A winter storm packing a frosty mix of snow and ice bore down on the U.S. Northeast early on Saturday, disrupting post-holiday weekend airline traffic and prompting officials in New York and New Jersey to issue weather emergency declarations.

A family of six, including four children, suffered from possible carbon monoxide poisoning when they were using a charcoal grill to keep warm, Cy-Fair Fire Department said on Monday. The fire department said the grill may have been burning for about four ...