Snow & Wind Strand Unknown Number Of 'Off-Grid' Residents
By Chris Spears
COSTILLA COUNTY, Colo. (CBS4) - A snow emergency was declared Tuesday in Costilla County after an intense storm hit Monday night. By early Tuesday snow was reported to be falling at the rate of 2-3 inches per hour in the southern San Luis Valley.
It was the latest in a series of storms since mid-December.
As the storm moved through high winds virtually erased all previous plowing efforts on many county roads near San Luis, leaving drifts up to 10 feet deep in some areas.
Ben Doon, Chief Administrative Officer with the Costilla County Board of Commissioners, said the area has a large number of people who live off-grid.
Search and rescue efforts began early Wednesday using snowmobiles and snowcats to check on citizens and offer shelter. Doon said at least one family was being taken care of by the Red Cross and possibly a few others.
This week's storm was mainly confined to the southern part of the San Luis Valley. Only a few inches fell in nearby Alamosa.
While it's difficult to say what created such a narrow but heavy band of snow, the National Weather Service in Pueblo has a theory.
They believe the rapid rise in terrain just to the east of San Luis, combined with a powerful and moist flow in the atmosphere, could have produced a barrier jet; essentially a small scale jet stream that enhances precipitation.
A similar thing happened along the Front Range during the March 2003 blizzard.
One challenge in researching this storm will be acquiring radar data because the San Luis Valley isn't seen by area radars due to surrounding mountains.
But a research radar currently deployed as part of a local study, based at the airport in Alamosa, may have been in use at the time and could help meteorologists better understand this storm.
The San Luis Valley is a great example of how certain wind patterns in the atmosphere can interact with local terrain to produce extreme but localized weather.
Meteorologist Chris Spears writes about stories related to weather and climate in Colorado. Check out his bio, connect with him on Facebook or follow him on Twitter @ChrisCBS4.
