The first major winter storm of the season will strike parts of Southwestern and north-central United States between Monday and Wednesday, causing widespread power outages and making travel nearly impossible, forecasters said...Dangerous Arctic air could spill southward by midweek. The Midwest and northern Plains will experience wind chills of 30 to 40 degrees below zero...Many temperatures will be below zero Thursday morning, and daytime highs will struggle to make it out of the single digits across the Upper Great Lakes, according to forecasters.