After a frosty start in all but the milder central-city locations early Sunday morning, temperatures rebound quickly and top out in the upper 50s and lower 60s in the afternoon.
But then the bottom falls out as a vigorous surge of Canadian air accompanied by a few showers arrives Sunday night.
That initial push of chilly air will be followed by repeat surges of Canadian air that will periodically reinforce the chill and maintain subnormal temperatures through the rest of the seven-day forecast cycle, and possibly through the balance of October. Several weather disturbances are forecast to move across the Great Lakes region this week.
With cold air in place, that could mean the season’s first snowflakes could fall in some areas. The average date of the season’s first flakes is Oct. 30.