report.