The phrase "adjacent traffic" is correct and usable in written English.
You can use it to refer to traffic that is in close proximity to each other, typically on different lanes of a freeway. For example, "The driver had to be extra cautious of the adjacent traffic on the highway."
Piles of dried leaves were mixed with candy wrappers, soda cans, beer bottles, coffee cups and yellowed newspapers, enclosed like a giant wastebasket by a 10-foot-high chain link fence surrounding the courthouse and an adjacent traffic island.
Yet, in October, construction will be completed on a fifty-four-inch-high steel barrier between the walkway and the adjacent traffic lanes which is meant to prevent bicyclists from veering into traffic.
En route, the A7 executed lane changes, modulating its speed to match the pace of adjacent traffic.
At speeds above 35 mph, Active Warning Railroad systems are used in conjunction with adjacent traffic signal controls [21].
In a HetNet, users generally experience a large variety of interference levels depending on their associations, locations, and adjacent traffic loads for the uplinks.
This same study, which included an older adult age group, found that when using the BSW system, participants adjusted their lane position slightly away from vehicles in the blind spot, indicating that the BSW increased driver awareness of adjacent traffic.
I had to get changed in the car, which I hope made the bus-driver's day as we sat adjacent in traffic.
However, conventional field measurements for these analyses present safety concerns because they require personnel to be in or adjacent to traffic lanes.
Both processes are described by many existing models and experiments, on-site and in wind tunnels, focussing e.g. on urban street canyons and crossings or vegetation barriers adjacent to traffic sources.
However, the only transgression on a diagonal out of a station line was observed at the same LC, which could be associated with an impatience to wait at the adjacent road traffic lights.
The freeway gridlock also helped snarl adjacent freeway traffic.
