AIR MAIL
Where today’s air came from
The air arriving over Mullica about 5,000 feet above the ground was over the Atlantic off the Carolinas three days ago, and over Ontario a day ago, about 1,410 miles back along its path. The nine paths traced from around the city fan out, so treat that as a best guess. Near the ground the air came from Quebec; at 10,000 feet, from the Mid-Atlantic. Traced back 72 hours through NOAA’s hourly RAP analyses and the GFS beyond them, nine paths at each of three heights.