Does an August Singularity Exist in the Northern Rockies of the United States?

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Peter T. Soule' Ph.D., Professor (Creator)
Appalachian State University (ASU )
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Abstract: Climatic singularities offer a degree of orderliness to notable meteorological events that are typically characterized by significant temporal variability. Significant deviations from normal daily maximum temperatures that occur following the passage of a strong mid-latitude cyclone in mid- to late August in the northern Rocky Mountains of the United States are recognized in the local culture as the “August Singularity.” Daily standardized maximum temperature anomalies for August–October were examined for eight climate stations in Montana and Idaho as indicators of major mid-latitude storms. The data indicate that a single-day negative maximum temperature singularity exists for 13 August. Further, a 3-day singularity event exists for 24–26 August. It is concluded that the concept of an August Singularity in the northern Rockies is valid, because the high frequency of recorded negative maximum temperature anomalies suggests that there are specific time intervals during late summer that are more likely to experience a major mid-latitude storm. The principal benefit to society for the August Singularity is that the reduced temperatures help in the efforts to control wildfires that are common this time of year in the northern Rockies.

Additional Information

Peter T. Soulé & Paul A. Knapp "Does an August Singularity Exist in the Northern Rockies of the United States?" Journal of Applied Meteorology and Climatology (open access journal) Volume 47 pp.1845-1850 Version of Record Available from (
Language: English
Date: 2008
summer, warm season, annual variations, temperature, mountain meteorology, seasonal effects

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