AIR MAIL
Where today’s air came from
The air arriving over Grove Park-Tilden about 5,000 feet above the ground was over southern California three days ago, and over the northern Rockies a day ago, about 1,620 miles back along its path. Most of the nine paths traced from around the city agree. Near the ground the air came from the Mississippi Valley; at 10,000 feet, from the Pacific off California. It feels humid. Traced back 72 hours through NOAA’s hourly RAP analyses, nine paths at each of three heights.