GFS forecast lows across the Lower 48 for Monday night
Canadian high pressure dives southward the next 48 hours
I'm projecting overnight low temperatures to plummet to the teens across the Mid-South (see first attached image). By daybreak on Tuesday, Nashville will dip to 16°. That forecast is a couple degrees colder than it was all of last winter, and the coldest air we've seen since February 2011.
This arctic outbreak is really flexing its muscle along the Canada-U.S. border. Temperatures this morning at 6:00 a.m. were -26° Fahrenheit in Warroad, Minnesota, which is northwest of International Falls (often the coldest spot in the Lower 48). Highs today in that region will be in the teens below zero. After 50 mph winds and blowing snow caused blizzard conditions this past weekend, the arctic chill just adds insult to injury. As someone who spent one winter in Sioux Falls, South Dakota (my first television job out of college) I can tell you that not too many people will venture outside in weather like this.
Lows tonight in parts of the Upper Midwest will be dangerously cold, possibly as low as -32° Fahrenheit near the Canadian border (see second attached image).
After highs on Tuesday fail to reach the freezing mark across the Mid-South, readings will fall back to the teens Tuesday night into Wednesday morning. We have cold, Canadian high pressure to blame for the arctic snap, which you can see in the third attached image.
Please consider bringing any outdoor pets indoors, and at the very least provide them with extra straw, blankets, etc. A friendly reminder that you may want to drip your faucets and of course disconnect your hose from the spigot outdoors.