The design ground snow loads at specific stations around the state of Montana are available in the snow loads tables in the downloadable copy of the snow loads report highlighted at the bottom of this page. The tool below provides ground snow load values for any latitude and longitude in the state of Montana, and it is intended to be used to find snow loads at points away from a station and/or at a different elevation from a station.  This value is the result of an interpolation of station values (normalized to elevation) that is multiplied by the actual elevation at the location of interest. This tool is the preferred method for finding ground snow loads, relative to the snow load contour maps contained in the report below.  The Snow Load Finder also provides snow load and elevation information from the three closest stations surrounding the point of interest, so that the engineer can get a sense of the local variation of the snow loads in the area of interest.  The methodology used to develop this tool, values of ground snow loads for sampled sites, and example solved problems are contained in the document downloadable at the bottom of this page. It is very important that the user of this Snow Load Finder Tool understand how to properly interpret the results it provides and use good engineering judgement in their implementation. It is important to remember that elevation is a critical parameter in determining ground snow loads in Montana (snow loads increase with elevation).

Upon determining the ground snow load for a specific location, it is recommended that the design engineer check with local building officials (in the area of the structure) for minimum ground or roof snow load values to be used for design of structures in that location. Consideration should also be given to any conditions that might influence snow accumulation at the specific site of interest relative to the `average' maximum ground snow load reported for the area by this tool.

Local and/or state requirements on the ground snow loads or the roof loads subsequently calculated from these values supercede the values provided by this Snow Load Finder Tool. Note that the State of Montana requires a minimum roof snow load of 30 psf be used for design.

Montana Ground Snow Load Finder

44.25 to 48.95 Degrees
104.00 to 116.10 Degrees
Ground snow load is highly sensitive to geographic location (elevation). It is recommended that latitude and longitude be input with the greatest precision possible, preferably to the nearest 0.001 degree (about 120 yards)

This revision to the manual "Snowloads for Structural Design in Montana (Revised, 2004)" was made possible by the support of the Civil Engineering Department at Montana State University and the Montana Section of the American Society of Civil Engineers.  Please send contributions to offset the cost of this effort to:
                      Snow Loads Guide
                      c/o Civil Engineering Dept.
                      205 Cobleigh Hall - MSU
                      Bozeman, MT 59717 - 3900

Please make checks payable to Montana State University (suggested amount: $50.00).

Snow Loads for Structural Design
MT Snowloads with Maps (pdf file) (54 Mb file)
MT Snowloads without Maps (pdf file) (4 Mb file)
Corrected Snow Load Map 5 (pdf file) (2 Mb file)
Technical questions about the application can be directed to:
Jerry Stephens