pokemon-go
I've seen several yellow stripes on the Pokemon Go map around my city. They look as if they are a road or a trail of some kind they are always straight. They never correspond to anything on the ground, nor anything on Google maps.
In this example the stripe goes literally into nowhere.
The different colours you see are different "environments". To quote the Pokemon GO FAQ:
Some wild Pokémon appear only in certain environments and climates. For example, some Pokémon may appear only near lakes, oceans, or other bodies of water
"Environments" are based off GPS maps, and are somewhat accurate to the real world. You should expect to see water where there should be a lake, and grass where there should be grass. Buildings appear to always show up as grass. Also consider that it will not be 100% accurate; in the screenshot, above, the 'water' is actually a children's playground.
As a side note, if you stay in the same area for a while, the ground appears to slowly turn grey and patchy. From my observations, these are 'dry areas'. They show up if you are in the area for a long time, and Pokemon generally do not spawn when you are standing on them.
My data isn't complete as I haven't been actively keeping track, but here is what Iv'e found. Once you reach max CP for any Pokemon at your level, every subsequent level allows you to power up said Pokemon twice. Each power up grants 20-60(level 4-16) CP based off of the Pokemon's initial power and player level. My Lapras maxed out at 971 at level 11, 1056 at level 12, ~1140 (forgot screenshot) at level 13 and 1267 at level 14. +85, +~90, +~120. I have since run out of Lapras candies so i can't pursue this information further until i obtain more. I'll attempt to gather more data using a more common Pokemon later (Eevee evolution probably) and edit when i can, but the stardust needed is hard to maintain.
How this relates to the question:
The encounter CP is a random number between lowest possible (10 in 1st evolution) and maximum possible. From the data we can see that the max CP does increase incrementally so as a result encounter CP will increase at the same rate.
In conclusion, while it is more effective to power up and evolve Pokemon later, the max CP increase seems to be mild enough that from level to level the difference isn't insurmountable.
Best Answer
After having looked through a few threads, it seems to be happening in many places. And as such it's probably due to an error with the map itself.
In this situation, the road seems to "collide" with itself.