After breaking a new high temperature record Saturday at 24C, Calgary is expecting a run of daytime highs that will keep it below freezing for at least a week.
A change in the weather pattern early in the week will bring in colder Arctic air and the possibility of snow.
The Halloween forecast is expected to be seasonal with a high of 8C and an overnight low of -3C with a chance of rain. But once the mercury drops below 0C Tuesday night, the cold will stay for a while.
Forecast daytime highs after Wednesday are in the -1C to -10C range with overnight temperatures between -7C to -17C.
The average temperatures in Calgary this time of year are between 9C and -4C, meaning by the end of the week Calgary will be almost 20C below normal.
Snow is likely Wednesday to Saturday with anywhere between 10 to 30 centimetres possible. Typically, the month of November will see a total of 17 centimeters of snow.
The last time Calgary saw a stretch of days below 0 C was March 2017.
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