REPLY TO COMMENTS ON "HEAVY SNOWFALL DURING AN ARCTIC: OUTBREAK ALONG THE COLORADO FRONT RANGE"

• Main Authors: Doug Wesley, John Weaver, Roger Pielke
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1991
• Subjects: Arctic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.489.6879; http://pielkeclimatesci.files.wordpress.com/2009/09/r-170.pdf

be as unusual a weather situation as Dr. Auer implies in his first paragraph. It is a common occurrence along the Front Range for surface pressure to increase rapidly as snowfall increases in intensity. Much of the discussion in the second paragraph of Dr. Auer's note seems to agree with the major pointsiof WWP. One important point: most of the average terrain height along the Continental Divide in northern Colorado and southern Wyoming ranges from 7<XX> to I(xxx) ft MSL. In the case of the February 1989 storm, the deepening of the cold air to and above IO,<XX> ft was followed by propagation of the cold air westward, over the Divide and down the western slope of Colorado. In fact, this 'spillover ' induced extremely heavy snowfall in those regions. We feel that westward propagation in this type of storm is inevitable if the cold air deepens to a height greater than the average barrier height, given the We thank Dr. Auer for his interesting comments (Auer, 1991) on our manuscript (Wesley et al., 1990, hereafter refer-enced as WWP). The components of his note are particularly useful due to his extensive experience in observing snow-storms for many years in this region. Certainly, the extreme arctic outbreaks of the type which occurred 1-5 February 1989 may occur only about once or twice per decade in this region, and our experience supports this qualitative estimate. However, less extreme but dynami-cally similar events, such as 9-10 February 1988 (Wesley and