January 11: Arctic blast in Midwest and Northeast. FAA issues ground stop at the same time North Korea launched a missile test. New details on Bob Saget’s death.

<p>Millions are waking up to dangerously low temperatures and wind chills in the Midwest and Northeast — Al Roker has everything you need to know. Plus breaking overnight: all flights on the West Coast temporarily grounded by the FAA at the same time North Korea fired off a missile test. Also, new details and the latest reaction on Bob Saget’s sudden death — Savannah Guthrie speaks with his close friend and touring partner Mike Young.</p>