The 26 January 1999 Windstorm over Southeast Colorado

On 26 January 1999 a windstorm struck portions of southeast Colorado with wind speeds estimated around 27 to 45 m/s (60 to 100 mph) for several hours. Just west of Walsenburg, Colorado, a wind gust of 44 m/s (98 mph) was reported. Damage included two over-turned trailers on interstate 25, numerous downed trees, snapped power poles and power outages.

This event cannot be simply explained as a mountain-wave induced windstorm. Walsenburg is located at least 30 km from the base of any significant mountain range and is in the center of a broad west to east river valley. The Spanish Peaks form the southern boundary of this valley and the Wet Mountains form the northern boundary.

The predominate mechanism for the strong winds is gap flows through passes in the Sangre De Cristo Mountains and down the Rio Cucharas River Valley. There are several lower passes in the Sangre de Cristo Mountain Range to the west of Walsenburg including La Veta Pass, Medano Pass and Mosca Pass. Air flowing through these passes is channeled down the Rio Cucharas River Valley into Walsenburg.

This study has three goals. First, the synoptic and mesoscale analysis of the event was conducted to aid in forecasting future windstorms in the region. Second, results of mesoscale modeling will provide insight into the processes inducing this event. Finally, this presentation will make the research community more aware of the regional flow from New Mexico up the Rio Grande Valley into the San Luis Valley, then through gaps in the Sangre De Cristo Mountains onto the plains.