Environment Canada has issued a snow sqaull watch for Calgary and surrounding areas and says periods of brief but intense snowfall are expected to develop overnight.

Weather warnings were issued on Wednesday and Thursday for the mountain parks and most of central Alberta but the city was spared and only saw about two centimetres of snow.

Police say they were called to 85 crashes between 5:00 p.m. Wednesday and 5:00 a.m. Thursday. 12 of those crashes involved injuries, but none were serious.

More snow fell throughout the day as the temperatures took a downturn.

City crews were out all day clearing roads and putting down materials to prepare major routes for the additional snow that is expected to accumulate over the next few days.

A snow squall warning was issued by Environment Canada for Calgary, Airdrie, Cocrane, Olds, Sundre, Drumheller, Three Hills, Hanna, Coronation and Oyen.

The weather agency says visibility will be significantly reduced by the heavy, blowing snow and motorists may be impacted during the morning rush on Friday.

They say snow squalls cause conditions to vary quite drastically within a few kilometres and people should drive with caution.