Environmental and financial considerations dictate that chemical usage in winter highway maintenance operations must be accomplished in the most efficient manner possible. The objective of this study was to develop correlations between meteorologic parameters and chemical effectiveness to better understand the optimum conditions for which a particular chemical application is most effective. This information is of practical benefit when used in conjunction with predictive meteorologic information. The emphasis on the chemical treatment was anti-icing, since chemicals are more efficiently utilized for adhesion prevention than for removing ice or compacted snow already in place. Although the major emphasis of this study was to assess the anti-icing properties of each chemical for different scenarios, some tests included deicing to some extent, out of necessity.