“There is still a lot of uncertainty in how cold we get,” the weather service said Sunday evening, but even lows in the 20s — the most likely scenario — would be “much below normal and cool enough for snow.”

Chances for lowland snow had increased slightly by Monday morning, with a 40% to 60% chance for at least 1 inch of snow between Thursday and Saturday, and a 30% chance for 2 inches or more, according to the weather service.