Number of Frost Free Days

149*

* Average number of days between the last frost and first frost/ based on the 1951 - 80 period of record.

Prevailing Winds:

South/Southwest

Unusual Weather Conditions:

The role of Lake Huron and Georgian Bay in modifying temperatures of the surrounding shores is one of their most fundamental effects on the climate of Collingwood.  The "Lake Effect" generally causes cooler temperatures to occur along the shores of the lake during summer and milder temperatures in winter.  The overall moderating effect is that of a generally longer growing season (more frost-free days) than is found at similar latitudes.

Another key aspect of "Lake Effect" weather is the amount and type of snowfall experienced in areas to the lee of the lakes during the winter months.  Brief, blinding snow squalls are punctuated intermittently by periods of brilliant sunshine.  The snow fall extends only 30-40 km inland.  Areas close to the lakes, such as Collingwood, may experience heavy snowfalls, but inland areas seem to escape the brunt of these storms.