AIR MAIL
Where today’s air came from
The air arriving over Wentworth about 5,000 feet above the ground was over the North Atlantic three days ago, and over the western Atlantic a day ago, about 1,270 miles back along its path. It rose from near the ground on the way. Near the ground the air came from a point about 630 miles to the northeast; at 10,000 feet, from the western Atlantic. Traced back 72 hours through NOAA’s hourly RAP analyses and the GFS beyond them, nine paths at each of three heights.