President-elect Donald J. Trump picked the South Dakota governor to head the Homeland Security Department, which includes the Federal Emergency Management Agency.

The affable traditional conservative from South Dakota is the first new chief of the Senate G.O.P. in nearly two decades. He will confront a challenge managing President-elect Donald J. Trump’s expectations.

The northern part of the country could see pink and red streaks in the skies this week, just in time for New Year’s Eve, according to NOAA.